Call to rethink drug expiry dates

Medicines often retain full potency for decades after their expiry dates, a study finds, prompting calls to rethink the “arbitrary” process for setting use-by dates.

The analysis of eight medicines, which were 28-40 years out of date, found almost all contained their active ingredients at concentrations of at least 90% of the labelled amount.

Twelve of the 14 active ingredients, ranging from codeine to chlorpheniramine, exceeded this percentage, which is generally recognised as the