The Department of Health has informed prescribers of the forthcoming patent expiry of GSK's Lamictal reassuring them that generic versions will be just as good as the original version.

GPs and healthcare professionals have been notified that switching patients to generic versions of lamotrigine will pose no adverse clinical risk and will mean huge savings for PCTs.

The DH issued a note in recent weeks saying: "The MHRA will ensure that bioequivalence is established between the brand Lamictal and potential generic alternatives."

£55 million was spent on the drug in England in 2004, making it the second-biggest selling epilepsy drug, close behind Pfizer's Neurontin, which also recently went off patent in the UK.

The memo is careful to stress that the clinical judgment of the prescriber would be the deciding factor, based on the needs of individual patients, but made it clear there should be no other factors influencing the decision.

"Some commentators have suggested that there should be no switching of products used in the treatment of epilepsy," it continued, "but in this instance, there is no compelling evidence to suggest that switching from the originating brand to a generic alternative will have an adverse clinical outcome.

Patient group The National Society for Epilepsy said there were potential problems when switching to generic versions of many epilepsy drugs but that lamotrigine was not such a case.

Professor John Duncan, medical director at the society said: "With regard to lamotrigine, it does not appear likely that there will be significant differences in the bioavailablity of the drug from generic formulations."

A spokesperson for GlaxoSmithKline said the company agreed with the department's advice, recommending that healthcare professionals make individual assessments of the needs of their patients.

The move is designed to encourage take-up of generic alternatives and is a demonstration of the government's renewed determination to get the best value for money from its prescribing budgets.

In an unrelated case, the generic firm Ranbaxy recently agreed to settle out of court with the government by paying £4.5 million in relation to a price fixing case brought by the Department of Health.

The company agreed to settle without admission of liability. The Department is claiming losses of £150 million against a number of other generic manufacturers in an on-going court case.

pharmafocus@wiley.co.uk