Answer
Check the destination country's rules and carry proof that it was prescribed for you. Controlled-drug medicines should be carried personally, normally in hand luggage when entering or leaving the UK.
Sources for this answer
- UK GovernmentUK Government · Reputable Web
- UK GovernmentUK Government · Reputable Web
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.