INN monograph
Voriconazole
Azole Antifungal [EPC] · POM
Verified · Updated 01 Aug 2026 · Source: Local active-ingredient clinical extract; FDA drug label via OpenFDA/DailyMed; Professional class pharmacology (Antifungal)
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Contraindications
- 4 CONTRAINDICATIONS • VFEND is contraindicated in patients with known hypersensitivity to voriconazole or its excipients [see Warnings and Precautions (5.5) and Adverse Reactions (6.1, 6.2) ] .
- There is no information regarding cross-sensitivity between VFEND and other azole antifungal agents.
- Refer to the prescribing information for other azole antifungal agents. • Concomittant use of VFEND with the interacting drugs described and listed below in this section are a guide and not considered a comprehensive list of all possible drugs that may be contraindicated with VFEND. 1.
- Concomitant use of VFEND is contraindicated with drugs that are highly dependent on CYP3A4 for metabolism, and for which elevated plasma concentrations are associated with serious and/or life‑threatening reactions [see Drug Interactions (7) ]: • Eplerenone • Ergot alkaloids (e.g., ergotamine, dihydroergotamine) • Finerenone • Ivabradine • Lurasidone • Naloxegol • Pimozide • Quinidine • Rifabutin [see Clinical Pharmacology (12.3) ] • Sirolimus [see Clinical Pharmacology (12.3) ] • Tolvaptan • Venetoclax: Coadministration at initiation and during the ramp-up phase is contraindicated in patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) due to the potential for increased risk of tumor lysis syndrome [see Drug Interactions (7) ] . • Voclosporin 2.
- Concomitant use of VFEND is contraindicated with drugs and herbal products that induce CYP2C19, CYP2C9, and/or CYP3A4 and for which significantly reduced voriconazole plasma concentrations may be associated with loss of efficacy [see Drug Interactions (7) ]: • Carbamazepine • Efavirenz Concomitant use with efavirenz dosages of 400 mg every 24 hours or higher is contraindicated [see Clinical Pharmacology (12.3) ] . • Long-acting barbiturates • Rifabutin • Rifampin • Ritonavir Concomitant use with high-dose ritonavir (400 mg every 12 hours) is contraindicated.
- Concomitant use with low-dose ritonavir (100 mg every 12 hours) should be avoided, unless an assessment of the benefit/risk to the patient justifies the use of VFEND [see Clinical Pharmacology (12.3) ] . • St.
- John’s Wort [see Clinical Pharmacology (12.3) ] • Known hypersensitivity to voriconazole or its excipients ( 4 ) • Concomitant use with drugs that are highly dependent on CYP3A4 for metabolism, and for which elevated plasma concentrations are associated with serious and/or life-threatening reactions ( 4 , 7 ) • Concomitant use with drugs and herbal products that induce CYP2C19, CYP2C9, and/or CYP3A4 and for which significantly reduced voriconazole plasma concentrations may be associated with loss of efficacy ( 4 , 7 )
Precautions
- 5 WARNINGS AND PRECAUTIONS • Hepatic Toxicity : Serious hepatic reactions reported.
- Evaluate liver function tests at start of and during VFEND therapy ( 5.1 ) • Arrhythmias and QT Prolongation : Correct potassium, magnesium, and calcium prior to use
- caution patients with proarrhythmic conditions ( 5.2 ) • Infusion Related Reactions (including anaphylaxis) : Stop the infusion ( 5.3 ) • Visual Disturbances (including optic neuritis and papilledema): Monitor visual function if treatment continues beyond 28 days ( 5.4 ) • Severe Cutaneous Adverse Reactions : Discontinue for exfoliative cutaneous reactions ( 5.5 ) • Photosensitivity : Avoid sunlight due to risk of photosensitivity ( 5.6 ) • Adrenal Dysfunction : Carefully monitor patients receiving VFEND and corticosteroids (via all routes of administration) for adrenal dysfunction both during and after VFEND treatment.
- Instruct patients to seek immediate medical care if they develop signs and symptoms of Cushing's syndrome or adrenal insufficiency ( 5.8 ) • Embryo-Fetal Toxicity : Voriconazole can cause fetal harm when administered to a pregnant woman.
- Inform pregnant patients of the potential hazard to the fetus.
- Advise females of reproductive potential to use effective contraception during treatment with VFEND ( 5.9 , 8.1 , 8.3 ) • Skeletal Adverse Reactions : Fluorosis and periostitis with long-term voriconazole therapy.
- Discontinue if these adverse reactions occur ( 5.12 ) • Clinically Significant Drug Interactions : Review patient's concomitant medications ( 5.13 , 7 ) 5.1 Hepatic Toxicity In clinical trials, there have been uncommon cases of serious hepatic reactions during treatment with VFEND (including clinical hepatitis, cholestasis and fulminant hepatic failure, including fatalities).
- Instances of hepatic reactions were noted to occur primarily in patients with serious underlying medical conditions (predominantly hematological malignancy).
- Hepatic reactions, including hepatitis and jaundice, have occurred among patients with no other identifiable risk factors.
- Liver dysfunction has usually been reversible on discontinuation of therapy [see Adverse Reactions (6.1) ] .
- A higher frequency of liver enzyme elevations was observed in the pediatric population [see Adverse Reactions (6.1) ] .
- Hepatic function should be monitored in both adult and pediatric patients.
