When does Acyclovir expire? 

When does Acyclovir expire? 

Acyclovir comes with an expiry date of 3 years from the manufacturing date. This antiviral can outlive its expiration date if it is stored properly. 

However, it is not recommended by the FDA to use expired antiviral medications, especially during the multiplication phase of your viral infection where you need a fully potent antiviral medication to fight against the spreading growth of the virus (1). 

What are the possible dangers associated with the use of expired Acyclovir? 

Expired Acyclovir is not considered harmful to your health as it does not directly cause any side effects. However, it will not benefit your condition either.

Expired Acyclovir will most definitely start to lose its potency and there’s no way to tell when that process begins and what factors affect the rate of drug degradation. This is why it’s best to opt for an unexpired Acyclovir for an active viral infection. 

What to do if you have taken expired Acyclovir? 

If you have taken expired Acyclovir, don’t worry. The drug won’t harm you and that’s not even the question. The main question is; Will it work? 

I’d recommend talking to your healthcare provider and getting a proper diagnosis. Your doctor will give out another prescription and it will surely work out for the best. 

Make sure you take Acyclovir in the best possible way. You can crush the tablet and mix it with soft foods for ease of administration. However, it’s best to talk to your doctor or pharmacist if you’re confused about the right way to use Acyclovir.

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U.S. Food and Drug Administration. Don’t Be Tempted to Use Expired Medicines [Internet]. Silver Spring (MD): U.S. Food and Drug Administration; 2021 [cited 2022 Oct 27]. Available from: https://www.fda.gov/drugs/special-features/dont-be-tempted-use-expired-medicines.