There are some forms of hair loss that need a prompt referral to a dermatologist (a medically qualified skin specialist) who can arrange more in depth tests and is able to prescribe medications for some permanent hair loss conditions.
Dermatologists are doctors who will have undergone extensive training after obtaining their medical degree. The majority work in the NHS, but there can be some long waiting times for dermatology out patient appointments in the NHS. There are a few dermatologists who run hair loss clinics in the private sector.
Not all GPs will necessarily be aware of the need to promptly refer to a dermatologist for some hair loss conditions that are potentially permanent. –