Point of care
Dosing
Adult
• Dosage in Adults ( 2.3 ) Infection Loading Dose Maintenance Dose Intravenous infusion Intravenous infusion Oral tablets Oral suspension Invasive Aspergillosis 6 mg/kg every 12 hours for the first 24 hours 4 mg/kg every 12 hours 200 mg every 12 hours 5 mL every 12 hours Candidemia in nonneutropenics and other deep tissue Candida infections 3–4 mg/kg every 12 hours 200 mg every 12 hours 5 mL every 12 hours Scedosporiosis and Fusariosis 4 mg/kg every 12 hours 200 mg every 12 hours 5 mL every 12 hours Esophageal Candidiasis Not Evaluated Not Evaluated 200 mg every 12 hours 5 mL every 12 hours o Adult patients weighing less than 40 kg: oral maintenance dose 100 mg or 150 mg every 12 hours o Hepatic Impairment : Use half the maintenance dose in adult patients with mild to moderate hepatic impairment (Child-Pugh Class A and B) ( 2.5 ) o Renal Impairment : Avoid intravenous administration in adult patients with moderate to severe renal impairment (creatinine clearance <50 mL/min) ( 2.6 ) • Dosage in Pediatric Patients 2 years of age and older ( 2.4 ) o For pediatric patients 2 to less than 12 years of age and 12 to 14 years of age weighing less than 50 kg see Table below. Infection Loading Dose Maintenance Dose Intravenous infusion Intravenous infusion Oral tablets Oral suspension Invasive Aspergillosis 9 mg/kg every 12 hours for the first 24 hours 8 mg/kg every 12 hours after the first 24 hours 9 mg/kg every 12 hours (maximum dose of 350 mg every 12 hours) 0.225 mL/kg every 12 hours [maximum dose of 8.75 mL (350 mg) every 12 hours] Candidemia in nonneutropenics and other deep tissue Candida infections Scedosporiosis and Fusariosis Esophageal Candidiasis Not Evaluated 4 mg/kg every 12 hours 9 mg/kg every 12 hours (maximum dose of 350 mg every 12 hours) 0.225 mL/kg every 12 hours [maximum dose of 8.75 mL (350 mg) every 12 hours] o For pediatric patients aged 12 to 14 years weighing greater than or equal to 50 kg and those aged 15 years and older regardless of body weight use adult dosage. ( 2.4 ) o Dosage adjustment of VFEND in pediatric patients with renal or hepatic impairment has not been established ( 2.5 , 2.6 ) • See full prescribing information for instructions on reconstitution of VFEND lyophilized powder for intravenous use and important administration instructions ( 2.1 , 2.6 , 2.7 ) 2.1 Important Administration Instructions for Use in All Patients VFEND I.V. for Injection requires reconstitution to 10 mg/mL and subsequent dilution to 5 mg/mL or less prior to administration as an infusion, at a maximum rate of 3 mg/kg per hour over 1 to 3 hours. Administer diluted VFEND I.V. by intravenous infusion over 1 to 3 hours only. Do not administer as an IV bolus injection. 2.2 Use of VFEND I.V. with Other Parenteral Drug Products Blood products and concentrated electrolytes VFEND I.V. must not be infused concomitantly with any blood product or short-term infusion of concentrated electrolytes, even if the two infusions are running in separate intravenous lines (or cannulas). Electrolyte disturbances such as hypokalemia, hypomagnesemia and hypocalcemia should be corrected prior to initiation of and during VFEND therapy [see Warnings and Precautions (5.10) ] . Intravenous solutions containing (non-concentrated) electrolytes VFEND I.V. can be infused at the same time as other intravenous solutions containing (non-concentrated) electrolytes, but must be infused through a separate line. Total parenteral nutrition (TPN) VFEND I.V. can be infused at the same time as total parenteral nutrition, but must be infused in a separate line. If infused through a multiple-lumen catheter, TPN needs to be administered using a different port from the one used for VFEND I.V. 2.3 Recommended Dosing Regimen in Adults Invasive aspergillosis and serious fungal infections due to Fusarium spp. and Scedosporium apiospermum See Table 1. Therapy must be initiated with the specified loading dose regimen of intravenous VFEND on Day 1 followed by the recommended maintenance dose (RMD) regimen. Intravenous treatment should be continued for at least 7 days. Once the patient has clinically improved and can tolerate medication given by mouth, the oral tablet form or oral suspension form of VFEND may be utilized. The recommended oral maintenance dose of 200 mg achieves a voriconazole exposure similar to 3 mg/kg intravenously; a 300 mg oral dose achieves an exposure similar to 4 mg/kg intravenously [see Clinical Pharmacology (12.3) ] . Candidemia in non-neutropenic patients and other deep tissue Candida infections See Table 1. Patients should be treated for at least 14 days following resolution of symptoms or following last positive culture, whichever is longer. Esophageal Candidiasis See Table 1. Patients should be treated for a minimum of 14 days and for at least 7 days following resolution of symptoms. Table 1: Recommended Dosing Regimen (Adults) Infection Loading Dose Maintenance Dose Increase dose when VFEND is coadministered with phenytoin or efavirenz (7); Decrease dose in patients with hepatic impairment (2.5) , In healthy volunteer studies, the 200 mg oral every 12 hours dose provided an exposure (AUC τ ) similar to a 3 mg/kg intravenous infusion every 12 hours dose; the 300 mg oral every 12 hours dose provided an exposure (AUC τ ) similar to a 4 mg/kg intravenous infusion every 12 hours dose (12) . Intravenous infusion Intravenous infusion Oral tablets Adult patients who weigh less than 40 kg should receive half of the oral maintenance dose. Oral suspension Invasive Aspergillosis In a clinical study of IA, the median duration of intravenous VFEND therapy was 10 days (range 2 to 85 days). The median duration of oral VFEND therapy was 76 days (range 2 to 232 days) (14.1) . 6 mg/kg every 12 hours for the first 24 hours 4 mg/kg every 12 hours 200 mg every 12 hours 5 mL every 12 hours Candidemia in nonneutropenic patients and other deep tissue Candida infections 6 mg/kg every 12 hours for the first 24 hours 3–4 mg/kg every 12 hours In clinical trials, patients with candidemia received 3 mg/kg intravenous infusion every 12 hours as primary therapy, while patients with other deep tissue Candida infections received 4 mg/kg every 12 hours as salvage therapy. Appropriate dose should be based on the severity and nature of the infection. 