My son uses minoxidil, the tablets. He previously tried the topical solution which was messy and a faff.
I'm not sure it makes hair grow back that has already been lost but it seems to be preventing further loss, and he feels it is worth it for him.
GPs will not prescribe, it isn't funded by NHS, but can be bought online including the prescription from a number of UK sites. No need to waste money on expensive dermatology consultations if you want to try it.