Tension-type headache pain is often described as a constant pressure, as if the head were being squeezed in a vise. The pain is frequently present on both sides of the head at the same time. Tension-type headache pain is typically mild to moderate, but may be severe.

According to the third edition of the International Classification of Headache Disorders, the attacks must meet the following criteria:

- A duration of between 30 minutes and 7 days.

- At least two of the following four characteristics:

- bilateral location

- pressing or tightening (non-pulsating) quality

- mild or moderate intensity

- not aggravated by routine physical activity such as walking or climbing stairs

- Both of the following:

- no nausea or vomiting

- no more than one of photophobia (sensitivity to bright light) or phonophobia (sensitivity to loud sounds)

Tension-type headaches may be accompanied by tenderness of the scalp on manual pressure during an attack.

Based on frequency, tension-type headaches can be sub-classified as

- Infrequent episodic: occurring less than once per month on average, or less than 12 episodes a year;

- Frequent episodic: occurring between 1-14 times per month on average for at least 3 months;

- Chronic: occurring 15 times a month for at least 3 months (CTTH - "chronic tension-type headache").

Chronic headache, or chronic daily headache (CDH), is classified as experiencing fifteen or more days with a headache per month. It is estimated that chronic headaches affect "4% to 5% of the general population". Chronic headaches consist of different sub-groups, primarily categorized as chronic tension-type headaches and chronic migraine headaches. The treatments for chronic headache are vast and varied. Medicinal and non-medicinal methods exist to help patients cope with chronic headache, because chronic headaches cannot be cured. Whether pharmacological or not, treatment plans are often created on an individual basis. Multiple sources recommend "multimodal treatment", which is a combination of medicinal and non-medicinal remedies. Some treatments are controversial and are still being tested for effectiveness. Suggested treatments for chronic headaches include medication, physical therapy, acupuncture, relaxation training, and biofeedback. In addition, dietary alteration and behavioral therapy or psychological therapy are other possible treatments for chronic headaches.

The pain occurs only on one side of the head (unilateral), around the eye (orbital), particularly above the eye (supraorbital), in the temple (temporal), or in any combination.

The pain of CH attack is remarkably greater than in other headache conditions, including severe migraine. The pain is typically described as burning, stabbing, boring or squeezing, and may be located near or behind the eye. As a result of the pain, those with cluster headaches may experience suicidal thoughts during an attack (giving the alternative name "suicide headache" or "suicidal headache"). It is reported as one of the most painful conditions.

Cluster headaches are recurring bouts of excruciating unilateral headache attacks of extreme intensity. The duration of a typical CH attack ranges from about 15 to 180 minutes. Most untreated attacks (about 75%) last less than 60 minutes.

The onset of an attack is rapid and most often without preliminary signs that are characteristic in migraine. Preliminary sensations of pain in the general area of attack, referred to as "shadows", may signal an imminent CH, or these symptoms may linger after an attack has passed, or even between attacks. Though CH is strictly unilateral, there are some documented cases of "side-shift" between cluster periods, or, extremely rarely, simultaneous (within the same cluster period) bilateral cluster headaches.

SUNCT often accompanies cranial autonomic symptoms, including lacrimation (tear flow), ipsilateral ptosis (drooping of the eyelid which is on the same side as the attacks), eyelid edema (swelling due to fluid accumulation), nasal blockage, and conjunctival injection (redness of eye). Attacks seldom occur without any of the cranial autonomic symptoms as in similar form of headache, short-lasting unilateral neuralgiform headache attacks with cranial autonomic features (SUNA).

The majority of SUNCT attacks occur chronically; however, some occur episodically. In chronic SUNCT, attacks can occur regularly or irregularly without a distinct refractory period, whereas in episodic SUNCT, attacks occur only for a certain period of time and then cease for another period. Episodes of attacks last from a few days to a few months, and up to 22 attack episodes in one year have been observed. SUNCT can go into remission even after a chronic period, and relapse either simultaneously or from some stimuli.

Tension headache, also known as tension-type headache, is the most common type of primary headache. The pain can radiate from the lower back of the head, the neck, eyes, or other muscle groups in the body typically affecting both sides of the head. Tension-type headaches account for nearly 90% of all headaches.

Pain medication, such as aspirin and ibuprofen, are effective for the treatment of tension headache. Tricyclic antidepressants appear to be useful for prevention. Evidence is poor for SSRIs, propranolol, and muscle relaxants.

