ANORGASMIA
ANTHRACOSIS
A
The causes of anorexia are unclear, but
the condition may be linked to a lack of
self-worth that leads to excessive con-
cern over physical appearance. Normal
dieting may develop into starvation.
In the early stages, sufferers may be
overactive
and
exercise
excessively.
They are obsessed with food, and often
make complicated meals for their fami-
lies, but are reluctant to eat socially and
manage to avoid eating the meals
themselves. As weight loss continues,
they become tired and weak, the skin
becomes dry, lanugo hair (fine, downy
hair) grows on the body, and normal
hair becomes thinner. Starvation leads
to
am enorrhoea
in many women. Some
anorexics sometimes make themselves
vomit or take
laxative drugs
or
diuretic
drugs
to promote weight loss (see
bulimia).
Chemical imbalances as a
result of starvation with or without
vomiting can cause potentially fatal car-
diac
arrhythmias.
Hospital treatment is often necessary
and is usually based on a closely con-
trolled feeding programme, combined
with
psychotherapy
or
family therapy.
For some people,
antidepressant drugs
may be helpful. Many sufferers relapse
after treatment, and long-term psycho-
therapy is required.
anorgasmia
Inability to achieve orgasm
(see
orgasm, lack
of).
anosmia
Loss of the sense of
smell.
anoxia
A complete absence of oxygen
in a body tissue. Anoxia causes disrup-
tion of cell
metabolism
and cell death
unless corrected within a few minutes.
Anoxia occurs during cardiopulmonary
arrest or asphyxiation and will cause
permanent organ damage or even death
if not corrected. (See also
hypoxia.)
antacid drugs
Drugs taken to relieve
the symptoms of
indigestion
,
heartburn
,
oesophagitis
,
acid reflux
, and
peptic ulcer
.
Antacids usually contain compounds of
magnesium
or
aluminium
, which neutra-
lize stomach acid. Some also contain
alginates, which protect the lining of
the oesophagus from stomach acid, or
dimeticone, an antifoaming agent, which
helps to relieve flatulence.
Aluminium may cause constipation
and magnesium may cause diarrhoea;
but these effects may be avoided if a
preparation contains both ingredients.
Antacids interfere with the absorption
of many drugs and should not be taken
at the same time as other drugs.
antagonist
Having an opposing effect.
For example, antagonist drugs counter-
act the effects of naturally occurring
chemicals in the body. (see also
agonist
.)
antenatal care
The care of a pregnant
woman and her unborn baby through-
out a pregnancy. Such care involves
regular visits to a doctor or midwife,
who performs abdominal examinations,
blood and urine tests, and monitoring
of blood pressure and fetal growth to
detect disease or potential problems.
U.trasound scanning
is carried out to
identify abnormalities in the fetus.
Chori-
onic villus sampling
or
amniocentesis
may be performed if the baby is thought
to be at increased risk of a
chromosomal
abnormality
or a
genetic disorder
. The
woman is also advised on general asp-
ects of pregnancy, such as diet, exercise,
techniques to help her with childbirth.
(See also
childbirth
,
natural
.)
antepartum haemorrhage
Bleeding
from the vagina after the 28th week of
pregnancy. Antepartum haemorrhage is
most commonly due to a problem with
the placenta, such as
placenta praevia
or
placental abruption
. Bleeding can
also be caused by
cervical erosion
or
other disorders of the cervix or vagina.
Admission to hospital is necessary for
investigation and treatment.
Ultrasound
scanning
is used to diagnose problems
with the placenta. If the bleeding is
severe, the woman is given a
blood
transfusion
, and the baby is delivered
immediately by
caesarean section
.
anterior
Relating to the front of the
body. In human
anatomy
, the term is
synonymous with
ventral.
anthelmintic drugs
A group of drugs
that are used to eradicate
worm infes-
tations.
Possible side effects include
nausea, abdominal pain, rash, head-
ache, and dizziness.
anthracosis
An outdated term for coal
worker's
pneumoconiosis.
Anthracosis is
a lung disease caused by the inhalation
of large amounts of coal dust over a
period of many years.
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