You can register as a temporary resident with a GP if you are in the area for longer than 24 hours but less than three months. You'll still remain registered with your permanent GP, but you can see your temporary GP for up to three months after which your temporary registration will expire.  

You can register temporarily with a GP near where you're staying if you're ill or need medical advice while you're away from home – for example, if you're working, studying or on holiday. Your temporary GP will pass details of any treatment you have to your permanent GP, who will then add the information to your medical records.