As of 2013 tension headaches affect about 1.6 billion people (20.8% of the population) and are more common in women than men (23% to 18% respectively).

People affected by SUNCT often describe their headache attacks as excruciating pain. The attacks are severe enough to disrupt daily activities, but hospitalization is not necessary for most affected individuals.

The headaches can vary greatly in their clinical presentation and duration.

Quality of the headache has been described as dull and/or pressure-like sensation, and throbbing and/or pulsating sensation. The pain is usually on both sides of the head (in 88–93% of people with NDPH), but may be unilateral, and may be localized to any head region. The pain can fluctuate in intensity and duration, is daily, and lasts more than 3 months.

There may be accompanying photophobia, phonophobia, lightheadedness or mild nausea. Co-morbidity with mood disorders has been reported in a subset of patients.

Cranial autonomic nervous symptoms occur with painful exacerbations in 21%, and cutaneous allodynia may be present in 26%.

In 2002, Li and Rozen conducted a study of 56 patients at the Jefferson Headache Center in Philadelphia and published the following results:

- 82% of patients were able to pinpoint the exact day their headache started.

- 30% of the patients, the onset of the headache occurred in correlation with an infection or flu-like illness.

- 38% of the patients had a prior personal history of headache.

- 29% of the patients had a family history of headache.

- 68% reported nausea.

- 66% reported photophobia.

- 61% reported phonophobia.

- 55% reported lightheadedness.

Imaging and laboratory testing were unremarkable except for an unusually high number of patients who tested positive for a past Epstein-Barr virus infection.

90% of all headaches are primary headaches. Primary headaches usually first start when people are between 20 and 40 years old . The most common types of primary headaches are migraines and tension-type headaches. They have different characteristics. Migraines typically present with pulsing head pain, nausea, photophobia (sensitivity to light) and phonophobia (sensitivity to sound). Tension-type headaches usually present with non-pulsing "bandlike" pressure on both sides of the head, not accompanied by other symptoms. Other very rare types of primary headaches include:

- cluster headaches: short episodes (15–180 minutes) of severe pain, usually around one eye, with autonomic symptoms (tearing, red eye, nasal congestion) which occur at the same time every day. Cluster headaches can be treated with triptans and prevented with prednisone, ergotamine or lithium.

- trigeminal neuralgia or occipital neuralgia: shooting face pain

- hemicrania continua: continuous unilateral pain with episodes of severe pain. Hemicrania continua can be relieved by the medication indomethacin.

- primary stabbing headache: recurrent episodes of stabbing "ice pick pain" or "jabs and jolts" for 1 second to several minutes without autonomic symptoms (tearing, red eye, nasal congestion). These headaches can be treated with indomethacin.

- primary cough headache: starts suddenly and lasts for several minutes after coughing, sneezing or straining (anything that may increase pressure in the head). Serious causes (see secondary headaches red flag section) must be ruled out before a diagnosis of "benign" primary cough headache can be made.

- primary exertional headache: throbbing, pulsatile pain which starts during or after exercising, lasting for 5 minutes to 24 hours. The mechanism behind these headaches is unclear, possibly due to straining causing veins in the head to dilate, causing pain. These headaches can be prevented by not exercising too strenuously and can be treated with medications such as indomethacin.

- primary sex headache: dull, bilateral headache that starts during sexual activity and becomes much worse during orgasm. These headaches are thought to be due to lower pressure in the head during sex. It is important to realize that headaches that begin during orgasm may be due to a subarachnoid hemorrhage, so serious causes must be ruled out first. These headaches are treated by advising the person to stop sex if they develop a headache. Medications such as propranolol and diltiazem can also be helpful.

- hypnic headache: moderate-severe headache that starts a few hours after falling asleep and lasts 15–30 minutes. The headache may recur several times during night. Hypnic headaches are usually in older women. They may be treated with lithium.

Medication overuse headache is a recognized ICHD (International Classification of Headache Disorders) classification. Over the years different sets of diagnostic criteria have been proposed and revised by the major experts of headache disorders. The term MOH first appeared in the ICHD 2nd edition in 2004. It was defined as a secondary headache, with the aim of emphasising excessive drug intake as the basis of this form of headache. The two subsequent revisions of the diagnostic criteria for MOH (2005 and 2006) refined and extended the definition of the condition on the basis of both its chronicity (headache on more than 15 days/month for more than three months) and drug classes, thereby identifying the main types of MOH. In the case of ergotamine, triptans, opioids and combination medications in particular, intake on > 10 days/month for > 3 months is required, whereas simple analgesics are considered overused when they are taken on > 15 days/month for >3 months.

