01 · Overview
The short version
Location alone does not tell you the cause
Pain on one side, behind the eyes, or in the back of the head can happen with different headache types. Timing, triggers, and other symptoms matter more than location by itself.
Some headaches need urgent attention
A sudden severe headache, headache after a head injury, or headache with confusion, fainting, weakness, trouble speaking, seizure, fever, stiff neck, or vision loss should be treated as urgent.
Caffeine can help or hurt
Too much caffeine can cause headaches, and suddenly stopping regular caffeine can cause withdrawal headaches. Energy drinks, coffee, tea, soda, and some medicines can all add up.
Frequent headaches deserve a pattern check
If headaches keep coming back, a diary can show links to sleep, meals, stress, hydration, caffeine, and pain medicine use. That record helps a clinician look for a cause and a safer plan.
02 · Care guidance
When to get help
Emergency help
- Call 911 or local emergency services now if a headache starts suddenly and is severe, happens after a head injury, or comes with confusion, fainting, weakness, trouble speaking, seizure, chest pain, or loss of vision.
Get advice promptly
- Contact a clinician soon if you are having new headaches, headaches that are happening more often, headaches that wake you from sleep, headaches with nausea or light sensitivity, or headaches that are interfering with daily life.
- Get urgent same-day care if a headache comes with fever and stiff neck, eye pain, new neurologic symptoms, pregnancy-related high blood pressure symptoms, or signs of dehydration or infection.
If your headaches are mild and familiar, start with a symptom log that includes timing, location, severity, sleep, meals, caffeine, stress, and medicines used. Bring that pattern to a primary care clinician or neurologist if the headaches keep coming back.
03 · Headaches
What the headache pattern is trying to tell you
A headache is a symptom, not a diagnosis.
A headache is pain in the head or face, but that pain can come from several different causes. The most common types are tension headaches and migraines, yet headaches can also happen with sinus problems, dehydration, poor sleep, eye strain, infections, medication side effects, caffeine changes, or other illnesses.
The pattern is usually more useful than the exact spot of pain. A dull, tight feeling may fit tension headache, while throbbing pain with nausea or light sensitivity points more toward migraine. A headache that is brand new, unusually severe, or different from your usual headaches deserves more attention than one that feels familiar.
- Write down when it started and how long it lasts.
- Notice whether the pain is tight, dull, throbbing, or stabbing.
- Track nausea, light sensitivity, fever, and vision changes.
04 · Headaches
When tight muscles and stress are the main clue
Tension headaches are often tied to stress and muscle tension.
Tension headaches are the most common type of headache. They often feel like pressure or tightness instead of a pounding pulse. Some people feel it across the forehead, in the temples, or as soreness in the neck, scalp, shoulders, or jaw.
Stress, anxiety, depression, lack of sleep, missed meals, and alcohol can make these headaches more likely. That does not mean the headache is 'all in your head.' It means the body is reacting to strain in ways that can be very real and very painful.
The practical question is whether your routine is feeding the pattern. A headache that follows long workdays, skipped meals, poor sleep, or clenched jaw muscles may improve when those pieces are addressed. If the headaches are happening often, a symptom log helps show whether there is a repeatable trigger.
- Keep sleep times as steady as you can.
- Do not skip meals if that seems to set off headaches.
- Notice neck, shoulder, and jaw tension during stressful periods.
05 · Headaches
When migraine fits better than a simple tension headache
Migraine often comes with other symptoms, not just pain.
Migraine is a recurring type of headache that often causes moderate to severe throbbing or pulsing pain, commonly on one side of the head. It may come with nausea, vomiting, and sensitivity to light, sound, or odors. Some people also have aura, such as flashing lights or zig-zag lines, before or during the headache.
A migraine can sometimes be mistaken for a one-sided tension headache, sinus pressure, or another type of pain. One-sided pain alone does not prove migraine, but the overall pattern matters. Repeated headaches with nausea, light sensitivity, and worsening with movement are more suggestive of migraine than a simple tight-band headache.
New, one-sided, or persistent weakness should not be brushed off as a routine migraine symptom. That needs urgent evaluation because weakness can also signal a serious neurologic problem. Migraine can have many symptoms, but new weakness is not something to diagnose at home.
- Look for throbbing pain, not just pressure.
- Pay attention to nausea, vomiting, and light or sound sensitivity.
- Do not assume new weakness is part of migraine.
06 · Headaches
Daily habits that can set headaches off
Small routine changes can matter for many headaches.
Headaches often show up when more than one thing changes at once. Skipped meals, too little sleep, stress, dehydration, alcohol, bright lights, loud noise, strong smells, and too much physical exertion can all play a part. Some people also notice headaches around hormonal changes or weather changes.
Caffeine deserves special attention because both too much caffeine and caffeine withdrawal can cause headaches. Caffeine is in coffee, tea, soda, energy drinks, and some medicines. If your intake goes up and down from day to day, that swing itself can be part of the problem.
