Thank you for the question.
The expiration date is the final day that the manufacturer guarantees the full potency and safety of a medication. The problem with an expired drug can be:
1. A reduced content of the active ingredient: This usually is not an issue, for example in the case of an analgesic or a multivitamin. However, it becomes a problem in the case of drugs like antibiotics (plasma concentration below MIC - leading to resistance) or hormones (thyroxine, OCPs, etc) or drugs like digoxin or antiarrhythmics.
2. Formation/generation of toxic metabolites: though this list is small, it is important in case of drugs like tetracyclines that are still widely used in under-developed countries due to their low cost.
It is better to not use those drugs. It might lead you to severe problems. I hope this will help you. Take care.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.