Headache

A headache can be described as a pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions. The brain tissue within the skull itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the pain-sensitive structures around the brain.

In the context of substance usage, the overuse of certain substances can cause painful headaches, particularly during the offset of the experience and if the user is dehydrated.

See also

• Subjective effects index
• Psychedelics - Subjective effects
• Dissociatives - Subjective effects
• Deliriants - Subjective effects