Although painful and annoying, the vast majority of headaches do not indicate a serious disorder. Tension headaches and migraine headaches account for 90% of all headaches.

The different types of headaches are usually caused by one of the following:

• Muscle contraction (tension headaches)
• Vascular problems (migraine headache or cluster headache)

Some headaches are caused by a combination of these two causes.

The following characteristics indicate a headache that signals a potentially serious problem:

• Involves sudden, violent pain (could indicate an aneurysm)
• Gets worse over time and includes other symptoms
  • Speech changes
  • Visual changes
  • Personality changes
• Awakens you from sleep (could indicate a brain tumor)
• Includes nausea, vomiting, fever, and a stiff neck (could indicate meningitis)

Tension headache is a common headache pattern that may or may not be associated with psychosocial stressors. Tension headaches are characterized by the following:

• Pain usually felt in the back of the head and neck, and usually not one-sided
• Pain that lasts for weeks or months with only brief periods of relief, although it may fluctuate in severity
• Attacks that begin at any time of the day
• Pain that can be described as a "tight band," pressing, but rarely throbbing, and never accompanied by fever.

Migraine headaches, which are often preceded by fatigue, depression, and visual disturbance (light flash, loss of peripheral vision), are characterized by the following:

• Pain that is characteristically only on one side at a time, but may involve the entire head
• Pain that is throbbing in nature and usually develops in the morning and gradually becomes worse after an hour or so
• Attacks that may occur as often as every few days or weeks or as seldom as months apart. Migraines often continue for hours, but rarely last longer than a day or two.
• Pain that may be aggravated bystress, alcohol, or certain foods (such as chocolate) and is frequently accompanied by nausea and vomiting and relieved by sleep
• Having a family history of migraine headaches

Cluster headaches are a variation of migraine headaches and are far less common. They occur mostly in men, while typical migraines are more common in women. Cluster headaches are characterized by pain that:

• Is often situated behind an eye (usually the same eye)
• Comes on very suddenly and without warning
• Peaks within 5 to 10 minutes and disappears in less than an hour
• Is often triggered by alcohol
• Will awaken you from sleep and will occur several times a day for weeks and then stop

Inflamed sinuses (acute sinusitis or chronic sinusitis) are characterized by the following:

• Pain that usually begins during or after a bad cold, particularly if you have postnasal drip
• Pain that it is localized to one specific area of the face or head
• Pain that is worse in the morning, before mucus has had an opportunity to drain
• Pain that it is made worse by coughing, sneezing, or sudden movements of the head
• Pain that it is aggravated by alcohol, sudden temperature changes, and going from a warm room out into the cold (during cold seasons).
• A history of hay fever and allergies

Temporal arteritis occurs mostly in people over age 50 and is characterized by the following:

• Pain that is aggravated by chewing
• Impaired vision
• Aches and pains all over the body
• The presence of a fever
• Weight loss
• Elevated blood ESR (erythrocyte sedimentation rate)
• May progress to loss of vision

Other common causes of headaches include the following:

• Common cold
• Fever
• Hangover
• Alcohol withdrawal
• Head injury
• Neck pain from strain or arthritis
• Head or neck infection NOT involving the brain
  • Dental disease
  • Ear infection
  • Mastoiditis
  • Pharyngitis
  • Sinusitis
• Influenza
• Medications
  • Indomethacin
  • Nitrates
  • Vasodilators
• Premenstrual syndrome (PMS)
• Stress
• Tooth abscess
• Withdrawal from drugs
  • Caffeine
  • Ergotamine
  • Sympathomimetics
  • Street drugs

Rare causes include the following:

• Cerebral aneurysm
• Brain tumor
• Stroke
• TIA
• Meningitis
• Encephalitis