Patients with chronic illness frequently consume unnecessary amounts of medicine. In some instances, the side-effects or toxic effects produced by overmedication, due to the duplication of prescriptions given the patient, are more serious than the complaint for which he was being treated originally. Patients disabled for long periods by chronic illness tend to consult many physicians, with the meetings often occurring without the knowledge of the first doctor in attendance. Some patients remain silent when confronted with the question of who referred them, since they assume "their doctor" would feel insulted if he were to learn that additional medical advice had been sought. As a result, patients often ingest a large variety of medicaments, and no one single physician is fully cognizant of the entire therapeutic program.
Meyer1 points out that, unless patients are otherwise instructed, they are, often as not, likely to consume both old and newly prescribed
THERAPEUTIC DUPLICATION. JAMA. 1956;160(9):780. doi:10.1001/jama.1956.02960440052016