it is difficult to say if the unused medications are expired or surplus unless they are returned in original packed mentioning the expiry date. In many countries like canada pharmacies do not dispense medication in original package material but dispense them in vials on which the expiry date is not mentioned and as per pharmacy regulations there the returned medication has to be disposed off and cannot be reused.

It is obvious that check expiry date before administration of any drug

If date is not visible then discard

What is your query?

This is a questionable situation. Medicines are kept under rigorous temperature and humidity conditions in pharmacies and in warehouses. If a patient returns them, do we have the certainty that it has kept them in optimal conditions in order to have the maximum safety when we reuse them in another patient? In other words, there may be drugs that are necessarily needed at some point. And then, we could select the pharmaceutical forms with intact packaging, which are stored at temperatures between 18-25 degrees Celsius, in conditions closer to those at the patient's home that returned them.

yes expiry date of medicine is must to check and it is good not to use such medicines as we do not know about the condition in which they were kept.

I have long believed that expiration dates are based on selling more new product when the product expires rather than on actual expiry of the product. There is zero incentive for companies to prove their product is good for 15 or 20years; when they can ensure repeated sales even with a 'long' expiry of 5 years. Most drugs have much shorter than 5 years. I have long held the belief that although medications may be expired acording to US standards, the medication would be much appreciated in a third world country.

That said, Multiple goverment studies in US, within last 60 years, have checked expiry of stockpiled meds and found drugs well within the original 90% original potency. Within 10% of originial potency being the basis for most expiry policy. (there is also dissolution and absorption and adsorption issues, but these are generally in line with the rest of the characterisitc of the finished product and therefore, generally in good shape along with the potency of the product.)

Most recent study of this type was actually NOT a government study but a very illuminating read. Here is the internet reference:

https://www.propublica.org/article/the-myth-of-drug-expiration-dates from July 18, 2017. The MYTH of Drug Expiration Dates.

Fatima it is good question.

I am dealing with lots of international patients and give 6 month or more medicines to them.

Patient counseling is most important part at the time of dispensing. Minimum 2 patient's relative must counsel about medications.

Second point is expiry. Expiry must see in all the strip. At the time of packing, expiry wise packing done.

Does the expired drugs not work, or it is not safe to be used ie, it became toxic.

Actually during the period of economic sanction we used expired drugs, though few months after the fixed date, it was working well.