A medicine is said to be expired when the potency of the active drug (Active Pharmaceutical Ingredient) present in the medicine is reduced to 90% i.e. the active drug is 10% degraded. For example if a tablet containing 100 mg/tablet of X drug is manufactured today and its expiry date is Aug 2020 means that in around Aug 2020 the active drug X present in that tablet will be 90 mg/tablet and 10 mg/tablet will be degraded products which can be harmful. It is not safe to take expired medicine as it may be non effective, less effective, non potent or sometimes toxic. The expiry date can be reached earlier than claimed on label if the medicine is not stored properly as mentioned on label of that medicine especially when it is to be stored in refrigerator. In case expired medicine is consumed manufacturer cannot be held responsible for any side effect or toxic reaction revealed after consumption of expired medicine. One should be very cautious of expiry date especially for injections.
