Drug interactions
Probenecid + Valacyclovir
Severity: Minor
Probenecid and Valacyclovir: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Probenecid reduces the renal tubular secretion of acyclovir, the active metabolite of valacyclovir, leading to higher and more prolonged acyclovir exposure. This is usually of limited clinical significance at standard doses but may matter in patients with renal impairment.
What this interaction means in plain words
Probenecid and Valacyclovir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Probenecid belongs to Genitourinary; Valacyclovir belongs to Anti Virals.
Why it happens
Probenecid inhibits renal organic anion transporters involved in tubular secretion of acyclovir, decreasing its renal clearance.
What to do
No routine dose change is needed with normal renal function. In renal impairment, monitor for acyclovir neurotoxicity such as confusion or tremor and adjust the valacyclovir dose.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Probenecid
- Ketorolac intranasal + Probenecid Contraindicated
- Ketorolac + Probenecid Contraindicated
- Baricitinib + Probenecid Major
- Ceftazidime / avibactam + Probenecid Major
- Methotrexate + Probenecid Major
- Pralatrexate + Probenecid Major
Other interactions of Valacyclovir
- Talimogene laherparepvec + Valacyclovir Major
- Bacitracin + Valacyclovir Moderate
- Cilastatin-imipenem + Valacyclovir Moderate
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Valacyclovir Moderate
- Imipenem / cilastatin / relebactam + Valacyclovir Moderate
- Imipenem / cilastatin + Valacyclovir Moderate
Frequently asked questions
Can I take Probenecid with Valacyclovir?
MediHelp rates the interaction as minor. Probenecid and Valacyclovir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Probenecid reduces the renal tubular secretion of acyclovir, the active metabolite of valacyclovir, leading to higher and more prolonged acyclovir exposure. This is usually of limited clinical significance at standard doses but may matter in patients with renal impairment.
How serious is the interaction between Probenecid and Valacyclovir?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No routine dose change is needed with normal renal function. In renal impairment, monitor for acyclovir neurotoxicity such as confusion or tremor and adjust the valacyclovir dose.
What other medicines interact with Probenecid?
MediHelp also lists interactions of Probenecid with, for example, Ketorolac intranasal, Ketorolac, Baricitinib. The full list is on the Probenecid page.
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