becomes totally incapacitated because
the disease usually progresses very
slowly. Life expectancy is normal.
perphenazineA phenothiazine-type anti-
psychotic drugused to relieve symptoms
in psychiatric disorders, such as schizo-
phrenia; to sedate agitated or anxious
patients; and sometimes to relieve sev-
ere nausea and vomiting.
Possible adverse effects include abnor-
mal movements of the face and limbs,
drowsiness, blurred vision, stuffy nose,
and headache. Long-term use of the drug
may causeparkinsonism.
persistent vegetative stateLong-term
unconsciousnesscaused by damage to
areas of the brain that control higher
mental functions. The eyes may open
and close, and there may be random
movements of the limbs, but there is
no response to stimuli such as pain.
Basic functions such as breathing and
heartbeat are not affected. There is no
treatment to reverse the situation, but,
with good nursing care, survival for
months or years is possible.
personalityThe sum of a person’s traits,
habits, and experiences. Temperament,
intelligence, emotion, and motivation are
important aspects. The development of
personality seems to depend on the
interaction of heredity and environment.
personality disordersA group of con-
ditions characterized by a failure to
learn from experience or to adapt appro-
priately to changes, resulting in distress
and impairment of social functioning.
Personality disorders are ways of behav-
ing that may become especially obvious
during periods of stress. They are usual-
ly first recognizable in adolescence and
continue throughout life, often leading
to depressionor anxiety.
Specific types of personality disorders
are divided into 3 groups but there is
often overlap. The 1st group is charac-
terized by eccentric behaviour. Paranoid
people show suspiciousness and mis-
trust of others, schizoid people are cold
emotionally, and schizotypal persona-
lities have behaviour oddities similar to
those of schizophrenia, but less severe.
In the 2nd group, behaviour tends to be
dramatic. Histrionic people are excit-
able and constantly crave stimulation,
narcissists have an exaggerated sense
of their own importance (see narcissism),
and people with antisocial personality
disorder fail to conform to accepted
social standards of behaviour.
People in the 3rd group show anxiety
and fear. Dependent personalities lack
the self-confidence to function inde-
pendently(see dependence). Those with
compulsive personalities are rigid in
their habits (see obsessive–compulsive
disorder), and passive-aggressive peo-
ple resist demands from others.
Treatment is usually counselling, psy-
chotherapy, and behaviour therapy.
personality testsQuestionnaires de-
signed to define various personality
traits or types. Tests may be designed to
detect psychiatric symptoms, underly-
ing personality traits, how outgoing or
reserved a person is, and predisposition
to developing neurotic illness.
perspirationThe production and ex-
cretion of sweat from the sweat glands.
Perspiration is another name for sweat.
Perthes’ diseaseInflammation of an
epiphysisof the head of the femur.
The disease is a type ofosteochondritis
juvenilis, thought to be due to disrupted
blood supply to the bone. The condition
is most common in boys aged 5–10, and
usually affects 1 hip. Symptoms include
pain in the thigh and groin, and a limp
on the affected side. Diagnosis is made
with X-rays. Treatment may be rest for a
few weeks, followed by splinting of the
hip, or surgery. The disease usually clears
up by itself within 3 years, but the hip
may be permanently deformed.
pertussisA highly contagious infectious
disease, also called whooping cough,
which mainly affects infants and young
children. The main features of the ill-
ness are bouts of coughing, often ending
in a characteristic “whoop”. The main
cause is infection with BORDETELLA PER-
TUSSISbacteria, which are spread in
airborne droplets.
After an incubation periodof 7–10 days,
the illness starts with a mild cough,
sneezing, nasal discharge, fever, and
sore eyes. After a few days, the cough
becomes more persistent and severe,
especially at night. Whooping occurs in
most cases. Sometimes the cough canPERPHENAZINE PERTUSSIS
P