If a medicine is not on a General Practitioner (GP) formulary in the UK, it means that the medicine is not included in the list of medications that are commonly prescribed or recommended by GPs in that particular area or healthcare setting. The formulary is usually developed based on a combination of factors such as clinical effectiveness, safety, and cost-effectiveness.

When a GP does not want to prescribe a medicine that is not on the formulary, it could be due to several reasons:

1. Clinical Guidelines: The medicine may not align with current clinical guidelines or best practices for treating the condition in question.
2. Safety and Efficacy Concerns: The GP may have concerns about the safety or efficacy of the medication, especially if it has not been widely studied or used.
3. Cost-Effectiveness: Medications not on the formulary might be more expensive and less cost-effective compared to other available alternatives that are on the formulary.
4. Personal Judgement: Sometimes, it’s a matter of the GP’s professional judgment and experience. They might not feel comfortable prescribing a medication they are not familiar with or do not consider the best option for the member’s specific situation.
5. Regulatory Restrictions: There could be regulatory restrictions on prescribing certain medications, especially if they are not approved for use by the relevant health authorities or for the specific condition being treated.
6. Unlicensed Medication: Sometimes a medication might not be on the formulary because it is unlicensed for the condition being treated. Unlicensed medications are those that have not received approval from health authorities (like the Medicines and Healthcare products Regulatory Agency in the UK) for specific uses. While doctors can prescribe unlicensed medications under certain circumstances (off-label use), they often do so with caution. The lack of licensing could be due to insufficient evidence about the drug’s efficacy or safety for the particular condition, or because the drug has never been officially assessed and approved for that specific use. This makes some doctors hesitant to prescribe unlicensed medications, as they have to take full responsibility for any risks associated with their use.

It’s important to have an open discussion with your doctor about your treatment options and to ask them about alternatives that are on their formulary.