I
ANTIBODY
Pulmonary
anthrax
causes
severe
breathing difficulty and may be fatal
despite intensive treatment.
antiallergy drugs
Drugs used to treat or prevent allergic
reactions (see
allergy).
There are several
types
of antiallergy
drug,
including
antihistamine drugs,
leukotriene receptor
antagonists,
sodium cromoglicate,
and
corticosteroid drugs.
antianxiety drugs
A group of drugs that are used to relieve
the symptoms of
anxiety
.
Benzodiazepine
drugs,
buspirone, and
beta-blocker drugs
are the three main types of antianxiety
drug, although
antidepressant drugs
are
often used. In most cases, the under-
lying
disorder
is
best
treated
by
counselling,
psychotherapy,
or
other
forms of therapy.
Benzodiazepine drugs promote men-
tal and physical relaxation by reducing
nerve activity in the brain; they can also
be used to treat insomnia but their use
for this purpose is avoided because they
are addictive; buspirone is less addictive.
Beta-blockers reduce only the physical
symptoms of anxiety, such as shaking
and palpitations, and are not addictive.
antiarrhythmic drugs
A group of drugs used to prevent or
treat different types of
arrhythmia
(irreg-
ular heartbeat).
A number of drugs are used to pre-
vent intermittent arrhythmias or slow
the rate if an arrhythmia is persistent.
These include
beta-blocker drugs
,
calcium
channel blockers, digitalis drugs, amioda-
rone, disopyramide,
flecainide,
lidocaine
(lignocaine), mexiletine, and
procaina-
mide.
Some antiarrhythmic drugs, such
as adenosine and bretyllium, may only
be used in hospital. They may be given
intravenously to treat arrhythmias that
are causing symptoms such as breath-
lessness or chest pain.
HOW THEY WORK
The heart’s pumping action is governed
by
electrical impulses.
Some
antiar-
rhythmics alter these impulses within,
or on their way to, the heart; others
affect the heart muscle’s response to the
impulses received.
SIDE EFFECTS
Side effects of antiarrhythmic drugs are
common, and they often include nausea
and a rash. Some can result in tiredness
or breathlessness because they reduce
the pumping ability of the heart.
antibacterial drugs
A group of drugs that are used to treat
infection
due to
bacteria.
The
term
antibacterial was once used to describe
only those
antibiotic drugs
that had been
produced synthetically rather than natu-
rally. The two terms are now used
interchangeably.
antibiotic drugs
COMMON DRUGS
am inoglycosides
•Amikacin •Gentamicin
• Neomycin •Netilmicin •Streptomycin
• Tobramycin
cephalosporins
•Cefaclor •Cefadroxil
• Cefalexin •Cefamandole •Cefazolin
• Cefixime •Cefotaxime •Cefoxitin
• Cefpodoxime •Cefradine •Ceftazidime
m acrolid es
•Azithromycin •Clarithromycin
• Erythromycin
pen icillin s
•Amoxicillin •Ampicillin
• Azlocillin •Aztreonam •Benzylpenicillin
• Co-amoxiclav •Co-fluampicil •Flucloxacillin
• Imipenem • Phenoxymethylpenicillin
tetracyclines
•Doxycycline •Oxytetracycline
• Tetracycline
others
•Chloramphenicol •Ciprofloxacin
• Colistin • Fusidic acid •Metronidazole
• Rifampicin •Spectinomycin •Teicoplanin
• Trimethoprim •Vancomycin
A group of drugs used to treat infec-
tions caused by
bacteria
and to prevent
bacterial infection in individuals who
are
immunocompromized.
Most of the
commonly used antibiotic drugs belong
to one of the following classes:
amino-
glycosides
,
cephalosporins
,
macrolides
,
penicillins,
and
tetracyclines.
Some antibi-
otics are effective against only certain
types of bacteria; others, which are
known as broad-spectrum antibiotics,
are effective against a wide range.
ANTIBIOTIC RESISTANCE
Some bacteria develop resistance to a
previously effective antibiotic drug. This
resistance is most likely to occur during
long-term treatment. Some alternative
antibiotics are available to treat bacteria
that have become resistant to the more
commonly prescribed drugs.
SIDE EFFECTS
Most antibiotic drugs can cause nausea,
diarrhoea, or a rash. Antibiotics may
disturb the normal balance of “good”
bacteria in the body This can cause
problems such as
candidiasis
(thrush),
in which there is excess growth of fun-
gus.
Some
individuals
experience
a
severe allergic reaction to the drugs,
resulting in facial swelling, itching, or
breathing difficulty.
WARNING
Patients should inform their doctor of
any previous allergic reaction that they
have had to an antibiotic drug.
antibody
A protein
that is
made
by
certain
lymphocytes
(white
blood
cells)
to
neutralize an
antigen
(foreign protein)
in the body Bacteria, viruses, and other
microorganisms contain a number of
antigens; antibodies that are formed
HOW ANTIBIOTICS WORK
Antibiotic drugs are either bactericidal or bacteriostatic. Bactericidal antibiotics,
such as penicillins and cephalosporins, kill bacteria directly. Bacteriostatic
antibiotics, such as erythromycin, halt growth and multiplication ofthe bacteria,
allowing the immune system to cope with the infection.
Bacteriostatic antibiotics
These drugs preventthe production ofproteins
thatthe bacterialcellneeds in order to grow
and multiply, and the cell eventually dies.
Bactericidal antibiotics
These kill bacteria directly by causing the cell
wall to disintegrate; water is taken into the cell,
which expands and then bursts.
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