New daily persistent headache (NDPH) is a primary headache syndrome which can mimic chronic migraine and chronic tension-type headache. The headache is daily and unremitting from very soon after onset (within 3 days at most), usually in a person who does not have a history of a primary headache disorder. The pain can be intermittent, but lasts more than 3 months. Headache onset is abrupt and people often remember the date, circumstance and, occasionally, the time of headache onset. One retrospective study stated that over 80% of patients could state the exact date their headache began.

The cause of NDPH is unknown, and it may have more than one etiology. NDPH onset is commonly associated with an infection or flu-like illness, stressful life event, minor head trauma, and extra cranial surgery. Infection or flu-like illness and stressful life event are most often cited. The pathophysiology of NDPH is poorly understood.

The syndrome is difficult to treat and may persist for years. The age of onset ranges from 6 to greater than 70 years old, with a mean of 35 years. It is found to be more common in females in both the adult and pediatric populations. NDPH is rare. The Akershus study of chronic headache, a population based cross sectional study of 30,000 persons aged 30–44 years in Norway, found a one-year prevalence of 0.03 percent in the population.

In 1986, Vanast was the first author to describe the new daily-persistent headache (NDPH) as a benign form of chronic daily headache (CDH). The criteria for the diagnosis of NDPH were proposed in 1994 (the Silberstein–Lipton criteria) but not included in the International Classification of Headache Disorders (ICHD) until 2004.

Old headaches are usually primary headaches and are not dangerous. They are most often caused by migraines or tension headaches. Migraines are often unilateral, pulsing headaches accompanied by nausea or vomiting. There may be an aura (visual symptoms, numbness or tingling) 30–60 minutes before the headache, warning the person of a headache. Migraines may also not have auras. Tension type headaches usually have bilateral "bandlike" pressure on both sides of the head usually without nausea or vomiting. However, some symptoms from both headache groups may overlap. It is important to distinguish between the two because the treatments are different.

The mnemonic 'POUND' helps distinguish between migraines and tension type headaches. POUND stands for Pulsatile quality, 4–72 hOurs in length, Unilateral location, Nausea or vomiting, Disabling intensity. One review article found that if 4–5 of the POUND characteristics are present, migraine is 24 times as likely a diagnosis than tension type headache (likelihood ratio 24). If 3 characteristics of POUND are present, migraine is 3 times more likely a diagnosis than tension type headache (likelihood ratio 3). If only 2 POUND characteristics are present, tension type headaches are 60% more likely (likelihood ratio 0.41). Another study found the following factors independently each increase the chance of migraine over tension type headache: nausea, photophobia, phonophobia, exacerbation by physical activity, unilateral, throbbing quality, chocolate as headache trigger, cheese as headache trigger.

Cluster headaches are relatively rare (1–3 in 10,000 people) and are more common in men than women. They present with sudden onset explosive pain around one eye and are accompanied by autonomic symptoms (tearing, runny nose and red eye).

Temporomandibular jaw pain (chronic pain in the jaw joint), and cervicogenic headache (headache caused by pain in muscles of the neck) are also possible diagnoses.

For chronic, unexplained headaches, keeping a headache diary can be useful for tracking symptoms and identifying triggers, such as association with menstrual cycle, exercise and food. While mobile electronic diaries for smartphones are becoming increasingly common, a recent review found most are developed with a lack of evidence base and scientific expertise.

Medication overuse headache (MOH), also known as rebound headache usually occurs when analgesics are taken frequently to relieve headaches. Rebound headaches frequently occur daily, can be very painful and are a common cause of chronic daily headache. They typically occur in patients with an underlying headache disorder such as migraine or tension-type headache that "transforms" over time from an episodic condition to chronic daily headache due to excessive intake of acute headache relief medications.

MOH is a serious, disabling and well-characterized disorder, which represents a worldwide problem and is now considered the third-most prevalent type of headache. Population-based studies report the prevalence rate of MOH to be 1% to 2% in the general population, but its relative frequency is much higher in secondary and tertiary care.

In addition to persistent daily headache of HC, which is usually mild to moderate (and frequently severe), HC can present other symptoms. These additional symptoms of HC can be divided into three main categories:

1. Autonomic symptoms:

- conjunctival injection

- tearing

- rhinorrhea

- nasal stuffiness

- eyelid edema

- forehead sweating

2. Stabbing headaches:

- Short, "jabbing" headaches superimposed over the persistent daily headache.

