This information is relevant to people who live in the UK.
Epilepsy Action believes that you should get the same version of your epilepsy medicine, whenever possible, every time you pick up a prescription. Having the same version is known as consistency of supply.
Generic and brand names
Nearly all medicines have a generic name and a brand name. The generic name is the name of the main ingredient. The brand name is given by the company that makes the medicine.
In the first years that a medicine becomes available for patients, it is under licence. This means that only the company that researched and developed it can sell it. This company gives it a brand name.
Once the licence runs out, any drug company can make the medicine. These medicines are called by the generic name and are known as non-proprietary medicines. They may be cheaper than branded ones. Some companies who make the medicine once the original licence runs out, give it their own brand name. These are known as branded generics.
For example, with carbamazepine:
First version: The first and original version of carbamazepine has the brand name Tegretol®.
Later version: A later version made by another company has the brand name Carbagen®. This is a branded generic.
Generic versions: There are also several generic or non-proprietary versions. These all have the generic name carbamazepine and no brand name.
Whatever version of epilepsy medicine you have, the active ingredient should be identical. So, every version of carbamazepine 100mg tablets should contain 100mg of carbamazepine. However, all medicines have other ingredients as well as the main one. These other ingredients can be different, depending on who makes the medicine. For some people, this difference could affect how well the medicine works. It could also mean they experience more or different side-effects.
Prescribing by brand
If a doctor writes a brand name on your prescription, the pharmacist must give you that specific brand.
If a doctor writes the generic name of your medicine on your prescription, a pharmacist can give you that medicine from any drug company. This is called generic prescribing. There is increasing pressure on the NHS to reduce its costs in many areas. One area is prescribing costs. Because generic medicines can be cheaper than branded versions, doctors and other prescribers may want to switch some people onto those cheaper versions.
Possible issues with generic prescribing
Some people say they have no problem with taking different versions of their epilepsy medicine. However, some people who have switched to a different version of their epilepsy medicine have told us that they have had seizures after being seizure-free for some time. And some people have had more seizures and/or side-effects that they haven’t had before.
What if I can’t get the version of epilepsy medicine I usually have?
Sometimes there can be a shortage of supplies or a company may stop making a medicine. Unfortunately, where this is the case, there may be no choice but to take a different version. The health professional who usually prescribes your epilepsy medicine should be able to advise you what to do in this instance.
Advice for people who prescribe epilepsy medicine
The Medicines and Healthcare products Regulatory Agency (MHRA) is an agency of the Department of Health. In 2017 they updated their guidance on prescribing epilepsy medicines. This followed a review by the Commission on Human Medicines (CHM) which looked at the evidence on patients switching between different manufacturers’ products of particular epilepsy medicines.
CHM advise that epilepsy medicines can be classified into three categories. This classification aims to help prescribers and patients decide whether it is necessary to maintain consistency of supply of a specific company’s product. It is not official policy, but guidance only.
The MHRA’s guidelines about prescribing epilepsy medicines
It has been shown that the differences between different drug companies’ products could affect seizure control and/or side-effects. Prescribers should ensure a specific drug company’s product is always prescribed.
Whether to always have a specific drug company’s product should be based on what is right for the individual. Prescribers should talk this through with their patient and/or carer. They should look at things like seizure frequency and treatment history. They should also take into account how their patient and/or carer feels about being prescribed different versions of their epilepsy medicine.
The likelihood of there being any differences that could affect seizure control and/or side-effects between different manufacturers' products is considered to be extremely low. However, prescribers should look at each patient individually, taking into account how they and/or their carers feel about being prescribed different versions of their epilepsy medicine.
How to get the same version of your epilepsy medicine
The most reliable way to get the same version is to ask your doctor to write the brand name on your prescriptions. Or, if you want to stay on a particular manufacturer’s generic version, the doctor can write the generic name and the name of the manufacturer on your prescription. Your pharmacist should always try to give you the version your doctor has written on your prescription.
If you take an epilepsy medicine that is in category1, your prescriber should ensure you always have the same version of your medicine. If you take an epilepsy medicine in categories 2 or 3, your prescriber might want to give you a generic prescription. However, the current guidelines say that they should also take into account how you feel about having a different version.
Reporting problems with epilepsy medicines
If you think you are getting side-effects from your epilepsy medicine, or they have caused your epilepsy to change, talk to your GP. They can report these issues to the MHRA. You can also report side-effects yourself by completing a Yellow Card. These are available from your GP, pharmacist or the Yellow Card scheme:
Tel: 0800 731 6789 (10.00am – 2.00pm Monday – Friday)
If you would like to see this information with references, visit the Advice and Information references section of our website. If you are unable to access the internet, please contact our Epilepsy Action Helpline freephone on 0808 800 5050.
Epilepsy Action would like to thank Dr John Paul Leach, consultant neruologist, Southern General Hospital, Glasgow for his contribution.
Dr John Paul Leach has declared no conflict of interest.
This information has been produced under the terms of The Information Standard.
- Updated November 2017To be reviewed November 2020