200 mg every 12 hours 5 mL every 12 hours Esophageal Candidiasis Not Evaluated Not evaluated in patients with EC. Not Evaluated 200 mg every 12 hours 5 mL every 12 hours Scedosporiosis and Fusariosis 6 mg/kg every 12 hours for the first 24 hours 4 mg/kg every 12 hours 200 mg every 12 hours 5 mL every 12 hours Method for Adjusting the Dosing Regimen in Adults • If the patient's response is inadequate, the oral maintenance dose for VFEND tablets or oral suspension may be increased from 200 mg (or 5 mL) every 12 hours to 300 mg (or 7.5 mL) every 12 hours. • For adult patients weighing less than 40 kg, the oral maintenance dose for VFEND tablets or oral suspension may be increased from 100 mg (or 2.5 mL) every 12 hours to 150 mg (or 3.75 mL) every 12 hours. • If the patient is unable to tolerate 300 mg (or 7.5 mL) orally every 12 hours, reduce the oral maintenance dose of VFEND tablets or oral suspension by 50 mg (or 1.25 mL) steps to a minimum of 200 mg (or 5 mL) every 12 hours for adult patients weighing more than 40 kg or to 100 mg (or 2.5 mL) every 12 hours for adult patients weighing less than 40 kg. • If the patient is unable to tolerate 4 mg/kg intravenously every 12 hours, reduce the intravenous maintenance dose to 3 mg/kg every 12 hours. 2.4 Recommended Dosing Regimen in Pediatric Patients The recommended dosing regimen for pediatric patients 2 to less than 12 years of age and 12 to 14 years of age with body weight less than 50 kg is shown in Table 2. For pediatric patients 12 to 14 years of age with a body weight greater than or equal to 50 kg and those 15 years of age and above regardless of body weight, administer the adult dosing regimen of VFEND [see Dosage and Administration (2.3) ] . Table 2: Recommended Dosing Regimen for Pediatric Patients 2 to less than 12 years of age and 12 to 14 years of age with body weight less than 50 kg Based on a population pharmacokinetic analysis in 112 immunocompromised pediatric patients aged 2 to less than 12 years of age and 26 immunocompromised pediatric patients aged 12 to less than 17 years of age. Loading Dose Maintenance Dose Intravenous infusion Intravenous infusion Oral tablets Oral suspension Invasive Aspergillosis In the Phase 3 clinical trials, patients with IA received intravenous (IV) treatment for at least 6 weeks and up to a maximum of 12 weeks. Patients received IV treatment for at least the first 7 days of therapy and then could be switched to oral VFEND therapy. 9 mg/kg every 12 hours for the first 24 hours 8 mg/kg every 12 hours after the first 24 hours 9 mg/kg every 12 hours (maximum dose of 350 mg every 12 hours) 0.225 mL/kg every 12 hours [maximum dose of 8.75 mL (350 mg) every 12 hours] Candidemia in nonneutropenics and other deep tissue Candida infections Study treatment for primary or salvage invasive candidiasis and candidemia (ICC) or EC consisted of intravenous VFEND, with an option to switch to oral therapy after at least 5 days of IV therapy, based on subjects meeting switch criteria. For subjects with primary or salvage ICC, VFEND was administered for at least 14 days after the last positive culture. A maximum of 42 days of treatment was permitted. Patients with primary or salvage EC were treated for at least 7 days after the resolution of clinical signs and symptoms. A maximum of 42 days of treatment was permitted. Scedosporiosis and Fusariosis Esophageal Candidiasis Not Evaluated 4 mg/kg every 12 hours 9 mg/kg every 12 hours (maximum dose of 350 mg every 12 hours) 0.225 mL/kg every 12 hours [maximum dose of 8.75 mL (350 mg) every 12 hours] Initiate therapy with an intravenous infusion regimen. Consider an oral regimen only after there is a significant clinical improvement. Note that an 8 mg/kg intravenous dose will provide voriconazole exposure approximately 2-fold higher than a 9 mg/kg oral dose. Oral bioavailability may be limited in pediatric patients 2 to 12 years with malabsorption and very low body weight for age. In that case, intravenous VFEND administration is recommended. Method for Adjusting the Dosing Regimen in Pediatric Patients Pediatric Patients 2 to less than 12 years of age and 12 to 14 years of age with body weight less than 50 kg If patient response is inadequate and the patient is able to tolerate the initial intravenous maintenance dose, the maintenance dose may be increased by 1 mg/kg steps. If patient response is inadequate and the patient is able to tolerate the oral maintenance dose, the dose may be increased by 1 mg/kg (0.025 mL/kg) steps or 50 mg (1.25 mL) steps to a maximum of 350 mg (8.75 mL) every 12 hours. If patients are unable to tolerate the initial intravenous maintenance dose, reduce the dose by 1 mg/kg steps. If patients are unable to tolerate the oral maintenance dose, reduce the dose by 1 mg/kg (0.025 mL/kg) or 50 mg (1.25 mL) steps. Pediatric patients 12 to 14 years of age weighing greater than or equal to 50 kg and 15 years of age and older regardless of body weight: Use the optimal method for titrating dosage recommended for adults [see Dosage and Administration (2.3) ] . 2.5 Dosage Modifications in Patients With Hepatic Impairment Adults The maintenance dose of VFEND should be reduced in adult patients with mild to moderate hepatic impairment, Child-Pugh Class A and B. There are no PK data to allow for dosage adjustment recommendations in patients with severe hepatic impairment (Child-Pugh Class C). Duration of therapy should be based on the severity of the patient's underlying disease, recovery from immunosuppression, and clinical response. Adult patients with baseline liver function tests (ALT, AST) of up to 5 times the upper limit of…
Paediatric
8.4 Pediatric Use The safety and effectiveness of VFEND have been established in pediatric patients 2 years of age and older based on evidence from adequate and well-controlled studies in adult and pediatric patients and additional pediatric pharmacokinetic and safety data. A total of 105 pediatric patients aged 2 to less than 12 [N=26] and aged 12 to less than 18 [N=79] from two, non-comparative Phase 3 pediatric studies and eight adult therapeutic trials provided safety information for VFEND use in the pediatric population [see Adverse Reactions (6.1) , Clinical Pharmacology (12.3) , and Clinical Studies (14) ] . Safety and effectiveness in pediatric patients below the age of 2 years has not been established. Therefore, VFEND is not recommended for pediatric patients less than 2 years of age. A higher frequency of liver enzyme elevations was observed in the pediatric patients [see Dosage and Administration (2.5) , Warnings and Precautions (5.1) , and Adverse Reactions (6.1) ] . The frequency of phototoxicity reactions is higher in the pediatric population. Squamous cell carcinoma has been reported in patients who experience photosensitivity reactions. Stringent measures for photoprotection are warranted. Sun avoidance and dermatologic follow-up are recommended in pediatric patients experiencing photoaging injuries, such as lentigines or ephelides, even after treatment discontinuation [see Warnings and Precautions (5.6) ]. VFEND has not been studied in pediatric patients with hepatic or renal impairment [see Dosage and Administration (2.5 , 2.6) ] . Hepatic function and serum creatinine levels should be closely monitored in pediatric patients [see Dosage and Administration (2.6) and Warnings and Precautions (5.1 , 5.10) ] .