- Usually lasting less than one minute.

3. Migrainous features:

- throbbing pain

- nausea and/or vomiting

- phonophobia

- photophobia

Hypnic headaches are benign primary headaches that affect the elderly, with the average age of onset being 63 ± 11 years. They are moderate, throbbing, bilateral or unilateral headaches that wake the sufferer from sleep once or multiple times a night. They typically begin a few hours after sleep begins and can last from 15–180 min. There is normally no nausea, photophobia, phonophobia or autonomic symptoms associated with the headache. They commonly occur at the same time every night possibly linking the headaches with circadian rhythm, but polysomnography has recently revealed that the onset of hypnic headaches may be associated with REM sleep.

Lithium carbonate 200–600 mg at bedtime is an effective treatment for most patients but for those that can not tolerate Lithium, Verapamil, indomethacin or methylsergilide may be tried. Two patients have also responded to flunarizine 5 mg. It has also been shown that 1–2 cups of coffee or 100–200 mg of caffeine before bed can prevent hypnic headaches.

For diagnosis of hypnic headache syndrome, headaches should occur at least 15 times per month for at least one month. Included in the differential diagnosis of a new onset nighttime headaches in the elderly is drug withdrawal, temporal arteritis, Sleep apnea, oxygen desaturated, Pheochromocytoma, intracranial causes, primary and secondary neoplasms, communicating hydrocephalus, subdural hematoma, vascular lesions, migraines, cluster headaches, chronic paroxysmal hemicrania and hypnic headache. All other causes must be ruled out before the diagnosis of hypnic headache can be made.

The following diagnostic criteria are given for hemicrania continua:

1. Headache for more than 3 months fulfilling other 3 criteria:

2. All of the following characteristics:

- Unilateral pain without side-shift

- Daily and continuous, without pain-free periods

- Moderate intensity, but with exacerbations of severe pain

3. At least one of the following autonomic features occurs during exacerbations and ipsilateral to the side of pain:

- Conjunctival injection and/or lacrimation

- Nasal congestion and/or rhinorrhea

- Ptosis and/or miosis

4. Complete response to therapeutic doses of indomethacin, although cases of hemicrania continua that do not resolve with indomethacin treatment have been documented.

A variant on hemicrania continua has also been described, in which the attacks may shift sides, although meeting the above criteria in all other respects.

Main features differentiating CPH from cluster headaches (migrainous neuralgia, above) are the higher frequency and shorter duration of attacks, higher incidence in women, and the response to treatment with indomethacin. CPH is not associated with cranial nerve palsies.

According to the third edition of the International Classification of Headache Disorders (ICHD), which terms this condition "primary headache associated with sexual activity", it normally begins as a dull headache that increases with sexual excitement, and becomes intense at orgasm. For some patients, the headache begins suddenly, often at orgasm. In two thirds of cases, it is bilateral, and unilateral in the rest. The pain lasts from one minute to 24 hours with severe intensity, or as long as 72 hours with mild intensity. Its occurrence is unpredictable, and may not follow every sexual act.

Previous editions of the ICHD divided the condition into two subforms, "preorgasmic headache" and "orgasmic headache". These subforms were merged into one entity with varying presentation because clinical studies could not distinguish them. Post-orgasmic headaches associated with posture may be better attributed to a spontaneous cerebrospinal fluid leak. Sudden, severe headaches during sexual activity may also be caused by intracerebral hemorrhage, subarachnoid hemorrhage, or cerebral infarction, which require immediate medical attention.

Psychogenic pain, also called psychalgia, is physical pain that is caused, increased, or prolonged by mental, emotional, or behavioral factors.

Headache, back pain, or stomach pain are some of the most common types of psychogenic pain. It may occur, rarely, in persons with a mental disorder, but more commonly it accompanies or is induced by social rejection, broken heart, grief, lovesickness, or other such emotional events.

Sufferers are often stigmatized, because both medical professionals and the general public tend to think that pain from psychological source is not "real". However, specialists consider that it is no less actual or hurtful than pain from other sources.

The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, "or described in terms of such damage"" (emphasis added). In the note accompanying that definition, the following can be found about pain that happens for psychological reasons:

Many people report pain in the absence of tissue damage or any likely pathophysiological cause; usually this happens for psychological reasons. There is usually no way to distinguish their experience from that due to tissue damage if we take the subjective report. If they regard their experience as pain and if they report it in the same ways as pain caused by tissue damage, it should be accepted as pain.

