They do not appear to be related to social class, occupation, etc., and thus can occur in virtually anyone at anytime. Attacks are intermittent, lasting from a few hours to as long as a day or more. Nausea, vomiting, loss of appetite, fatigue, and sensitivity to sound and light frequently accompany the headache. Biochemical imbalances, fluctuations in cranial blood flow, and certain neurological events are thought to underlie migraine. Cluster headache is another type of vascular headache, so named because attacks come in bouts of frequent, but short duration headaches, then go away for extended periods of time.
Cluster headache is rare and is the only type to be more common in males than females.
Tension, or muscle contraction, headache is believed to result from excessive contraction of muscles in the shoulders, neck, and head. These contractures affect oxygen and nutrient intake to the muscles and impinge on pain sensitive structures, both of which contribute to the experience of pain. Recently it has been suggested that some cases of tension headache may actually be variants of vascular headache. It is not unusual for this type of headache to be a daily occurrence. Headaches can be an indication of a serious underlying organic problem, so it is always wise for individuals to have their symptoms evaluated by a medical specialist.