I
ANTIDIABETIC DRUGS
stroke
and
transient ischaemic attack
(symptoms of stroke lasting less than
24 hours). Anticoagulant drugs are also
given long-term to prevent abnormal
blood clotting after major surgery (esp-
ecially
heart-valve
replacement)
or
during haemodialysis (see
dialysis).
The most common anticoagulants are
heparin
and the newer heparin-derived
drugs, such as tinzaparin, all of which
have to be given by injection, and
warf-
arin,
which is taken orally. Heparin is
usually given initially and is then with-
drawn
when
warfarin
therapy
has
become effective.
HOW THEY WORK
Anticoagulant drugs reduce the activity
of certain enzymes, known as blood
clotting factors, that are needed for the
blood to clot. Anticoagulants do not dis-
solve clots that have already formed,
which can be treated with
thrombolytic
drugs,
however they may help to stabi-
lize an existing clot so that it does not
brake away causing an
embolism
(block-
age of an artery by a blood clot).
SIDE EFFECTS
Excessive doses of warfarin or its use
with other drugs, such as aspirin and
alcohol,
may
increase
the
risk
of
unwanted bleeding. Regular monitoring
with
blood-clotting tests
is required.
WARNING
A doctor should always be consulted
before any other drug is taken during
anticoagulant treatment.
anticonvulsant drugs
COMMON DRUGS
• Carbamazepine •Clobazam •Clomethiazole
• Clonazepam •Diazepam •Ethosuximide
• Gabapentin •Lamotrigine •Lorazepam
• Phenobarbital •Phenytoin •Piracetam
• Primidone •Sodium valproate •Tiagabine
• Topiramate •Vigabatrin
A group of drugs used to treat or pre-
vent seizures. Anticonvulsant drugs are
used mainly in the treatment of
epilepsy
,
but they are also prescribed to prevent
seizures following serious
head injury
or
some types of brain surgery. They may
be needed to control seizures in children
with a high fever (see
convulsions, febrile).
Different drugs are effective at treating
different types of seizure.
HOW THEY WORK
Seizures are caused by an abnormally
high level of electrical activity in the
brain. Anticonvulsant drugs have an
inhibitory effect that suppresses this
excessive electrical activity, thereby pre-
venting its spread throughout areas of
the brain. If seizures continue following
treatment with an anticonvulsant, two
drugs may be used in combination.
SIDE EFFECTS
Anticonvulsants may produce various
side effects, including impaired mem-
ory,
reduced
concentration,
poor
coordination, and fatigue. If the side
effects are troublesome, an alternative
anticonvulsant can be tried. The dose of
an anticonvulsant drug may need to be
monitored using
blood tests
.
WARNING
The dosage of anticonvulsants should
not
be
reduced
or
the
treatment
stopped without a doctor being con-
sulted first. the doctor will supervise a
gradual reduction in dosage. Stopping
the drugs abruptly could cause with-
drawal symptoms and a recurrence of
the original problem.
antidepressant drugs
COMMON DRUGS
SELECTIVE SEROTONIN REUPTAKE INHIBITORS
(SSRIS
) •Citalopram •Fluoxetine
• Fluvoxamine •Paroxetine •Sertraline
t r icy clics (TCAS)
•Amitriptyline •Amoxapine
• Clomipramine •Dosulepin •Doxepin
• Imipramine •Lofepramine •Nortriptyline
• Trimipramine
MONOAMINE OXIDASE INHIBITORS (MAOIS)
• Isocarboxazid •Moclobemide •Phenelzine
others
•Flupentixol •Maprotiline •Mianserin
• Mirtazapine •Reboxetine •Trazodone
• Venlafaxine
Drugs used in the treatment of
depres-
sion.
Most
of the
commonly
used
antidepressant drugs belong to one of
the following groups:
tricyclic antidepres-
sants
(TCAs),
selective serotonin reuptake
inhibitors
(SSRIs), and
monoamine oxi-
dase inhibitors
(MAOIs).
HOW THEY WORK
Normally, brain cells release enough
neurotransmitters
(chemical messengers)
in the brain to stimulate nearby brain
cells. Neurotransmitters are constantly
being reabsorbed into the brain cells by
another chemical, monoamine oxidase.
Depression is thought to be due to a
reduction in the release of neurotrans-
mitters. TCAs increase the level of the
neurotransmitters noradrenaline (norep-
inephrine) and serotonin by preventing
their
reabsorption.
MAOIs work
by
blocking the action of monoamine oxi-
dase, which increases neurotransmitter
levels. SSRIs only prevent the reabsorp-
tion of serotonin.
Antidepressants
usually
relieve
the
symptoms of depression, but it often
takes two to three weeks for any benefi-
cial effects to be felt. Treatment usually
lasts for at least six months; and the
dosage
is
reduced
gradually
before
being stopped altogether.
SIDE EFFECTS
TCAs may cause constipation, a dry
mouth, drowsiness, blurred vision, uri-
nary difficulty, and irregular heartbeat.
SSRIs may cause nausea, indigestion,
loss of appetite, or sexual difficulties but
are less dangerous in overdose than
other antidepressants. MAOIs may inter-
act
with
foods
and
other
drugs,
although
moclobemide
is less likely to
cause problems.
Antidepressants are not addictive, but
abrupt withdrawal of some types can
result in physical symptoms and should
therefore be avoided.
WARNING
Food and drink containing tyramine
(for example, cheese and red wine) and
other drugs may cause a dangerous rise
in blood pressure when taken during
treatment with an MAOI. Always tell your
doctor if you are taking an MAOI.
antidiabetic drugs
COMMON DRUGS
Sulphonylurea drugs
•Chlorpropamide
• Glibenclamide •Gliclazide •Glimepiride
• Glipizide •Gliquidone •Tolbutamide
others
•Acarbose •Glucagon^Guar gum
•Insulin •Insulin lispro •Metformin
•Repaglinide •Rosiglitazone
A group of drugs that are used to treat
diabetes mellitus,
in which a lack of
insulin,
or
resistance
to
its
actions,
results in
hyperglycaemia
(high levels of
glucose in the blood). A wide range
of antidiabetics are used to keep the
blood glucose level as close to normal
as possible, thereby reducing the risk
of
complications
such
as
vascular
(blood
vessel)
disease.
Antidiabetic
drugs include insulin, which must be
administered
by
injection,
and
oral
hypoglycaemics (see
hypoglycaemics, oral)
such as
glibenclamide
and
metformin.
HOW THEY WORK
Most antidiabetic drugs promote the
uptake of glucose into the body tissues,
helping to prevent an excessive rise in
blood glucose levels. However, different
antidiabetics work in different ways.
Acarbose
and
guar gum
reduce or slow
the absorption of carbohydrate from
the intestines after meals.
Repaglinide
A
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