Many people share prescription drugs, according to a study based on interviews with 700 Americans. About 23% reported loaning their drugs to another person and 27% said they'd borrowed someone else's.

Between 21% and 25% of respondents reported borrowing or lending allergy drugs such as fexofenadine (Allegra), analgesics such as propoxyphene/acetaminophen (Darvocet) and oxycodone (OxyContin), and antibiotics such as amoxicillin. Some 7% of respondents reported sharing mood-altering drugs, such as paroxetine (Paxil) and diazepam (Valium), and 6% reported sharing the antiacne drug isotretinoin (Accutane). Five percent reported sharing oral contraceptives.

The extent of drug sharing was higher than researchers expected to find. They warn that sharing prescription medications is a risky habit and recommend more research to explore when and why patients borrow medications and what consequences they experience.

Source: Goldworthy RC, et al., Beyond abuse and exposure: Framing the impact of prescription-medication sharing, American Journal of Public Health, June 2008.