Renal
Fluconazole dose-adjust in CKD; amphotericin nephrotoxicity high-alert.
- CrCl 0–120: Confirm renal dosing in product SmPC / primary label.
Hepatic
Monitor LFTs for courses >14 days or higher-risk patients.
Safety
Drug interactions
- Match agent to site and species.
- For tinea, continue topical beyond clearance.
- Invasive fungal disease needs ID/specialist input and source control.
Safety
Adverse effects
- labeling: Hepatic Toxicity [see Warnings and Precautions (5.1) ] Arrhythmias and QT Prolongation [see Warnings and Precautions (5.2) ] Infusion Related Reactions [see Warnings and Precautions (5.3) ] Visual Disturbances [see Warnings and Precautions (5.4) ] Severe Cutaneous Adverse Reactions [see Warnings and Precautions (5.5) ] Photosensitivity [see Warnings and Precautions (5.6) ] Renal Toxicity [see Warnings and Precautions (5.7) ] • Adult Patients : The most common adverse reactions (incidence ≥2%) were visual disturbances, fever, nausea, rash, vomiting, chills, headache, liver function test abnormal, tachycardia, hallucinations ( 6 ) • Pediatric Patients : The most common adverse reactions (incidence ≥5%) were visual disturbances, pyrexia, vomiting, epistaxis, nausea, rash, abdominal pain, diarrhea, hypertension, hypokalemia, cough, headache, thrombocytopenia, ALT abnormal, hypotension, peripheral edema, hyperglycemia, tachycardia, dyspnea, hypocalcemia, hypophosphatemia, LFT abnormal, mucosal inflammation, photophobia, abdominal distention, constipation, dizziness, hallucinations, hemoptysis, hypoalbuminemia, hypomagnesemia, renal impairment, upper respiratory tract infection ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
- Clinical Trials Experience in Adults Overview The most frequently reported adverse reactions (see Table 4 ) in the adult therapeutic trials were visual disturbances (18.7%), fever (5.7%), nausea (5.4%), rash (5.3%), vomiting (4.4%), chills (3.7%), headache (3.0%), liver function test increased (2.7%), tachycardia (2.4%), hallucinations (2.4%).
- The adverse reactions which most often led to discontinuation of voriconazole therapy were elevated liver function tests, rash, and visual disturbances [see Warning and Precautions (5.1 , 5.4) and Adverse Reactions (6.1) ] .
- The data described in Table 4 reflect exposure to voriconazole in 1655 patients in nine therapeutic studies.
- This represents a heterogeneous population, including immunocompromised patients, e.g., patients with hematological malignancy or HIV and non-neutropenic patients.
- This subgroup does not include healthy subjects and patients treated in the compassionate use and non-therapeutic studies.
- This patient population was 62% male, had a mean age of 46 years (range 11–90, including 51 patients aged 12–18 years), and was 78% White and 10% Black.
- Five hundred sixty one patients had a duration of voriconazole therapy of greater than 12 weeks, with 136 patients receiving voriconazole for over six months.
- Table 4 includes all adverse reactions which were reported at an incidence of ≥2% during voriconazole therapy in the all therapeutic studies population, studies 307/602 and 608 combined, or study 305, as well as events of concern which occurred at an incidence of <2%.
- In study 307/602, 381 patients (196 on voriconazole, 185 on amphotericin B) were treated to compare voriconazole to amphotericin B followed by other licensed antifungal therapy (OLAT) in the primary treatment of patients with acute IA.
- The rate of discontinuation from voriconazole study medication due to adverse reactions was 21.4% (42/196 patients).
- In study 608, 403 patients with candidemia were treated to compare voriconazole (272 patients) to the regimen of amphotericin B followed by fluconazole (131 patients).
- The rate of discontinuation from voriconazole study medication due to adverse reactions was 19.5% out of 272 patients.
- Study 305 evaluated the effects of oral voriconazole (200 patients) and oral fluconazole (191 patients) in the treatment of EC.
Use
Indications
- 2 years of age and older with: • Invasive aspergillosis ( 1.1 ) • Candidemia in non-neutropenics and other deep tissue Candida infections ( 1.2 ) • Esophageal candidiasis ( 1.3 ) • Serious fungal infections caused by Scedosporium apiospermum and Fusarium species including Fusarium solani , in patients intolerant of, or refractory to, other therapy ( 1.4 ) 1.1 Invasive Aspergillosis VFEND is indicated in adults and pediatric patients (2 years of age and older) for the treatment of invasive aspergillosis (IA).
- In clinical trials, the majority of isolates recovered were Aspergillus fumigatus .
- There was a small number of cases of culture-proven disease due to species of Aspergillus other than A. fumigatus [see Clinical Studies (14.1 , 14.5) and Microbiology (12.4) ] . 1.2 Candidemia in Non-neutropenic Patients and Other Deep Tissue Candida Infections VFEND is indicated in adults and pediatric patients (2 years of age and older) for the treatment of candidemia in non-neutropenic patients and the following Candida infections: disseminated infections in skin and infections in abdomen, kidney, bladder wall, and wounds [see Clinical Studies (14.2 , 14.5) and Microbiology (12.4) ] . 1.3 Esophageal Candidiasis VFEND is indicated in adults and pediatric patients (2 years of age and older) for the treatment of esophageal candidiasis (EC) [see Clinical Studies (14.3 , 14.5) and Microbiology (12.4) ] . 1.4 Scedosporiosis and Fusariosis VFEND is indicated for the treatment of serious fungal infections caused by Scedosporium apiospermum (asexual form of Pseudallescheria boydii ) and Fusarium spp. including Fusarium solani , in adults and pediatric patients (2 years of age and older) intolerant of, or refractory to, other therapy [see Clinical Studies (14.4) and Microbiology (12.4) ] . 1.5 Usage Specimens for fungal culture and other relevant laboratory studies (including histopathology) should be obtained prior to therapy to isolate and identify causative organism(s).
- Therapy may be instituted before the results of the cultures and other laboratory studies are known.
- However, once these results become available, antifungal therapy should be adjusted accordingly.
Pharmacology
Mode of action
Voriconazole is an antifungal drug [see Microbiology (12.
