Nucleoside antiviral
Acyclovir drug interactions: a practical overview
Drug interactions are the single biggest cause of preventable medication problems. Acyclovir (Acyclovir) interacts to varying degrees with several classes of medication and with a smaller list of foods. This page summarises the practically important ones at 200mg, 400mg, 800mg, framed for a real-world prescription review rather than an exhaustive PDF list.
High-priority interactions for Acyclovir
For Acyclovir, the most clinically relevant interactions are typically with strong CYP3A4 inhibitors and inducers, with cardiovascular medications (notably nitrates for several Nucleoside antiviral agents), with central nervous system depressants, and with medications affecting blood pressure or heart rate. Acyclovir is a guanosine analogue selectively phosphorylated by viral thymidine kinase to its monophosphate form, then by cellular kinases to acyclovir triphosphate.
Working with the pharmacist
A pharmacist review of all current medications is the practical safeguard against unintended interactions with Acyclovir. According to the prescribing information for Acyclovir, the full medication list — prescription, OTC, supplements and recreational substances — should be reviewed before starting and at every dose change at 200mg, 400mg, 800mg.
Frequently asked questions
What's the most important Acyclovir interaction to know? ▾
For most Nucleoside antiviral medications, the highest-priority interaction is with nitrate medications used for chest pain — this combination is often a hard contraindication. After that, strong CYP3A4 inhibitors (some antifungals, macrolides) are the next concern at routine 200mg, 400mg, 800mg doses.
Do I need to tell the pharmacist about supplements? ▾
Yes. Supplements and herbal products can interact with Acyclovir in ways that prescription drug-drug interaction databases miss. The pharmacist needs the complete picture — including supplements like St John's Wort, grapefruit-containing products and high-dose vitamins — to flag risks at 200mg, 400mg, 800mg.
Products containing Acyclovir
More on Acyclovir
- With alcoholAcyclovir and alcohol — is it safe to drink?
- With foodShould Acyclovir be taken with food?
- Side effectsAcyclovir side effects: common, rare and warning signs
- Dosage guideAcyclovir dosage guide: how much to take and when
- OnsetHow fast does Acyclovir start working?
- DurationHow long does Acyclovir last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.