A headache diary is useful because memory tends to miss patterns. Writing down sleep, meals, fluids, caffeine, stress, and pain medicine use makes it easier to see what repeats before the pain starts.
- Keep caffeine intake steady if withdrawal headaches are a problem.
- Watch for hidden caffeine in pain relievers and cold medicines.
- Record sleep, meals, fluids, and stress on headache days.
07 · Headaches
When pain medicine helps, and when it starts to backfire
Some headache medicines can help, but frequent use can become part of the problem.
Over-the-counter pain relievers can help some headaches, and migraine medicines may work best when taken early in an attack. The best choice depends on the headache type, your other health conditions, and the medicines or supplements you already use.
The caution is that frequent use of pain medicine can sometimes lead to more headaches. The source material lists medication overuse as a migraine trigger, which means the medicine pattern itself can keep the headache cycle going. That is one reason a clinician may ask exactly how often you take pain medicine.
Caffeine may be hidden in some headache, cold, alertness, and energy products. That matters because you may be taking more caffeine than you realize, which can either trigger headaches or make withdrawal more likely if you skip a dose.
- Check labels for hidden caffeine.
- Avoid frequent pain-medicine use without clinical guidance.
- Bring a full medicine list, including supplements.
08 · Headaches
Which headache changes need faster medical attention
Certain headache features are red flags.
Some headaches should be evaluated right away because they can signal a more serious problem. Sudden, severe headache is one of the biggest red flags, especially if it is the worst headache you have had or it started after a blow to the head.
Headache with fever, stiff neck, confusion, loss of consciousness, eye pain, ear pain, weakness, trouble speaking, seizure, or vision loss needs urgent medical attention. These symptoms are not the kind to watch and wait at home.
Headaches that are getting steadily worse, happening daily, or waking you from sleep are also worth prompt medical review. In pregnancy, headache plus blood pressure symptoms or vision changes needs special attention because the concern level is higher.
- Do not wait at home for a sudden worst-ever headache.
- Headache after injury should be assessed promptly.
- Pregnancy plus headache and vision or blood pressure symptoms needs urgent care.
09 · FAQ
Questions people ask
Why does my headache keep waking me up?
Headaches that wake you from sleep should be checked because the timing can matter. They can happen with migraine, but they can also point to another problem that needs evaluation. If the headaches are new, getting more frequent, or paired with vomiting, vision changes, or neurologic symptoms, contact a clinician soon rather than assuming it is just poor sleep.
Can dehydration cause headaches?
Yes, dehydration can contribute to headaches, especially when it happens along with missed meals, heat, exercise, or too much caffeine. Drinking fluids may help some mild headaches, but if headaches keep happening, there is usually more than one factor to look at. If you also have fever, vomiting, or signs of infection, get medical advice sooner.
What should I write down in a headache diary?
Track when the headache starts, how long it lasts, where the pain is, how severe it feels, and whether it is dull, tight, throbbing, or stabbing. Add sleep, meals, caffeine, stress, fluids, medicines taken, and any nausea, light sensitivity, or vision changes. A diary helps a clinician spot patterns that are hard to remember later.
Do I need imaging or tests for every headache?
No. Many headaches are diagnosed from the story and exam, not from scans. Testing is more likely when the headache is sudden, severe, unusual, or paired with red-flag symptoms such as weakness, confusion, fever and stiff neck, or vision loss. A clinician decides what is needed after hearing the full pattern.
Are sinus headaches real?
Headache can happen with sinus problems, but not every headache with pressure in the face or behind the eyes is a sinus problem. Because migraine and tension headache can also cause facial or eye-area pain, the rest of the symptoms matter. If you also have fever, thick nasal drainage, or ongoing sinus symptoms, that is worth discussing with a clinician.
When should I stop treating headaches at home and get checked?
Get checked if the headaches are new, becoming more frequent, interfering with daily life, waking you from sleep, or coming with nausea, light sensitivity, fever, stiff neck, eye pain, or neurologic symptoms. Sudden severe headache, headache after injury, weakness, trouble speaking, seizure, or vision loss should be treated as an emergency.
10 · References
References and supporting evidence
These sources support the points identified below. Source checking is not clinical approval.
- S1: HeadacheMedlinePlus / U.S. National Library of Medicine
Explains that tension headache is the most common type and is linked with muscle tightness in the shoulders, neck, scalp, and jaw.
- S2: MigraineMedlinePlus / U.S. National Library of Medicine
Explains the recurring, throbbing or pulsing, often one-sided pattern of migraine and supports distinguishing migraine from other headaches.
- S3: CaffeineMedlinePlus / U.S. National Library of Medicine
Explains that too much caffeine can cause headaches and related symptoms, supporting the section on caffeine as a trigger.
General information, not a diagnosis. This guide is not a substitute for care from a qualified healthcare professional. For an emergency, call 911 in the US or your local emergency number. Illustrations are conceptual and are not diagnostic images.