Generic Substitution

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What’s this tablet?
A parallel import or a generic substitute? Migraine Action frequently receives letters and calls from members puzzled about apparent changes in their medicine and even reporting that the medicine they have received from the doctor and / or pharmacist looks different and does not have the same effect as their usual medication.
A huge debate has arisen around the practice both of so-called, “parallel importing” and of “generic substitution”, both of which are valid tools used by the NHS in order to control costs and manage supply. In this booklet we attempt to explain both parallel importing and generic substitution so that members have a clearer idea of why their medicines sometimes look different.

What is generic substitution?
Generic substitution occurs when a generic drug is substituted for a brand name drug with identical ingredients that has lost its patent protection. Once medicines have been discovered by pharmaceutical companies they are granted a patent which lasts for approximately fifteen years from the date the medicine is first registered as new. Registration tends to occur before the medicine is available for patients. Companies can therefore expect to have their drugs protected for as little as six or seven years when they are publicly available. Once the patent has expired medicines may be made under other names by other approved manufacturers. Generic medicines are commonplace, and are a familiar sight in pharmacies where many people will happily purchase aspirin instead of “Aspro” and paracetamol instead of “Panadol” at commensurately lower costs. One migraine treatment which can be available both in branded and generic forms is Imigran which is also prescribed and dispensed generically as sumatriptan - the name of its active ingredient.

Doctors choose whether to prescribe a generic or branded drug where both are available. Their choice is influenced by the health authority which will have a list detailing those medicines which doctors should consider prescribing generally. Pharmacists are required to dispense the medicine shown on the prescription so if a generic has been prescribed that will be dispensed. Currently the Department of Health is seeking to widen the use of generic medicines and is consulting widely with a view to permitting pharmacists to substitute certain branded medicines written by a GP on a prescription with the equivalent generic. The consultation is in its early phase but certainly we must all accept that the principle of generic substitution and the use of generics is likely to expand rather than contract.  Please note that you should always report any side effects either to your GP or Pharmacist.

While many generics are identical in composition to the branded equivalent a few may vary in their make up - these changes of course have to be with the agreement of the regulatory authorities. It is these small modifications which occasionally lead to people feeling that their medicine isn’t working in the way they expect.

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