To date, thirteen forms of headache have been identified, which in turn are divided into more than ninety different ‘subcategories’.
Let us therefore see what the main forms of headache are.
The first distinction is between primary and secondary headaches.
The former are themselves real diseases and are not always triggered by specific, immediately identifiable causes.
Secondary headaches, also called symptomatic headaches, on the other hand, result from other diseases, such as sinusitis and neuralgia.
The most common headaches are primary headaches. Of these, the three main ones are migraine, tension-type headache and cluster headache.
According to estimates by the World Health Organisation, half of the world’s population has suffered at least one episode of tension-type headache in their lifetime and at least 10 per cent have migraine.
These headaches are episodic if the pain attacks are sporadic in frequency, occurring for less than fifteen days per month.
They become chronic, on the other hand, when the pain appears with a high frequency, for at least fifteen days a month, for more than six months, without responding to treatment and often associated with depression and disability.
The form that chronicises most easily is migraine.
Headaches can manifest themselves differently in each case: each form is characterised by certain symptoms and each attack takes on different connotations.
As the name implies, the main manifestation is pain in the head.
In some cases, it is modest and compatible with daily life or at least easily resolved with the adoption of small measures.
Sometimes, on the other hand, the crises are particularly strong and disabling: they do not allow one to devote oneself to work or study, they prevent one from having a normal social life and force one to take to bed or at least isolate oneself (in this case we speak of severe headaches).
The headache may then be associated with other symptoms depending on the case, such as discomfort towards lights and noises, nausea, vomiting, muscular pains.
Causes of headache
Primary headaches, of whatever type, usually result from the interaction of genetic predisposition, organic causes and triggering factors.
Organic causes are represented by alterations in the body’s internal physiological mechanisms and processes.
Triggering factors, on the other hand, are the ‘triggers’ that trigger the organic alterations.
It must be known that not all people react in the same way to the same triggers.
The main organic triggers of headaches are:
• changes in the blood vessels that supply the brain. In particular, distention, dilation, restriction or
• compression of intra- and/or extra-cranial arteries and veins can cause headaches;
compression, stretching or
• inflammation of cranial nerves;
inflammation, contraction or compression of extra-cranial and cervical muscles;
• inflammation of the meninges, the connective membranes that surround the brain and spinal cord.
Among the triggers of headaches are:
• emotional stress and physical exhaustion;
• an unhealthy diet (there are certain foods that promote pain attacks in some people);
• a low sugar intake;
• incorrect posture;
• jaw problems;
• atmospheric variations;
• exposure to certain smells and noises;
• alterations in the sleep-wake rhythm;
• alcohol consumption;
• the use of certain drugs;
• the use of electronic devices.
Headache is considered a female disease. In fact, it affects women more frequently.
Especially during the fertile period, a clear prevalence of the disorder is observed in the female sex compared to the male.
One of the reasons for this greater susceptibility of women may lie in the hormonal changes they are subjected to during their lives.
The most common and widespread headache is tension headache.
According to the most accepted theory, it is almost always caused by an involuntary and continuous contraction of the muscles in the neck, forehead, temples, neck and shoulders.
One should know, in fact, that when muscles are tense and fatigued, they produce an increased amount of lactic acid, a substance that causes a sort of intoxicated state of the cells.
At the level of the skull, this situation can favour the development and continuation of headaches.
This form of headache, however, may depend on more strictly neurological causes, such as alterations in the brain centres that control pain perception and stress tolerance.
The main factors that trigger this headache are:
stress, anxiety, nervous upset;
incorrect postures that put tension on the neck muscles;
drug abuse, which causes addiction;
problems with the jaw joint;
alterations in the sleep-wake rhythm.
How tension headache manifests itself
In most cases, tension headache manifests itself as a headlock tightening the head, giving rise to the famous ‘circle’.
The pain tends to be localised in the occipital region, i.e. the back of the skull, above the nape of the neck.
In some people, however, it is concentrated at eye level or is spread over the entire head.
Frequently, the headache is bilateral, i.e. it affects both the right and the left side of the body, and is described as a heavy, constricting feeling.
Sometimes, the pain is accompanied by stiffness in the back of the neck and anxious manifestations.
Attacks last between half an hour and a week.
After tension headaches, this is the most common headache.
It usually causes an intense pain of a pulsating nature, which starts slowly and appears on one side of the head, almost always involving the frontal region above the eye.
Later, the throbbing intensifies and eventually involves the forehead and temple as well.
The pain is typically associated with nausea, vomiting, discomfort to light and noise and intolerance to physical exertion.
Attacks vary in duration and may last for several consecutive days.
Cluster headache is less common than tension-type headache and migraine, but it is still the third most common type of primary headache.
Incidentally, it is the most disabling headache of this group, to the extent that it was once also called suicide headache because of the intense and violent pain that characterises it.
It is so called because the crises are close together (occurring at fairly short intervals) and cluster at certain times of the day and year.
During the cluster, i.e. the period during which the crises appear, one can have from one crisis every two days to several crises in 24 hours.
According to recent theories, the pain stimulus originates in the grey matter of the hypothalamus (part of the brain) and then involves the pain pathways up to the face.
According to other widely accepted theories, however, headache is linked to hormonal and nervous alterations, such as the abnormal production of melatonin, a hormone normally secreted by the pineal gland (an endocrine gland located inside the skull) during the night, which has an effect on sleep regulation.
The main factors that can trigger cluster headaches are:
use of alcohol, which has a powerful vasodilating action;
altered sleeping and waking rhythms;
consumption of vasodilating substances contained in food (such as nitrates added to cold cuts);
certain drugs (trinitrin and other vasodilators used by people with heart disease).
What it causes
The pain triggered by cluster headache is very intense, piercing and stabbing.
It is localised to one side of the head, around the eye and cheekbone, but may radiate to the temple, jaw, nose, dental arch or chin.
In some cases the whole side of the skull is affected by the pain, even the hair follicles.
The crisis starts quickly and reaches maximum intensity within 2-15 minutes.
It may last from 15 minutes to three hours. Then it quickly diminishes until it disappears completely.
The person cannot sit still, as holding a position can increase the pain.
To seek relief, he/she tends to walk back and forth, hit himself/herself and/or press down on the painful side with hands or objects.
Lying down worsens the pain and sometimes prolongs the attack.
The headache is associated with other signs and symptoms such as eyelid drooping, redness of the face, tearing, nasal congestion, reddening and irritation of the conjunctiva, redness and swelling of the painful eye, pupil constriction.