Full mechanism text
Voriconazole is an antifungal drug [see Microbiology (12.4) ]. 12.2 Pharmacodynamics Exposure-Response Relationship for Efficacy and Safety In 10 clinical trials (N=1121), the median values for the average and maximum voriconazole plasma concentrations in individual patients across these studies was
ADME
Pharmacokinetics & PD
| Onset | Days for clinical response (varies) |
|---|---|
| Duration | Days–weeks per indication |
| Route | INTRAVENOUS |
| Absorption | The pharmacokinetic properties of voriconazole are similar following administration by the intravenous and oral routes. Based on a population pharmacokinetic analysis of pooled data in healthy subjects (N=207), the oral bioavailability of voriconazole is estimated to be 96% (CV 1... |
| Distribution | The volume of distribution at steady state for voriconazole is estimated to be 4.6 L/kg, suggesting extensive distribution into tissues. Plasma protein binding is estimated to be 58% and was shown to be independent of plasma concentrations achieved following single and multiple o... |
| Metabolism | In vitro studies showed that voriconazole is metabolized by the human hepatic cytochrome P450 enzymes, CYP2C19, CYP2C9 and CYP3A4 [see Drug Interactions (7) ] . In vivo studies indicated that CYP2C19 is significantly involved in the metabolism of voriconazole. This enzyme exhibit... |
| Elimination | Metabolism In vitro studies showed that voriconazole is metabolized by the human hepatic cytochrome P450 enzymes, CYP2C19, CYP2C9 and CYP3A4 [see Drug Interactions (7) ] . In vivo studies indicated that CYP2C19 is significantly involved in the |
| Half-life | of voriconazole is dose dependent and therefore not useful in predicting the accumulation or |
Full PK/PD text
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Voriconazole is an antifungal drug [see Microbiology (12.4) ]. 12.2 Pharmacodynamics Exposure-Response Relationship for Efficacy and Safety In 10 clinical trials (N=1121), the median values for the average and maximum voriconazole plasma concentrations in individual patients across these studies was 2.51 µg/mL (inter-quartile range 1.21 to 4.44 µg/mL) and 3.79 µg/mL (inter-quartile range 2.06 to 6.31 µg/mL), respectively. A pharmacokinetic-pharmacodynamic analysis of patient data from 6 of these 10 clinical trials (N=280) could not detect a positive association between mean, maximum or minimum plasma voriconazole concentration and efficacy. However, pharmacokinetic/pharmacodynamic analyses of the data from all 10 clinical trials identified positive associations between plasma voriconazole concentrations and rate of both liver function test abnormalities and visual disturbances [see Adverse Reactions (6) ] . Cardiac Electrophysiology A placebo-controlled, randomized, crossover study to evaluate the effect on the QT interval of healthy male and female subjects was conducted with three single oral doses of voriconazole and ketoconazole. Serial ECGs and plasma samples were obtained at specified intervals over a 24-hour post dose observation period. The placebo-adjusted mean maximum increases in QTc from baseline after 800, 1200, and 1600 mg of voriconazole and after ketoconazole 800 mg were all <10 msec. Females exhibited a greater increase in QTc than males, although all mean changes were <10 msec. Age was not found to affect the magnitude of increase in QTc. No subject in any group had an increase in QTc of ≥60 msec from baseline. No subject experienced an interval exceeding the potentially clinically relevant threshold of 500 msec. However, the QT effect of voriconazole combined with drugs known to prolong the QT interval is unknown [see Contraindications (4) and Drug Interactions (7) ] . 12.3 Pharmacokinetics The pharmacokinetics of voriconazole have been characterized in healthy subjects, special populations and patients. The pharmacokinetics of voriconazole are non-linear due to saturation of its metabolism. The interindividual variability of voriconazole pharmacokinetics is high. Greater than proportional increase in exposure is observed with increasing dose. It is estimated that, on average, increasing the oral dose from 200 mg every 12 hours to 300 mg every 12 hours leads to an approximately 2.5-fold increase in exposure (AUC τ ); similarly, increasing the intravenous dose from 3 mg/kg every 12 hours to 4 mg/kg every 12 hours produces an approximately 2.5-fold increase in exposure (Table 12). Table 12: Geometric Mean (%CV) Plasma Voriconazole Pharmacokinetic Parameters in Adults Receiving Different Dosing Regimens Note: Parameters were estimated based on non-compartmental analysis from 5 pharmacokinetic studies. AUC 12 = area under the curve over 12 hour dosing interval, C max = maximum plasma concentration, C min = minimum plasma concentration. CV = coefficient of variation. 6 mg/kg IV (loading dose) 3 mg/kg IV every 12 hours 4 mg/kg IV every 12 hours 400 mg Oral (loading dose) 200 mg Oral every 12 hours 300 mg Oral every 12 hours N 35 23 40 17 48 16 AUC 12 (μg∙h/mL) 13.9 (32) 13.7 (53) 33.9 (54) 9.31 (38) 12.4 (78) 34.0 (53) C max (μg/mL) 3.13 (20) 3.03 (25) 4.77 (36) 2.30 (19) 2.31 (48) 4.74 (35) C min (μg/mL) -- 0.46 (97) 1.73 (74) -- 0.46 (120) 1.63 (79) When the recommended intravenous loading dose regimen is administered to healthy subjects, plasma concentrations close to steady state are achieved within the first 24 hours of dosing (e.g., 6 mg/kg IV every 12 hours on day 1 followed by 3 mg/kg IV every 12 hours). Without the loading dose, accumulation occurs during twice daily multiple dosing with steady- state plasma voriconazole concentrations being achieved by day 6 in the majority of subjects. Absorption The pharmacokinetic properties of voriconazole are similar following administration by the intravenous and oral routes. Based on a population pharmacokinetic analysis of pooled data in healthy subjects (N=207), the oral bioavailability of voriconazole is estimated to be 96% (CV 13%). Maximum plasma concentrations (C max ) are achieved 1–2 hours after dosing. When multiple doses of voriconazole are administered with high-fat meals, the mean C max and AUC τ are reduced by 34% and 24%, respectively when administered as a tablet and by 58% and 37% respectively when administered as the oral suspension [see Dosage and Administration (2) ] . In healthy subjects, the absorption of voriconazole is not affected by coadministration of oral ranitidine, cimetidine, or omeprazole, drugs that are known to increase gastric pH. Distribution The volume of distribution at steady state for voriconazole is estimated to be 4.6 L/kg, suggesting extensive distribution into tissues. Plasma protein binding is estimated to be 58% and was shown to be independent of plasma concentrations