Hello! Thank you for asking on HCM! I read your question carefully and understand your concern. His past history of cocaine intake is really concerning. I would like to explain that cocaine intake is related to different complications (such as high blood pressure, brain vessel disorders ),which cause headache. Have you measured his blood pressure? I recommend consulting with the GP as soon as possible for a careful physical examination, a routine blood test, inflammation tests (fibrinogen, PCR, sedimentation), blood electrolytes, kidney and liver function tests. It is important to closely monitor his blood pressure. A transcranial Doppler ultrasound of the brain vessels and a brain MRI may be needed to exclude the above disorders. Hope to have been helpful! Best wishes, Dr. Aida