Indinavir and St Johns Wort: Drug Interaction Guide
Quick answer: This is a major interaction — avoid combining Indinavir and St Johns Wort unless specifically directed by your doctor.
How Indinavir interacts with St Johns Wort
St John's wort is a potent inducer of CYP3A4 and P-glycoprotein, reducing indinavir plasma levels by approximately 57% and risking virological failure and resistance.
What you should do
Contraindicated. Discontinue St John's wort and allow at least 2 weeks for enzyme induction to resolve before relying on antiretroviral concentrations.
Key facts
Severity
Major — avoid combination
Mechanism
St John's wort is a potent inducer of CYP3A4 and P-glycoprotein, reducing indinavir plasma levels by approximately 57% a...
Action
Contraindicated. Discontinue St John's wort and allow at least 2 weeks for enzyme induction to resolve before relying on...
Frequently asked questions
Can I take Indinavir and St Johns Wort together?
No — this combination should generally be avoided. Contraindicated. Discontinue St John's wort and allow at least 2 weeks for enzyme induction to resolve before relying on antiretroviral concentrations.
What is the severity of this interaction?
The interaction between Indinavir and St Johns Wort is classified as Major — avoid combination. St John's wort is a potent inducer of CYP3A4 and P-glycoprotein, reducing indinavir plasma levels by approximately 57% and risking virological failure and resistance.
What should I do if I'm prescribed both?
Contraindicated. Discontinue St John's wort and allow at least 2 weeks for enzyme induction to resolve before relying on antiretroviral concentrations. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.