Do medicines really expire?

The date stamped on the box describes the sealed pack. Once you open, mix or dilute a medicine, a different and usually much shorter clock starts — and that number is printed on the same label, where practically nobody looks.

By the pharmaranks editorial teamReviewed against FDA drug labels (DailyMed) and the FDA's Shelf Life Extension Program sourcesUpdated Jul 27, 2026How we research

What the FDA’s own data shows

The best evidence on this is the FDA’s, from a programme it has run for the US Department of Defense for two decades. Testing 122 drug products across 3,005 lots, it found that 88% of lots were extended at least one year beyond their original expiry date, by an average of 66 months.

“The SLEP data supports the assertion that many drug products, if properly stored, can be extended past the expiration date. Due to the lot-to-lot variability, the stability and quality of extended drug products can only be assured by periodic testing and systematic evaluation of each lot.”

Read both halves. The date is conservative — and the variation between lots is exactly why it is not a number to second-guess with the bottle in your hand. Source: Lyon RC et al. Stability profiles of drug products extended beyond labeled expiration dates. J Pharm Sci. 2006;95(7):1549-60.

Where the clock is genuinely short

Ranked by the shortest period any of that drug’s labels allows once it is opened, mixed or diluted. The ranking is read out of the quoted sentence, so it cannot drift from the words it is based on.

Docetaxel1 hour
Sodium Chloride solution or 5% Dextrose solution) should be used within 4 hours (including the 1 hour intravenous administration).
Doxorubicin1 hour
If not used within 1 hour, discard the diluted product.
Bendamustine2 hours
Sodium Chloride Injection, USP, the final admixture is stable for 24 hours stored under refrigerated conditions at 2°C to 8°C (36°F to 46°F) or for 2 hours when stored at room temperature (15°C to 30°C or 59°F to 86°F) and room light.
Dinutuximab2 hours
If blood pressure remains stable for at least 2 hours, increase the infusion rate as tolerated up to a maximum rate of 1.
Entrectinib2 hours
Discard any unused suspension if not used within 2 hours of preparation.
Dexrazoxane3 hours
Following reconstitution with Sterile Water for Injection, USP, dexrazoxane for injection is stable for 30 minutes at room temperature or if storage is necessary, up to 3 hours from the time of reconstitution when stored under refrigeration, 2° to 8°C (36° to 46°F).
Ascorbic Acid4 hours
Dispense single doses to multiple patients in a pharmacy admixture program; use within 4 hours of puncture.
Cefazolin4 hours
DISCARD ANY UNUSED PORTION AFTER 4 HOURS .
Cefepime4 hours
Discard any unused portion after 4 HOURS .
Cefotaxime4 hours
Discard the reconstituted stock solution 4 hours after initial entry.
Cefoxitin4 hours
Discard any unused portion after 4 HOURS .
Ceftazidime4 hours
DISCARD ANY UNUSED PORTION AFTER 4 HOURS.
Ceftriaxone4 hours
Discard any unused portion after 4 HOURS .
Cefuroxime4 hours
DISCARD VIALS 4 HOURS AFTER INITIAL ENTRY .
Cysteine4 hours
Use within 4 hours of puncture.
Cytarabine4 hours
Discard any unused portion within 4 hours after initial closure entry.
Dactinomycin4 hours
Discard after 4 hours.
Decitabine4 hours
Diluted stored solution must be used within 4 hours from the time of preparation.
Epinephrine4 hours
Adrenalin diluted in 5 percent dextrose solutions or 5 percent dextrose and sodium chloride solutions are stable for 4 hours at room temperature or 24 hours under refrigerated conditions.
Etelcalcetide4 hours
Use within 4 hours and do not expose to direct sunlight if removed from the original carton.
Cefiderocol6 hours
Diluted FETROJA Infusion Solution The diluted FETROJA infusion solution in the infusion bag is stable for up to 6 hours at room temperature.
Ceftaroline Fosamil6 hours
Stability in Infusion Bag : Studies have shown that the constituted solution in the infusion bag should be used within 6 hours when stored at room temperature or within 24 hours when stored under refrigeration at 2ºC to 8ºC (36ºF to 46ºF).
Cisplatin6 hours
If diluted solution is not to be used within 6 hours, protect solution from light.
Dantrolene6 hours
The contents of the vial must be protected from direct light and used within 6 hours after reconstitution.
Alemtuzumab8 hours
Use within 8 hours after dilution.
Alteplase8 hours
If stored between 2-30°C (36-86°F), Activase may be used within 8 hours following reconstitution.
Cabazitaxel8 hours
9% sodium chloride solution or 5% dextrose solution) should be used within 8 hours at ambient temperature (including the one-hour infusion), or for a total of 24 hours (including the one-hour infusion) under the refrigerated conditions.
Carboplatin8 hours
When prepared as directed, carboplatin aqueous solutions are stable for 8 hours at room temperature (25°C).
Cetuximab8 hours
Discard any remaining solution in the infusion container after 8 hours at controlled room temperature or after 12 hours at 2° C to 8° C.
Dacarbazine8 hours
Use within 8 hours of reconstitution.

Every drug we hold an in-use limit for (86)

Frequently asked questions

Do medicines actually stop working on the expiry date?

Mostly not, and the largest dataset on this belongs to the FDA itself. Its Shelf Life Extension Program tested 122 drug products across 3,005 lots for the US Department of Defense; 88% of lots were extended at least a year past their original expiry, by an average of 66 months. The paper's own conclusion is the balanced one: many products, properly stored, can be extended — but because the variation between lots is large, that can only be confirmed by testing each lot. So the date is conservative, not arbitrary, and it is not a number you can safely second-guess at home.

Then what should I actually be looking at?

The in-use limit, which is a different number and is printed on the same label. The expiry date describes the sealed pack; the in-use limit starts when you open, mix or dilute it. Amoxicillin suspension is discarded 10 days after it is mixed. An insulin pen in use is discarded after 28 days even if medicine remains. Nitroglycerin is used within 8 weeks of first opening the bottle. Those are the numbers that decide whether what is in your cupboard still works, and they are quoted per product on the pages below.

Which medicines is it genuinely risky to keep past their limit?

The ones whose own labels impose the shortest clock — reconstituted antibiotic suspensions, insulin in use, nitroglycerin after opening, diluted injections. Those are listed first below, ranked by the shortest period any of that drug's labels allows. The ranking is read out of the quoted sentence itself, so it can never disagree with the words next to it.

Is a faded or discoloured tablet safe if it is in date?

Being in date is not the same as being intact. Heat and humidity — a bathroom cabinet is the worst common storage spot — degrade medicines faster than a calendar does, and the stability data behind any expiry date assumes the storage conditions printed on the pack. Anything that has changed colour, smell, or texture should go to a pharmacist regardless of the date.

Where do these numbers come from?

Each sentence is quoted from an FDA drug label on DailyMed and linked to it. We do not generalise: a limit printed on one manufacturer's suspension is stored against that product and shown with its name, because it is not a fact about the molecule.

Reference information quoted from FDA labels, not medical advice. Nothing here is a recommendation to use a medicine past its expiry date or its in-use limit — the point is the opposite, that the in-use limit is usually the stricter of the two and is the one people miss. A pharmacist will tell you about your specific product, and will take back what you no longer need.