Headache is incapacitating my friend

Dear Doctor; A friend of mine suffers from debilitating headaches and he cannot work anymore. All possible tests are turning out negative - heart, Brain CT scan, etc. Worse still, one physician says ‘do this’, another says ‘don’t do it’. What could be the problem? What should we try to underpin and focus on during diagnosis? Jareth.
Ask the doctor
Ask the doctor
Times Reporter