Can Cold sore treatment interact with my other medicines or vaccines?

Before taking valacyclovir, share a complete medicine list with your prescribing physician and pharmacist. Include medicines you use only sometimes, such as pain relievers, as well as vitamins and supplements. Mention kidney disease or recent dehydration because these can change the safety of some combinations.

Medicines that affect the kidneys may need extra review. Examples include some immune-suppressing drugs, certain antibiotics, and anti-inflammatory pain relievers such as ibuprofen or naproxen. This does not mean every combination is unsafe. Your physician will review the dose, how often you use it, and your health history. Do not stop a prescribed medicine without advice.

Tell your physician if you already take acyclovir, valacyclovir, or another antiviral. Taking overlapping treatments can lead to an unintended extra dose. Valacyclovir can also interfere with certain live varicella vaccines, including the live chickenpox vaccine. Let the vaccine provider know before vaccination so they can advise on timing. Ask your pharmacist to review any new medicine before you add it during treatment.