achieved following single and multiple oral doses of 200 mg or 300 mg (approximate range: 0.9–15 µg/mL). Varying degrees of hepatic and renal impairment do not affect the protein binding of voriconazole. Elimination Metabolism In vitro studies showed that voriconazole is metabolized by the human hepatic cytochrome P450 enzymes, CYP2C19, CYP2C9 and CYP3A4 [see Drug Interactions (7) ] . In vivo studies indicated that CYP2C19 is significantly involved in the metabolism of voriconazole. This enzyme exhibits genetic polymorphism [see Clinical Pharmacology (12.5) ] . The major metabolite of voriconazole is the N-oxide, which accounts for 72% of the circulating radiolabelled metabolites in plasma. Since this metabolite has minimal antifungal activity, it does not contribute to the overall efficacy of voriconazole. Excretion Voriconazole is eliminated via hepatic metabolism with less than 2% of the dose excreted unchanged in the urine. After administration of a single radiolabelled dose of either oral or IV voriconazole, preceded by multiple oral or IV dosing, approximately 80% to 83% of the radioactivity is recovered in the urine. The majority (>94%) of the total radioactivity is excreted in the first 96 hours after both oral and intravenous dosing. As a result of non-linear pharmacokinetics, the terminal half-life of voriconazole is dose dependent and therefore not useful in predicting the accumulation or elimination of voriconazole. Specific Populations Male and Female Patients In a multiple oral dose study, the mean C max and AUC τ for healthy young females were 83% and 113% higher, respectively, than in healthy young males (18–45 years), after tablet dosing. In the same study, no significant differences in the mean C max and AUC τ were observed between healthy elderly males and healthy elderly females (>65 years). In a similar study, after dosing with the oral suspension, the mean AUC for healthy young females was 45% higher than in healthy young males whereas the mean C max was comparable between genders. The steady state trough voriconazole concentrations (C min ) seen in females were 100% and 91% higher than in males receiving the tablet and the oral suspension, respectively. In the clinical program, no dosage adjustment was made on the basis of gender. The safety profile and plasma concentrations observed in male and female subjects were similar. Therefore, no dosage adjustment based on gender is necessary. Geriatric Patients In an oral multiple dose study the mean C max and AUC τ in healthy elderly males (≥65 years) were 61% and 86% higher, respectively, than in young males (18–45 years). No significant differences in the mean C max and AUC τ were observed between healthy elderly females (≥65 years) and healthy young females (18–45 years). In the clinical program, no dosage adjustment was made on the basis of age. An analysis of pharmacokinetic data obtained from 552 patients from 10 voriconazole clinical trials showed that the median voriconazole plasma concentrations in the elderly patients (>65 years) were approximately 80% to 90% higher than those in the younger patients (≤65 years) after either IV or oral administration. However, the safety profile of voriconazole in young and elderly subjects was similar and, therefore, no dosage adjustment is necessary for the elderly [see Use in Special Populations (8.5) ] . Pediatric Patients The recommended doses in pediatric patients were based on a population pharmacokinetic analysis of data obtained from 112 immunocompromised pediatric patients aged 2 to less than 12 years and 26 immunocompromised pediatric patients aged 12 to less than 17 years. A comparison of the pediatric and adult population pharmacokinetic data indicated that the predicted total exposure (AUC 12 ) in pediatric patients aged 2 to less than 12 years following administration of a 9 mg/kg intravenous loading dose was comparable to that in adults following a 6 mg/kg intravenous loading dose. The predicted total exposures in pediatric patients aged 2 to less than 12 years following intravenous maintenance doses of 4 and 8 mg/kg twice daily were comparable to those in adults following 3 and 4 mg/kg IV twice daily, respectively. The predicted total exposure in pediatric patients aged 2 to less than 12 years following an oral maintenance dose of 9 mg/kg (maximum of 350 mg) twice daily was comparable to that in adults following 200 mg oral twice daily. An 8 mg/kg intravenous dose will provide voriconazole exposure approximately 2-fold higher than a 9 mg/kg oral dose in pediatric patients aged 2 to less than 12 years. Voriconazole exposures in the majority of pediatric patients aged 12 to less than 17 years were comparable to those in adults receiving the same dosing regimens. However, lower voriconazole exposure was observed in some pediatric patients aged 12 to less than 17 years with low body weight compared to adults [see Dosage and Administration (2.4) ] . Limited voriconazole trough plasma samples were collected in pediatric patients aged 2 to less than 18 years with IA or invasive candidiasis including candidemia, and EC in two prospective, open-label, non-comparative, multicenter clinical studies. In eleven pediatric patients aged 2 to less than 12 years and aged 12 to 14 years, with body weight less than 50 kg, who received 9 mg/kg intravenously every 12 hours as a loading dose on the first day of treatment, followed by 8 mg/kg every 12 hours as an intravenous maintenance dose, or 9 mg/kg every 12 hours as an oral maintenance dose, the mean trough concentration of voriconazole was 3.6 mcg/mL (range 0.3 to 10.7 mcg/mL). In four pediatric patients aged 2 to less than 12 years and aged 12 to 14 years, with body weight less than 50 kg, who received 4 mg/kg intravenously every 12 hours, the mean trough concentration of voriconazole was 0.9 mcg/mL (range 0.3 to 1.6 mcg/mL) [see Clinical Studies (14.5) ] . Patients with Hepatic Impairment After a single oral dose (200 mg) of voriconazole in 8 patients with mild (Child-Pugh Class A) and 4 patients with moderate (Child-Pugh Class B) hepatic impairment, the mean systemic exposure (AUC) was 3.2-fold higher than in age and weight matched controls with normal hepatic function. There was no difference in mean peak plasma concentrations (C max ) between the groups. When only the patients with mild (Child-Pugh Class A) hepatic impairment were compared to controls, there was still a 2.3-fold increase in the mean AUC in the group with hepatic impairment compared to controls. In an oral multiple dose study, AUC τ was similar in 6 subjects with moderate hepatic impairment (Child-Pugh Class B) given a lower maintenance dose of 100 mg twice daily compared to 6 subjects with normal hepatic function given the standard 200 mg twice daily maintenance dose. The mean peak plasma concentrations (C max ) were 20% lower in the hepatically impaired group. No pharmacokinetic data are available for patients with se