Medicine refers also to psychogenic pain or psychalgia as a form of chronic pain under the name of "persistent somatoform pain disorder" or "functional pain syndrome". Causes may be linked to stress, unexpressed emotional conflicts, psychosocial problems, or various mental disorders. Some specialists believe that psychogenic chronic pain exists as a protective distraction to keep dangerous repressed emotions such as anger or rage unconscious.

It remains controversial, however, that chronic pain might arise purely from emotional causes. Treatment may include psychotherapy, antidepressants, analgesics, and other remedies that are used for chronic pain in general.

The International Headache Society classifies ophthalmodynia periodica as a primary stabbing headache.

Individuals with CPH suffer multiple short, severe headaches a day, often more than five, with most lasting between 5 and 30 minutes each. When compared to cluster headaches, CPH attacks are typically shorter. Each headache is centered around the eye, temple and forehead and is localized to one side of the head. While redness and watering of the eye are associated with CPH, patients typically do not experience nausea or vomiting.

Trigeminal autonomic cephalgia (TAC) is the name for a type of primary headache that occurs with pain on one side of the head in the trigeminal nerve area and symptoms in autonomic systems on the same side, such as eye watering and redness or drooping eyelids. TACs include

- Cluster headache

- Paroxysmal hemicrania (chronic or episodic)

- Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)

- Short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA)

- Long-lasting autonomic symptoms with hemicrania (LASH)

TACs can be differentiated by the length and frequency of recurrence of the headaches.

Treatment for TACs varies depending on the exact type, but can include medication such as Indomethacin (in the case of chronic paroxysmal hemicrania) or acute and prophylactic therapy (in the case of cluster headache).

The following diagnostic criteria are given for ophthalmodynia periodica:

1. Head pain occurring as a single stab or a series of stabs

2. Solely felt in the areas surrounding the eyes and temples

3. Pain lasting only a few seconds with irregular frequency

4. No additional symptoms

5. "Not attributed to another disorder"

Migraines typically present with self-limited, recurrent severe headache associated with autonomic symptoms. About 15–30% of people with migraines experience migraines with an aura and those who have migraines with aura also frequently have migraines without aura. The severity of the pain, duration of the headache, and frequency of attacks are variable. A migraine lasting longer than 72 hours is termed status migrainosus. There are four possible phases to a migraine, although not all the phases are necessarily experienced:

- The prodrome, which occurs hours or days before the headache

- The aura, which immediately precedes the headache

- The pain phase, also known as headache phase

- The postdrome, the effects experienced following the end of a migraine attack

Vertigo is a medically recognized term for the symptom of vestibular system disturbance. It may include a feeling of rotation or illusory sensations of motion or both. The general term dizziness is used by nonmedical people for those symptoms but often refers to a feeling of light-headedness, giddiness, drowsiness, or faintness, all of which must be differentiated from true vertigo, since the latter symptoms might have other causes.

Motion sickness occurs more frequently in migraine patients (30–50% more than in controls). Benign paroxysmal vertigo of childhood is an example of migraine-associated vertigo in which headache does not often occur. Basilar artery migraine (BAM) consists of two or more symptoms (vertigo, tinnitus, decreased hearing, ataxia, dysarthria, visual symptoms in both hemifields or both eyes, diplopia, bilateral paresthesias, paresis, decreased consciousness and/or loss of consciousness) followed by throbbing headache. Auditory symptoms are rare. However, a study showed a fluctuating low-tone sensorineural hearing loss in more than 50% of patients with BAM with a noticeable change in hearing just before the onset of a migraine headache. The attacks of vertigo are usually concurrent with the headache and the family history is usually positive. The diagnostician must rule out: TIAs, and paroxysmal vestibular disorder accompanied by headache.

There is also a familial vestibulopathy, familial benign recurrent vertigo (fBRV), where episodes of vertigo occur with or without migraine headache. Testing may show profound vestibular loss. The syndrome responds to acetazolamide. Familial hemiplegic migraine (FHM) has been linked to mutations in the calcium channel gene. (Ophoff et al. 1966 cf. Lempert et al.)

Prodromal or premonitory symptoms occur in about 60% of those with migraines, with an onset that can range from two hours to two days before the start of pain or the aura. These symptoms may include a wide variety of phenomena, including altered mood, irritability, depression or euphoria, fatigue, craving for certain food(s), stiff muscles (especially in the neck), constipation or diarrhea, and sensitivity to smells or noise. This may occur in those with either migraine with aura or migraine without aura.