My medicine: Changes in the use of a medicine

 

The more widely a medicine is prescribed, the more becomes known about its effects, and a change in use may be required.

This is because:

• New scope for treatment or increasing confidence in the safety record of an effective medicine can prompt it to be used more widely
• Concerns about the safety or quality of a medicine can prompt the regulator to restrict its use or change its status

Changes are usually requested by the manufacturer, but sometimes healthcare professionals or the regulator will ask for them.

Reports to the Yellow Card Scheme or research carried out using the information supplied to the General Practice Research Database (external link) can pinpoint patterns in the use of a medicine, which may affect how, and to whom, it is prescribed.

What changes can be made?
Changes can include:

• The addition of different conditions or age groups for which the medicine can now be prescribed
• Restrictions to the dose, length, or frequency of treatment as a result of unexpected side effects coming to light
• Limits on the quantity available—for example, paracetamol containers are now limited to 16 tablets in supermarkets and 32 in pharmacies, to cut the risk of serious liver damage when taken in large amounts
• A switch in legal status―from prescription only medicine (POM) to over the counter use under the direction of a pharmacist (P). Sumatriptan (50 mg tablets), for the relief of migraine symptoms, is now P status, for example
• Sometimes a medicine will be switched from P to GSL (General Sales List), which means it can be bought at a supermarket or corner shop, to boost its availability. Nicotine replacement lozenges are one such example
• Rarely, withdrawal of a medicine from sale because of serious safety concerns

Switching the legal status of a medicine
The legal status of a medicine will be changed only if the regulator is completely satisfied with its safety record, and after healthcare professionals and the public have been widely consulted.

Healthcare professionals are quickly advised of any changes in the use of a medicine by the manufacturer and the regulator, and these changes are then added to:

• Product information
• Patient information leaflets
• Prescribing reference manuals for healthcare professionals

Withdrawing a medicine
Before deciding to withdraw a medicine from sale, or restrict its use, the regulator carefully assesses all the available evidence for and against. This includes the impact its decision will have on patients who respond well to the medicine.

Independent expert advice is sought, and where appropriate, the public is also consulted. Decisions are based on the need for openness and honesty, and must be backed up by sound evidence and reasoning.

The pain-killer co-proxamol was withdrawn in 2005, for example, after earlier research had shown that it was involved in almost a fifth of all drug related suicides.

Most medicines work well and are acceptably safe. And the licensing process is so rigorous that few medicines are taken off the market because of safety concerns. Only 20 medicines have been withdrawn in the past 10 years from the 30 000 or more medicines licensed in the UK.

Reporting side effects and symptoms (Yellow Card Scheme)
Healthcare professionals and now patients can report as yet unidentified side effects and symptoms they suspect may be associated with a particular medicine or herbal remedy to the Yellow Card Scheme.

This is a confidential reporting system run by the Medicines and Healthcare products Regulatory Agency (MHRA), which aims to help build up a broader picture of how a medicine is working.

It provides invaluable feedback and enables the MHRA to pick up any problems that may be associated with taking a medicine and to take swift corrective action, if required.

And it can make a real difference. For example, in 2003, patients taking the blood thinning drug warfarin were advised not to drink cranberry juice, after it was found that the combination of the two boosted the risk of internal bleeding (haemorrhage).

Reports, including those on behalf of a child or adult in a person’s care, can be made by:

• Filling in a yellow card, available from GP surgeries or local pharmacies
• Completing a form online available in our Reporting suspected adverse drug reactions section.
• Calling 0808 100 3352.

Remember, a symptom that occurs while taking a medicine does not necessarily mean that it has been caused by that medicine. But it is always worth reporting it to the Scheme, none the less, in case it is part of a wider pattern and needs further investigation.