Clindamycin Vaginal and Voriconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Voriconazole
Clindamycin Vaginal
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased CYP3A4 substrates exposure and an increased efficacy of CYP3A4 substrates-related adverse effects
Interaction Deep Dive
Coadministration of voriconazole with CYP3A4 substrates may increase CYP3A4 substrates exposure which may increase the efficacy of these substrates. Reduce dosage of these substrates and monitor for adverse reactions. In an independent published study, concomitant use of voriconazole (400 mg every 12 hours on Day 1, then 200 mg every 12 hours on Day 2) with a single intravenous dose of fentaNYL (5 microgram/kg) resulted in an increase in the mean AUC (0 to inf) of fentaNYL by 1.4-fold (range 0.81- to 2.04-fold). In another independent published study, coadministration of multiple doses of oral voriconazole (400 mg every 12 hours, on Day 1 followed by five doses of 200 mg every 12 hours on Days 2 to 4) with a single 10 mg oral dose of oxyCODONE on Day 3 resulted in an increase in the mean Cmax and AUC (0 to inf) of oxyCODONE by 1.7-fold (range 1.4- to 2.2-fold) and 3.6- fold (range 2.7- to 5.6-fold), respectively. The mean elimination half-life of oxyCODONE was also increased by 2.0-fold (range 1.4- to 2.5-fold). In stable renal transplant recipients receiving chronic cycloSPORINE therapy, concomitant administration of oral voriconazole (200 mg every 12 hours for 8 days) increased cycloSPORINE Cmax and AUC (tau) an average of 1.1 times (90% CI: 0.9, 1.41) and 1.7 times (90% CI: 1.5, 2.0), respectively, as compared to when cycloSPORINE was administered without voriconazole1.
Why it happens (mechanism)
Inhibition of CYP3A4-substrate metabolism by voriconazole
Literature reports
3 reports — tap to read
a) In an independent published study, concomitant use of voriconazole (400 mg every 12 hours on Day 1, then 200 mg every 12 hours on Day 2) with a single intravenous dose of fentaNYL (CYP3A4 substrate) (5 microgram/kg) resulted in an increase in the mean AUC (0 to inf) of fentaNYL by 1.4-fold (range 0.81- to 2.04-fold) 1.
b) In another independent published study, coadministration of multiple doses of oral voriconazole (400 mg every 12 hours, on Day 1 followed by five doses of 200 mg every 12 hours on Days 2 to 4) with a single 10 mg oral dose of oxyCODONE (CYP3A4 substrate) on Day 3 resulted in an increase in the mean Cmax and AUC (0 to inf) of oxyCODONE by 1.7-fold (range 1.4- to 2.2-fold) and 3.6- fold (range 2.7- to 5.6-fold), respectively. The mean elimination half-life of oxyCODONE was also increased by 2.0-fold (range 1.4- to 2.5-fold) 1.
c) In stable renal transplant recipients receiving chronic cycloSPORINE (CYP3A4 substrate) therapy, concomitant administration of oral voriconazole (200 mg every 12 hours for 8 days) increased cycloSPORINE Cmax and AUC (tau) an average of 1.1 times (90% CI: 0.9, 1.41) and 1.7 times (90% CI: 1.5, 2.0), respectively, as compared to when cycloSPORINE was administered without voriconazole 1.
Common questions
Can I take Clindamycin Vaginal and Voriconazole together?
Increased CYP3A4 substrates exposure and an increased efficacy of CYP3A4 substrates-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Clindamycin Vaginal and Voriconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Clindamycin Vaginal or Voriconazole need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: VFEND(R) oral tablets, oral suspension, intravenous injection, voriconazole oral tablets, oral suspension, intravenous injection. Roerig (per FDA), New York, NY, 2025. DailyMed
Keep reading about Voriconazole
Keep reading about Clindamycin Vaginal
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