Headache
This condition affects 80 – 90% of
people per year
Most
headaches are not a serious risk to health
A
benign headache can be easily treated by taking an aspirin or other simple
painkiller.
Many
types of headaches are the result of a stressful lifestyle
However,
headaches may be a warning sign of more serious disorders
In
diagnosing headaches, the patient’s history is all important
Description
Almost everyone suffers from a headache from time to time. Most
headaches are transient annoyances that disappear with the help of an analgesic.
But for one person in ten, a headache is an excruciating experience, and might
herald some serious disorder.
About
15% of the population have headaches severe or frequent enough to consult a
doctor. In fact, headache is the most common cause of pain which prompts
patients to consult their GP.
Even
children get headaches, some well before the age of ten. Before puberty,
headaches are more common in boys.
In
adults, headaches are four times more prevalent in women and often linked to
menstrual fluctuations. In both sexes the frequency and severity of headaches
decline with advancing years.
What are
the causes?
The most common cause of
headache is scalp and neck "muscle contraction" or tension headache. This
affects 20% of the population. Tension headaches are usually in relation to
stress or anxiety.
Vascular headaches, namely
migraine and cluster headaches, make up the other large group of headaches –
affecting 5 – 10% of the population.
Both tension and vascular headaches can occur in an individual at the
same time. In practice, the distinction between these two entities is often less
clear-cut, and there may be an element of both muscle tension and a vascular
component at the same time.
Headaches
due to infection of surrounding structures: sinus infection, tonsillitis,
toothache, meningitis.
Headache due to inflammation
of surrounding tissues: cervical spine arthritis, constant coughing, straining
of the eyes, acute glaucoma, trigeminal neuralgia and temporal arteritis
Certain conditions will cause
a stretching or pulling of pain-sensitive parts and inner structures of the
head. These include concussion and other head trauma, strokes, brain tumours and
spinal taps (lumbar puncture).
A number of metabolic, toxic or environmental causes are:
The use of certain medications
(side-effects)
Eating
or drinking iced foods and fluids
The
use or withdrawal of alcohol ("hangover"), caffeine, or other analgesic drugs
(analgesic headaches)
Breathing
in smoke or fumes from chemicals
Repeated exposure to nitrate compounds
(found in heart medicine and dynamite; also used in a meat preservative, sodium
nitrate – such as in hot-dogs and bacon)
Exposure
to materials containing chemical solvents (for example benzene, turpentine,
spray adhesives, rubber cement and certain inks)
Eating foods (such as Chinese food)
prepared with monosodium glutamate, a flavour enhancer
Exposure
to poisons such as insecticides, lead and carbon tetrachloride
Use of drugs such as amphetamines
High
altitudes (above 4 500m)
High
blood sugar (hyperglycemia)
Low
blood sugar (hypoglycemia)
Low
calcium levels in the blood (hypocalcaemia)
Kidney
failure (uraemia)
If a headache is caused by a serious illness, other symptoms are
often present, such as vomiting, dizziness or changes in vision.
How is
it diagnosed?
The headache history is, by far, the most important tool a doctor has
to evaluate headache. Keep a headache diary.
In
diagnosing headaches, the patient’s history is all important. A careful physical
examination will be done to check for clues to possible headache causes and also
to check the nervous system. The exam can help determine whether further testing
is needed.
People
with tension-type, migraine or cluster headaches usually will have a normal
physical exam.
Any abnormal results in the physical exam may suggest a possible
underlying cause of headache. Abnormal results may include:
Fever,
which may indicate an infection such as sinusitis. Headache with fever, stiff
neck, nausea and vomiting may indicate meningitis
Headache
that began suddenly in a person who has not had headaches before, or a dramatic
change in an established headache pattern
Headache that follows any form of
physical exertion, such as exercise, sexual activity, coughing or bending (these
types of headaches are usually not caused by a serious problem, but occasionally
they can be related to an aneurysm)
Abnormal
speech, eye movements, walking, co-ordination or reflexes
Abnormal eye exam, which indicates
there may be increased pressure inside the skull
High
blood pressure
Other
findings, such as arthritis, which may suggest autoimmune disease
The history and physical exam are all that is needed to diagnose
benign headaches, including tension-type and migraine headaches. Additional
tests are only needed to help diagnose other conditions which may cause symptoms
like those of tension-type and migraine headaches.
