the liver. Medical attention is required
if the intoxication has resulted in
coma. For the chronic mental, physical,
and social effects of long-term heavy
drinking, see alcohol dependenceand
alcohol-related disorders.
alcoholismSee alcohol dependence.
alcohol-related disordersA wide var-
iety of physical and mental disorders
associated with heavy, prolonged con-
sumption of alcohol.
High alcohol consumption increases
the risk of cancers of the mouth, tongue,
pharynx (throat), larynx (voice box), and
oesophagus, especially if combined with
smoking. Incidence of liver cancer, as
well as the liver diseases alcoholic hep-
atitis and cirrhosis, is higher among
alcoholics. High alcohol consumption
increases the risk of cardiomyopathy,
hypertension, and stroke. Alcohol irri-
tates the digestive tract and may cause
gastritis. Heavy drinking in pregnancy
increases the risk of miscarriage and
fetal alcohol syndrome. Alcoholics are
more likely to suffer from anxietyand
depressionand to develop dementia.
Many alcoholics have a poor diet and
are prone to diseases caused by nutri-
tional deficiency, particularly of thiamine
(see vitamin B complex). Severe thia-
mine deficiency, called beriberi,disturbs
nerve function, causing cramps, numb-
ness, and weakness in the legs and
hands. Its effects on the brain can cause
confusion, disturbances of speech and
gait, and eventual coma (see Wernicke–
Korsakoff syndrome). Severe thiamine
deficiency can also cause heart failure.
A prolonged high level of alcohol in
the blood and tissues can disturb body
chemistry, resulting in hypoglycaemia
(reduced glucose in the blood) and
hyperlipidaemia (increased fat in the
blood). These may damage the heart,
liver, blood vessels, and brain; irrevers-
ible damage may cause premature death.
aldosteroneA hormone secreted by
the adrenal cortex (the outer part of the
adrenal glands). Aldosterone acts on the
kidneys to regulate the concentrations
of sodium and potassium in the blood
and tissues and control blood pressure.
Production of aldosterone is stimulated
mainly by the action of angiotensinII, achemical produced by a series of reac-
tions involving the enzymes reninand
angiotensin-converting enzyme. Aldos-
terone productionis also stimulated by
the action of ACTH, which is produced
by the pituitary gland.
aldosteronismA disorder that results
from the excessive production of the
hormone aldosteronefrom one or both
adrenal glands. Aldosteronism caused
by an adrenal tumour is known as
Conn’s syndrome. Aldosteronism may
also be caused by disorders, such as
heart failureor liver damage, that reduce
the flow of blood through the kidneys.
Reduced blood flow through the kid-
neys leads to overproduction of renin
and angiotensin, which, in turn, leads to
excessive aldosterone production.
Symptoms are directly related to the
actions of aldosterone. Too much sodium
is retained in the body, leading to a rise
in blood pressure, and excess potassium
is lost in the urine. Low potassium cau-
ses tiredness and muscle weakness and
impairs kidney function, leading to thirst
and overproduction of urine.
Treatment in all cases includes res-
triction of dietary salt and use of the
diuretic drug spironolactone. If the cause
of aldosteronism is an adrenal tumour,
this may be surgically removed.
alendronate sodium See alendronic
acid.
alendronic acid A bisphosphonate drug
used in the treatment of osteoporosis
and Paget’s diseaseof bone. The most
common side effect is inflammation of
the oesophagus, which causes heart-
burn or difficulty in swallowing. Other
side effects can include headache and
abdominal pain.
Alexander techniqueA therapy that
aims to improve health by teaching peo-
ple to stand and move more efficiently.
The technique is based on the belief
that bad patterns of body movement
interfere with the proper functioning of
the body and contribute to the develop-
ment of disease.
alexiaWord blindness; inability to rec-
ognize and name written words. Alexia
is caused by damage to part of the cere-
brum (the main mass of the brain) by a
stroke, for example. It severely disruptsALCOHOLISM ALEXIAA