Kenya
Brands & prices
| Brand | Company | Pack | KES |
|---|---|---|---|
| Vfend | Pfizer Global Pharmaceuticals | Standard Commercial Pack | — |
| Vorifun | Unicorn Pharma | Standard Commercial Pack | — |
| Voriglax | Meyer Organics | Standard Commercial Pack | — |
| Vozole (Voricozole powder for eye drops) | Aurolab | Standard Commercial Pack | — |
Special populations
Pregnancy & lactation
Pregnancy
8.1 Pregnancy Risk Summary Voriconazole can cause fetal harm when administered to a pregnant woman. There are no available data on the use of VFEND in pregnant women. In animal reproduction studies, oral voriconazole was associated with fetal malformations in rats and fetal toxicity in rabbits. Cleft palates and hydronephrosis/hydroureter were observed in rat pups exposed to voriconazole during organogenesis at and above 10 mg/kg (0.3 times the RMD of 200 mg every 12 hours based on body surface area comparisons). In rabbits, embryomortality, reduced fetal weight and increased incidence of skeletal variations, cervical ribs and extrasternal ossification sites were observed in pups when pregnant rabbits were orally dosed at 100 mg/kg (6 times the RMD based on body surface area comparisons) during organogenesis. Rats exposed to voriconazole from implantation to weaning experienced increased gestational length and dystocia, which were associated with increased perinatal pup mortality at the 10 mg/kg dose [see Data ] . If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, inform the patient of the potential hazard to the fetus [see Warnings and Precautions (5.9) ] . The background risk of major birth defects and miscarriage for the indicated populations is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20% respectively. Data Animal Data Voriconazole was administered orally to pregnant rats during organogenesis (gestation days 6–17) at 10, 30, and 60 mg/kg/day. Voriconazole was associated with increased incidences of the malformations hydroureter and hydronephrosis at 10 mg/kg/day or greater, approximately 0.3 times the recommended human dose (RMD) based on body surface area comparisons, and cleft palate at 60 mg/kg , approximately 2 times the RMD based on body surface area comparisons. Reduced ossification of sacral and caudal vertebrae, skull, pubic, and hyoid bone, supernumerary ribs, anomalies of the sternebrae, and dilatation of the ureter/renal pelvis were also observed at doses of 10 mg/kg or greater. There was no evidence of maternal toxicity at any dose. Voriconazole was administered orally to pregnant rabbits during the period of organogenesis (gestation days 7–19) at 10, 40, and 100 mg/kg/day. Voriconazole was associated with increased post-implantation loss and decreased fetal body weight, in association with maternal toxicity (decreased body weight gain and food consumption) at 100 mg/kg/day (6 times the RMD based on body surface area comparisons). Fetal skeletal variations (increases in the incidence of cervical rib and extra sternebral ossification sites) were observed at 100 mg/kg/day. In a peri- and postnatal toxicity study in rats, voriconazole was administered orally to female rats from implantation through the end of lactation at 1, 3, and 10 mg/kg/day. Voriconazole prolonged the duration of gestation and labor and produced dystocia with related increases in maternal mortality and decreases in perinatal survival of F1 pups at 10 mg/kg/day, approximately 0.3 times the RMD.
Lactation
• Pediatrics : Safety and effectiveness in patients younger than 2 years has not been established ( 8.4 ) 8.1 Pregnancy Risk Summary Voriconazole can cause fetal harm when administered to a pregnant woman. There are no available data on the use of VFEND in pregnant women. In animal reproduction studies, oral voriconazole was associated with fetal malformations in rats and fetal toxicity in rabbits. Cleft palates and hydronephrosis/hydroureter were observed in rat pups exposed to voriconazole during organogenesis at and above 10 mg/kg (0.3 times the RMD of 200 mg every 12 hours based on body surface area comparisons). In rabbits, embryomortality, reduced fetal weight and increased incidence of skeletal variations, cervical ribs and extrasternal ossification sites were observed in pups when pregnant rabbits were orally dosed at 100 mg/kg (6 times the RMD based on body surface area comparisons) during organogenesis. Rats exposed to voriconazole from implantation to weaning experienced increased gestational length and dystocia, which were associated with increased perinatal pup mortality at the 10 mg/kg dose [see Data ] . If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, inform the patient of the potential hazard to the fetus [see Warnings and Precautions (5.9) ] . The background risk of major birth defects and miscarriage for the indicated populations is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20% respectively. Data Animal Data Voriconazole was administered orally to pregnant rats during organogenesis (gestation days 6–17) at 10, 30, and 60 mg/kg/day. Voriconazole was associated with increased incidences of the malformations hydroureter and hydronephrosis at 10 mg/kg/day or greater, approximately 0.3 times the recommended human dose (RMD) based on body surface area comparisons, and cleft palate at 60 mg/kg , approximately 2 times the RMD based on body surface area comparisons. Reduced ossification of sacral and caudal vertebrae, skull, pubic, and hyoid bone, supernumerary ribs, anomalies of the sternebrae, and dilatation of the ureter/renal pelvis were also observed at doses of 10 mg/kg or greater. There was no evidence of maternal toxicity at any dose. Voriconazole was administered orally to pregnant rabbits during the period of organogenesis (gestation days 7–19) at 10, 40, and 100 mg/kg/day. Voriconazole was associated with increased post-implantation loss and decreased fetal body weight, in association with maternal toxicity (decreased body weight gain and food consumption) at 100 mg/kg/day (6 times the RMD based on body surface area comparisons). Fetal skeletal variations (increases in the incidence of cervical rib and extra sternebral ossification sites) were observed at 100 mg/kg/day. In a peri- and postnatal toxicity study in rats, voriconazole was administered orally to female rats from implantation through the end of lactation at 1, 3, and 10 mg/kg/day. Voriconazole prolonged the duration of gestation and labor and produced dystocia with related increases in maternal mortality and decreases in perinatal survival of F1 pups at 10 mg/kg/day, approximately 0.3 times the RMD. 8.2 Lactation Risk Summary No data are available regarding the presence of voriconazole in human milk, the effects of voriconazole on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for VFEND and any potential adverse effects on the breastfed child from VFEND or from the underlying maternal condition. 