Headache: Types, Causes and Warning Signs

Types of headaches

Tension-type headache

Tension-type headache is the most common type. It feels like a tight band or pressure around the forehead, temples or back of the head, on both sides. Pain is mild to moderate, does not throb, and is not made worse by routine activity. There is no vomiting. Stress, poor sleep, eye strain, missed meals and neck tension are common triggers. Episodes last 30 minutes to several days.

Migraine

Migraine causes moderate to severe throbbing pain, often on one side, lasting 4 to 72 hours. It is made worse by movement and usually comes with nausea, vomiting, and sensitivity to light and sound. About 1 in 4 people with migraine have an aura: visual zigzags, flashing lights or tingling that spread over 5 to 60 minutes before the pain. Migraine is about three times more common in women and often runs in families.

Cluster headache

Cluster headache causes excruciating, stabbing pain around or behind one eye, lasting 15 minutes to 3 hours, with a watery red eye, a blocked or runny nostril and a drooping eyelid on the same side. People feel restless and pace. Attacks happen up to several times a day, often at the same time, in "clusters" lasting weeks.

Medication overuse headache

Taking pain relievers on too many days, for example simple analgesics on 15 or more days a month, or triptans, combination painkillers or opioids on 10 or more days, can cause a daily or near-daily headache. See medication overuse headache. It improves after stopping or reducing the overused medicine, usually with a doctor's support.

Headache location: what it can mean

Location is a guide only. Migraine, for example, can be on both sides or at the back.

Secondary headache causes

Common and usually harmless

• Colds, flu and fever.
• Dehydration, missed meals and hangovers.
• Caffeine withdrawal: a headache 12 to 24 hours after missing your usual coffee.
• Sinusitis: facial pressure, a blocked nose and thick discharge. Many "sinus headaches" are actually migraines.
• Eye strain and uncorrected vision.
• Teeth grinding and jaw (TMJ) problems.
• Sleep problems, including sleep apnea (morning headaches).
• Hormonal changes: periods, the pill, pregnancy and menopause.

Serious causes not to miss

• Subarachnoid hemorrhage: bleeding around the brain, usually from a burst aneurysm. A sudden, explosive headache, often described as the worst ever, sometimes with vomiting, neck stiffness or collapse.
• Meningitis: headache, fever, stiff neck, light sensitivity, and sometimes a rash.
• Giant cell arteritis: a new headache over 50 with tender temples, jaw pain on chewing and vision problems. Untreated, it can cause sudden blindness.
• Stroke and brain tumors: headache with neurological symptoms. Brain tumors rarely cause headache alone.
• Very high blood pressure: blood pressure has to be very high (typically above 180/120) to cause headaches, usually with other symptoms.
• Carbon monoxide poisoning: headaches in several people in the same building, better away from home.
• Acute angle-closure glaucoma: headache with a painful red eye and blurred vision.
• Preeclampsia: a headache in the second half of pregnancy with swelling or vision changes.

When to worry about a headache

Doctors use red flags to decide who needs urgent tests. Most headaches have none. Get help urgently for:

• sudden onset, peaking within a minute
• fever, stiff neck or rash
• weakness, numbness, speech problems, confusion, seizure or vision loss
• headache after head injury
• a new headache after age 50
• headache worse when lying down, or triggered by coughing, sneezing or straining
• headache in someone with cancer, HIV or on immunosuppressants
• a steadily worsening headache over days or weeks

How headaches are diagnosed

Diagnosis is mostly based on the history: when the headaches started, how often, how long they last, where, what they feel like, other symptoms, triggers, medicines and family history. A headache diary over a few weeks is very helpful. A neurological examination and blood pressure check follow. Scans (CT or MRI) are only needed when red flags are present or the pattern is unusual. A lumbar puncture may be done for suspected meningitis or bleeding.

Headache relief and treatment

For an individual headache

• Over-the-counter pain relievers: acetaminophen (paracetamol), ibuprofen, naproxen or aspirin at the label dose, taken early. Do not give aspirin to children or teenagers. Avoid NSAIDs if you have stomach ulcers or kidney disease.
• Limit use to no more than 2 to 3 days a week to avoid medication overuse headache.
• Rest in a dark, quiet room for migraine, with a cold pack on the forehead.
• Fluids and a light meal if dehydration or missed meals are triggers.

Migraine-specific treatment

Triptans, gepants and ditans treat migraine attacks. Anti-sickness medicines help nausea. For frequent migraines, preventive treatment is offered, such as certain blood pressure medicines, antidepressants, anti-seizure medicines, CGRP monoclonal antibodies, or Botox injections for chronic migraine.

Cluster headache treatment

High-flow oxygen through a mask and injected or nasal triptans treat attacks. Verapamil and other medicines prevent clusters.

Prevention and lifestyle

• keep regular sleep, meals and caffeine intake
• drink enough water
• exercise regularly
• manage stress with relaxation, CBT or biofeedback
• correct vision problems and take breaks from screens
• track and avoid personal triggers

Frequently asked questions

When should I worry about a headache?

Worry if a headache is sudden and severe, comes with fever and stiff neck, weakness, confusion, vision loss or seizure, follows a head injury, or is a new type after age 50. These need emergency or urgent care. Most familiar headaches are not dangerous.

What are the main types of headaches?

The main types are tension-type headache, migraine, cluster headache and medication overuse headache. Secondary headaches result from other conditions, such as infections, sinus problems, high blood pressure, head injury or, rarely, bleeding in the brain.

Why do I get headaches every day?

Daily headaches are most often chronic tension-type headache, chronic migraine or medication overuse headache from frequent pain reliever use. Poor sleep, sleep apnea, caffeine, stress and jaw clenching can contribute. See a doctor for an assessment and a prevention plan.

What does a headache at the back of the head mean?

Headaches at the back of the head are usually tension-type headaches or come from the neck muscles and joints. Migraine can also be felt there. A sudden severe headache at the back of the head needs emergency assessment for bleeding.

Can dehydration cause headaches?

Yes. Dehydration is a common headache trigger. Drinking water often eases it within 30 minutes to 3 hours. Regular fluid intake helps prevent dehydration headaches, especially in hot weather or after exercise or alcohol.

Is a migraine just a bad headache?

No. Migraine is a neurological condition with recurrent attacks of moderate to severe headache, often with nausea, light and sound sensitivity, and sometimes aura. It can be disabling and has specific treatments that ordinary headache relief does not provide.