The impact of generic labels on the consumption of and adherence to medication: a randomized controlled trial

Although generic drugs are pharmacologically equivalent to their brand-name counterparts, prejudices against them remain strong. We assess the extent to which generic (versus brand-name) labels affect patients' consumption of and adherence to medication.

One hundred one patients who received dental implants agreed to participate in a study. In a pre-surgery survey, most patients reported a positive view about generic drugs. After dental surgery, the patients were prescribed a once-daily analgesic regimen (50 mg tramadol hydrochloride) for up to 7 days. All the patients received at no cost the same brand-name medication with either a brand-name label (n = 51) or a generic label (n = 50) and were informed of the retail prices associated with both labels. Telephone follow-up was conducted 24 hours, four days, and seven days after surgery to assess the number of prescribed pills consumed and when their use was discontinued, the number of non-prescribed pills consumed, pain levels throughout the follow-up period, the perceived efficacy of the analgesic, and the willingness to recommend it to a friend.

The label manipulation impacted the participants' behaviour and subjective assessments. Discontinuation before the end of the 7-day period was more frequent under the generic (vs. brand-name) label condition. The patients in the generic label group were also more likely to consume non-prescribed pills (non-adherence). Additionally, the patients in the generic label group reported higher levels of pain.

Generic labels may negatively affect adherence to treatment even if patients report ex ante positive evaluations of the quality of generics drugs.