8.3 Females and Males of Reproductive Potential Contraception Advise females of reproductive potential to use effective contraception during treatment with VFEND. The coadministration of voriconazole with the oral contraceptive, Ortho-Novum ® (35 mcg ethinyl estradiol and 1 mg norethindrone), results in an interaction between these two drugs, but is unlikely to reduce the contraceptive effect. Monitoring for adverse reactions associated with oral contraceptives and voriconazole is recommended [see Drug Interactions (7) and Clinical Pharmacology (12.3) ] . 8.4 Pediatric Use The safety and effectiveness of VFEND have been established in pediatric patients 2 years of age and older based on evidence from adequate and well-controlled studies in adult and pediatric patients and additional pediatric pharmacokinetic and safety data. A total of 105 pediatric patients aged 2 to less than 12 [N=26] and aged 12 to less than 18 [N=79] from two, non-comparative Phase 3 pediatric studies and eight adult therapeutic trials provided safety information for VFEND use in the pediatric population [see Adverse Reactions (6.1) , Clinical Pharmacology (12.3) , and Clinical Studies (14) ] . Safety and effectiveness in pediatric patients below the age of 2 years has not been established. Therefore, VFEND is not recommended for pediatric patients less than 2 years of age. A higher frequency of liver enzyme elevations was observed in the pediatric patients [see Dosage and Administration (2.5) , Warnings and Precautions (5.1) , and Adverse Reactions (6.1) ] . The frequency of phototoxicity reactions is higher in the pediatric population. Squamous cell carcinoma has been reported in patients who experience photosensitivity reactions. Stringent measures for photoprotection are warranted. Sun avoidance and dermatologic follow-up are recommended in pediatric patients experiencing photoaging injuries, such as lentigines or ephelides, even after treatment discontinuation [see Warnings and Precautions (5.6) ]. VFEND has not been studied in pediatric patients with hepatic or renal impairment [see Dosage and Administration (2.5 , 2.6) ] . Hepatic function and serum creatinine levels should be closely monitored in pediatric patients [see Dosage and Administration (2.6) and Warnings and Precautions (5.1 , 5.10) ] . 8.5 Geriatric Use In multiple dose therapeutic trials of voriconazole, 9.2% of patients were ≥65 years of age and 1.8% of patients were ≥75 years of age. In a study in healthy subjects, the systemic exposure (AUC) and peak plasma concentrations (C max ) were increased in elderly males compared to young males. Pharmacokinetic data obtained from 552 patients from 10 voriconazole therapeutic trials showed that voriconazole plasma concentrations in the elderly patients were approximately 80% to 90% higher than those in younger patients after either IV or oral administration. However, the overall safety profile of the elderly patients was similar to that of the young so no dosage adjustment is recommended [see Clinical Pharmacology (12.3) ] .
Diet
Food & alcohol
- Drug & food interactions (label) 7 DRUG INTERACTIONS Voriconazole is metabolized by cytochrome P450 isoenzymes, CYP2C19, CYP2C9, and CYP3A4. Therefore, inhibitors or inducers of these isoenzymes may increase or decrease voriconazole plasma concentrations, respectively. Voriconazole is a strong inhibitor of CYP3A4, and also inhibits CYP2C19 and CYP2C9. Therefore, voriconazole may increase the plasma concentrations of substances metabolized by these CYP450 isoenzymes. Table 10 and Table 11 provide listings of clinically significant drug interactions, including contraindicated drugs [see Contraindications (4) ] . Drugs listed in Table 10 and Table 11 are a guide and not considered a comprehensive list of all possible drugs and herbal products that are contraindicated or may interact with VFEND. Table 10: Effect of Other Drugs on Voriconazole Pharmacokinetics [see Clinical Pharmacology (12.3)] Drug/Drug Class (Mechanism of Interaction by the Drug) Voriconazole Plasma Exposure (C max and AUC τ after 200 mg every 12 hours) Prevention or Management Recommendations Rifampin Results based on in vivo clinical studies generally following repeat oral dosing with 200 mg every 12 hours voriconazole to healthy subjects and Rifabutin (CYP450 Induction) Significantly Reduced Contraindicated Efavirenz (400 mg every 24 hours) Results based on in vivo clinical study following repeat oral dosing with 400 mg every 12 hours for 1 day, then 200 mg every 12 hours for at least 2 days voriconazole to healthy subjects (CYP450 Induction) Significantly Reduced Contraindicated Efavirenz (300 mg every 24 hours) (CYP450 Induction) Slight Decrease in AUC τ When voriconazole is concomitantly administered with efavirenz, voriconazole oral maintenance dose should be increased to 400 mg every 12 hours and efavirenz should be decreased to 300 mg every 24 hours. High-dose Ritonavir (400 mg every 12 hours) (CYP450 Induction) Significantly Reduced Contraindicated Low-dose Ritonavir (100 mg every 12 hours) (CYP450 Induction) Reduced Concomitant administration of voriconazole and low-dose ritonavir (100 mg every 12 hours) should be avoided, unless an assessment of the benefit/risk to the patient justifies the use of voriconazole. Carbamazepine (CYP450 Induction) Not Studied In Vivo or In Vitro , but Likely to Result in Significant Reduction Contraindicated Long Acting Barbiturates (e.g., phenobarbital, mephobarbital) (CYP450 Induction) Not Studied In Vivo or In Vitro , but Likely to Result in Significant Reduction Contraindicated Phenytoin (CYP450 Induction) Significantly Reduced Increase voriconazole maintenance dose from 4 mg/kg to 5 mg/kg IV every 12 hours or from 200 mg to 400 mg orally every 12 hours (100 mg to 200 mg orally every 12 hours in patients weighing less than 40 kg). Letermovir (CYP2C9/2C19 Induction) Reduced If concomitant administration of voriconazole with letermovir cannot be avoided, monitor for reduced effectiveness of voriconazole. St. John's Wort (CYP450 inducer; P-gp inducer) Significantly Reduced
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Sources & disclaimer
Source: Local active-ingredient clinical extract; FDA drug label via OpenFDA/DailyMed; Professional class pharmacology (Antifungal)
Last reviewed: 01 Aug 2026
Decision support only — not a substitute for clinical judgment, product SmPC, or Kenya STG/EML.