Dear Doctors: I am experiencing extreme headaches about 15 minutes after smoking cannabis. It used to happen occasionally, but now it’s every time. The migraine, which is very intense, goes away after about 30 minutes. Can you help me understand this?
Dear Reader: Colleagues who are experts in the area of headache and migraine pointed us to a phenomenon known as reversible cerebral vasoconstriction syndrome, or RCVS, which causes the symptoms you have described. Primary among them is the sudden onset of a severe and debilitating headache.
