Does sildenafil expire, and does an old pill still work?

In short: yes, sildenafil expires. Every tablet is sold with an expiration date, and the FDA’s consumer advice is plain: “If your medicine has expired, do not use it” (FDA, Don’t Be Tempted to Use Expired Medicines). The natural follow-up, whether a tablet still works after that date, has only an indirect answer: stockpile testing of other drugs, not of sildenafil. Here is what the date means, how to store the tablets so the date holds, and what is actually known about using them after it.

Does sildenafil expire?

Yes, sildenafil expires, and the date on your package is the one that counts. The FDA describes the expiration date as “a critical part of deciding if the product is safe to use and will work as intended” (FDA). The date is printed on the label or stamped on the bottle or carton, sometimes after the letters “EXP.”

The Viagra prescribing information gives storage conditions but no shelf life in years; the date to go by is the one printed on your container (Viagra prescribing information, DailyMed). So “how long does sildenafil last on the shelf?” has a simple answer: until the date on your bottle, if it has been stored as labeled. That is a different question from how long a dose works in your body, which we cover in how long sildenafil lasts.

How long is sildenafil good for?

Sildenafil is good until the printed expiration date, and those dates tend to be set conservatively. A 2019 systematic review of drug stability past expiry notes that the shelf life behind an expiration date is “typically between 1 and 5 years and commonly set in a conservative manner” (Zilker et al., J Pharm Biomed Anal, 2019). The same review concluded it “seems to be reasonable for a large portion of drugs” to extend expiry dates beyond five years, a finding across many drug classes, not a sildenafil result.

Compounded tablets are a separate case, because each formulation has its own data. One small lab study made compounded sildenafil 100 mg rapid-dissolving tablets, stored them in amber blister packs at room temperature, and found potency stayed above 95% of label claim with no sign of breakdown over six months (Cheung et al., Int J Pharm Compd, 2021). That tells you about that formulation over that window, nothing more, so follow the date on whatever you were dispensed.

How should you store sildenafil?

Store sildenafil at ordinary room temperature, dry, and out of reach of children. The Viagra label’s storage line reads “Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F),” and the patient leaflet puts it as room temperature between 68°F and 77°F (Viagra prescribing information, DailyMed). The same label tells pharmacies to dispense it in tight, child-resistant containers, so the original bottle is the best place for it.

The FDA’s practical advice fills in the rest. A damp bathroom cabinet can reduce a medicine’s effectiveness even before its date, and a “cool, dry place such as a dresser drawer, storage box, closet shelf, or kitchen cabinet” is better, kept away from hot appliances and the sink (FDA). The FDA presents proper storage as one way to help a medicine stay safe and effective up to its expiration date, so the date assumes the tablets were kept as labeled.

Does expired sildenafil still work?

We found no published test of expired sildenafil, so the honest answer is that it is unknown. The closest evidence comes from two studies of other drugs. Evidence level in plain words: indirect, from lab potency testing of different medicines, with no data on sildenafil tablets and no human data on effect.

The first is the Shelf Life Extension Program, which the FDA runs for the US Department of Defense. Across 122 drug products and 3,005 lots, 88% were extended at least one year past their original date, by an average of 66 months, but the extra time was “highly variable,” and the authors concluded quality “can only be assured by periodic testing and systematic evaluation of each lot” (Lyon et al., J Pharm Sci, 2006). The authors frame the finding as applying to drugs that are properly stored, which a home medicine drawer may not be.

The second, a short research letter, tested eight medicines found in a retail pharmacy in their original unopened containers, 28 to 40 years past expiry. Twelve of the 14 compounds tested were still at 90% or more of the labeled amount; aspirin and amphetamine had fallen below it, as had phenacetin in one of two samples, and the authors could not confirm how the containers had been stored (Cantrell et al., Arch Intern Med, 2012). Sildenafil was not among the drugs tested.

Is expired sildenafil dangerous?

There is no evidence that expired sildenafil becomes toxic, but there is also no guarantee it is safe or works, which is the FDA’s point. The agency says expired products “can be less effective or risky due to a change in chemical composition or a decrease in strength” (FDA).

What sildenafil breaks down into has been looked at only in the lab. When researchers forced it to degrade in solution under oxidizing conditions, it formed sildenafil N-oxide, a known impurity, which in a rat study acted like sildenafil but less potently (Abdel-Kader et al., Sci Rep, 2021). That is animal and test-tube data from a forced-degradation experiment, not a test of tablets aged on a shelf, so it does not show what an old bottle contains. Whatever the tablet’s age, the label’s limits still apply: the maximum recommended dosing frequency is once per day, and sildenafil is contraindicated with nitrates in any form (Viagra prescribing information, DailyMed). Known effects are covered in our guide to ED medication side effects.

What should you do with expired sildenafil?

Take expired sildenafil to a drug take-back location or use a pre-paid mail-back envelope; the FDA calls these the preferred options. Many retail, hospital and clinic pharmacies have drop boxes, and the DEA runs National Prescription Drug Take-Back Day (FDA). If neither is available, check the FDA flush list, and if the medicine is not on it, follow the FDA’s instructions for household trash disposal.

Then replace it the normal way rather than stretching an old bottle. An expiration date assumes the drug was made and stored as labeled; where tablets come from is the theme of our explainer on whether generic ED medications are safe. For what a replacement prescription costs, see online ED treatment cost.

What the community is saying

We have no Community Insights summary for sildenafil yet, so this page does not quote or characterize what users report. What the published evidence supports for now: stockpile testing found many other drugs kept their potency past the date under controlled storage, no published study has tested expired sildenafil, and the FDA advises against using expired medicine.

Status: Sildenafil: Active ingredient is FDA-approved; compounded versions are not FDA-approved. What these status terms mean.