Imaging
tests, such as MRI or CT scan, may be needed if your doctor suspects there is an
underlying organic cause such as an aneurysm or brain tumour (although these are
quite rare). Your doctor may order an imaging test if:
Your headaches continue to
get worse despite conventional treatment.
The
part of the physical exam that checks your nervous system is not normal. Most
people with tension-type and migraine headaches have normal results in their
nervous system exam.
Imaging tests that may be used in these cases include:
Computed tomography (CT)
Magnetic
resonance imaging (MRI)
Magnetic resonance
angiography (MRA)
Any person over the age of 55 with a recent onset headaches should be
tested for temporal arteritis by means of a blood test (ESR).
How is
it treated?
An initial and fundamentally important step in the management of
headache is to differentiate those headaches that are the result of other, often
serious, conditions ('secondary' headaches) from headaches that are not caused
by an underlying disease process ('primary' headaches).
Although
symptomatic treatment of pain is also necessary in secondary headaches, it is
crucial to treat the underlying cause. In the case of a brain tumor, this may
mean surgical excision or a shunt to reduce raised intracranial pressure;
antibiotics for bacterial meningitis; and surgical drainage of an intracranial
hemorrhage.
Primary
headaches are the far larger group, and include tension headaches and migraine.
These headaches are managed symptomatically - there is no underlying disease to
also take care of.
Lifestyle
There are several common-sense courses of action that may well
prevent headaches in the first place: A change in lifestyle that reduces stress
may be enough.
Some
patients notice that certain situations or habitual patterns of behaviour are
likely to cause headache. Avoiding certain trigger foods and chemical compounds
(perfumes, smoke) may be central to the management of migraine. In most people,
getting regular exercise, avoiding excessive caffeine and alcohol, stopping
smoking and ensuring adequate hydration are cornerstones of treatment, and are
just as important as drug management. They also have all sorts of other
benefits.
Medication
Drugs for headache are either prophylactic or symptomatic.
Prophylactic medications are taken daily and are directed towards preventing the
headache from developing in the first place. They are not pain medications.
Symptomatic or “abortive” medications are pain medications - analgesics - and
are designed to stop the headache once it has started. Often a trial-and-error
approach is necessary to match an individual patient with the most suitable
medication.
There
are a wide variety of prophylactic medications. Tricyclic antidepressants, like
amitryptyline, are frequently used, and can ease headache even in those patients
not clinically depressed. Other medications include several of the
anti-epileptic drugs and the calcium channel blockers. Beta-blockers, used to
lower blood pressure in other patients, are effective in migraine.
Once a
headache has taken hold, abortive medications are used. These include simple
analgesics like paracetamol and aspirin, anti-inflammatories and muscle
relaxants. Narcotic analgesics may be necessary for the most severe headaches,
but they are best limited to one-off usage, and should not be prescribed
longer-term, as they are habit-forming.
Migraine
is often associated with intense nausea, and an anti-emetic may be enough to
halt a migraine. Medications that act on the caliber of blood vessels have an
important place in migraine therapy - the ergot drugs of old have largely been
replaced by the newer “triptan” medications like sumatriptan (Imitrex), which
has oral, subcutaneous and intranasal forms. Unusual primary headaches like
cluster may respond to breathing Oxygen.
It
should be mentioned that although there are many efficacious medications for
headache, all have side-effects, and so should be used judiciously. In fact,
so-called “rebound headache” is a well-recognised result of medication overuse,
and if severe, may necessitate hospitalisation for medication withdrawal.
