Overview

A headache is pain or discomfort in the head, scalp, face, or neck. Many headaches are temporary and related to everyday factors such as stress, sleep changes, illness, dehydration, or skipped meals. Some headaches are more complex, especially when they are new, severe, recurring, or paired with other symptoms.

This article explains common reasons headaches happen and signs that a headache should be discussed with a healthcare professional. It is educational and cannot identify the cause of a specific headache or guide urgent decisions.

Common causes

Tension-type headache is a common pattern. It may feel like pressure or tightness around the head, scalp, neck, or shoulders. Stress, anxiety, depression, long periods at a desk, poor sleep, or muscle tension may contribute.

Migraine is another common headache disorder. Migraine can cause moderate to severe head pain and may occur with light sensitivity, sound sensitivity, nausea, or visual symptoms in some people. A clinician can help decide whether symptoms fit migraine or another condition.

Illness can also trigger headache. Colds, flu, other viral illnesses, fever, sinus symptoms, or dehydration during illness may all be involved. A headache with fever, stiff neck, confusion, or worsening symptoms needs prompt medical advice.

Missed meals and sleep changes are frequent contributors. Skipping food, delaying meals, sleeping much less or much more than usual, jet lag, or changes in routine can make some people more likely to have headaches.

Stress and dehydration can add to headache risk. Emotional stress, physical overexertion, heat exposure, and not drinking enough fluids may all play a role. Alcohol can also trigger headaches for some people, either soon after drinking or the next day.

Medication factors matter. Some medicines can cause headache as a side effect. Frequent use of pain relievers can also lead to headaches that keep coming back in some people. Do not stop a prescribed medicine without talking with a clinician.

When to seek medical help

Consider contacting a healthcare professional if headaches are new for you, happen often, are getting worse, wake you from sleep, last more than a few days, interfere with work or daily life, or change in pattern. It is also reasonable to ask for care if over-the-counter pain relievers are needed often, no longer help, or cause side effects.

People who are pregnant or could be pregnant, have a weakened immune system, have cancer, have a recent head injury, or are older than 50 with new headaches should seek medical advice promptly.

Emergency warning signs

Call emergency services or go to an emergency department if a headache is sudden and severe, feels like the worst headache of your life, starts after a head injury, or occurs with fainting, confusion, seizure, stiff neck, fever, repeated vomiting, trouble speaking, weakness, vision changes, loss of balance, or trouble moving an arm or leg. Ear pain after an injury should also be checked urgently.

Emergency care is also important for a severe headache with red eye or eye pain, a headache that quickly worsens over hours, or a headache with chest pain, severe trouble breathing, or other symptoms that feel urgent.

What a clinician may check

A clinician may ask when the headache started, where the pain is, how it feels, what makes it better or worse, and whether there are symptoms such as fever, nausea, vision changes, weakness, dizziness, or sensitivity to light. They may review sleep, meals, hydration, alcohol use, stress, medical history, and current medicines.

Depending on the situation, the visit may include a physical exam, neurological exam, blood pressure check, medication review, or tests. Imaging is not needed for every headache, but it may be considered when warning signs or certain risk factors are present.

Self-care boundaries

General steps such as resting, drinking fluids, eating regular meals, limiting alcohol, improving sleep habits, and using relaxation strategies may help some people reduce headache triggers. A headache diary can also help track patterns to discuss with a clinician.

These steps are not a diagnosis or a treatment plan. Frequent, severe, changing, injury-related, or symptom-linked headaches should be checked. Ask a clinician or pharmacist before using pain relievers frequently, combining medicines, or using medicines during pregnancy or for a child.

FAQ

How can I tell whether a headache is common or serious?

There is no single feature that proves a headache is harmless. A mild headache that matches a familiar pattern may be less concerning, but a sudden severe headache, a new pattern, neurological symptoms, fever with stiff neck, head injury, or worsening symptoms should be evaluated quickly.

Can dehydration cause a headache?

Yes. Dehydration can contribute to headaches, especially with heat, illness, alcohol use, vomiting, diarrhea, or heavy sweating. Severe dehydration symptoms, such as confusion, fainting, or very little urination, need urgent medical attention.

Can pain relievers cause more headaches?

They can in some situations. Using headache pain relievers too often may contribute to rebound or medication-overuse headaches. If you need pain relievers frequently, ask a healthcare professional how to use them safely and whether the headache pattern needs evaluation.

Sources

The sources listed for this article include MedlinePlus pages on headache, headache danger signs, and tension headache.

Medical disclaimer

This content is for educational information only and does not replace professional medical diagnosis, treatment, emergency care, or advice from a qualified clinician.