Generic prescribing for epilepsy. Is it safe?

Generic prescribing for epilepsy remains controversial. This study aimed to ascertain if a change occurred in the incidence of seizures or side-effects when a different pharmaceutical manufacturer's version of the same antiepileptic drug was taken (a 'switch'). Forty general practices with a list size of 350 168 were recruited. They identified 2285 people being treated for epilepsy with either carbamazepine, phenytoin or sodium valproate. A questionnaire was sent to the people with epilepsy. Those who recalled taking a different pharmaceutical manufacturer's supply of the same antiepileptic drug over the last 2 years were interviewed by their practice if they reported a problem with the control of their epilepsy after a 'switch'. One thousand, three hundred and thirty-three (58.8%) people with epilepsy responded: 251 (18.7%) had experienced a 'switch', 27 (10.8%) reported 'validated' problems; 25 (9.9%) reported unproven problems; 22 (8.8%) reported problems, but follow-up was incomplete; 177 (70.5%) reported no problems. This study suggests that money saved by generic prescribing is outweighed by negative health gain for the person with epilepsy, increased work in general practice, and increased social costs.