ANTIBODY, MONOCLONAL
A
against these antigens help the body
to neutralize or destroy the invading
microorganisms. Antibodies may also be
formed in response to
vaccines,
thereby
giving immunity against certain infec-
tions. Antibodies are also known as
immunoglobulins.
Inappropriate or excessive formation
of antibodies may lead to illness, as in
an
allergy.
Antibodies against antigens in
organ transplants may result in rejection
of the transplanted organ. In some dis-
orders, antibodies are formed against
the body’s own tissues, resulting in an
autoimmune disorder.
antibody, monoclonal
An artificially produced
antibody
that
neutralizes only one specific
antigen
(foreign protein).
Monoclonal antibodies are produced
in
a
laboratory
by
stimulating
the
growth of large numbers of antibody-
producing
cells
that
are
genetically
identical. In effect, this process enables
antibodies to be tailor-made to react
with a particular antigen.
Monoclonal antibodies are used in
the study of human cells, hormones,
microorganisms, and in the develop-
ment of vaccines. They are also being
used in the diagnosis and treatment
of some forms of cancer. Genetically
engineered monoclonal antibodies are
designed to bind to the proteins on the
surface of certain cancer cells, marking
them out for destruction. The immune
system can then recognize these marked
cells and destroy them.
anticancer drugs
COMMON DRUGS
ALKYLATING AGENTS
•Chlorambucil
• Cyclophosphamide •Melphalan
antimetabolites
•Cytarabine •Fluorouracil
• Mercaptopurine •Methotrexate
cytotoxic a n tibio tics
•Doxorubicin
• Epirubicin
hormone treatments
•Anastrozole
• Bicalutamide •Cyproterone acetate
• Flutamide •Goserelin •Letrozole
• Leuprorelin •Medroxyprogesterone
• Megestrol •Tamoxifen
cytokines
•Interferon alfa •Interleukin 2
taxanes
•Docetaxel •Paclitaxel
others
•Carboplatin •Cisplatin •Etoposide
• Irinotecan •Rituximab
Drugs that are used to treat many forms
of
cancer.
Some tumours respond to
drug treatment better than others. Anti-
cancer drugs are particularly useful in
the treatment of
lymphomas, leukaemias,
breast cancer,
cancer of the testis (see
testis, cancer of),
and
prostate cancer.
HOW THEY WORK
Most anticancer drugs are cytotoxic (they
kill or damage cells or prevent them from
dividing). Cytotoxic drugs fall into sev-
eral classes, including alkylating agents,
antimetabolites, cytotoxic antibiotics, and
taxanes.
Cytokines
(proteins released by
cells in response to the presence of
harmful organisms) such as interferon
alpha bind to other cells, activating the
immune response (see
immune system).
In some cases, drug treatment is used
alone, but it is often combined with
surgery
or
radiotherapy.
Anticancer
HOW ANTICHOLINERGICS WORK
Acetylcholine combines with a receptor
on the cell’s surface. This interaction
stimulates activity in that cell (e.g.
contraction of a muscle fibre or
secretion of a fluid). Anticholinergic
drugs block the stimulatory action of
acetylcholine by combining with the
acetylcholine receptors. This action
produces, for example, muscle
relaxation (e.g. in the bladder,
intestine, and bronchi) and dries up
secretions in the mouth and lungs.
Anticholinergic drugs are used to treat
COPD and other conditions.
drugs are often given in combination
to maximize their effects. Treatment
with
cytotoxic
drugs
is
commonly
given by injection in short courses
repeated at intervals.
SIDE EFFECTS
Some cytotoxic drugs cause nausea and
vomiting and may cause hair loss and
increased
susceptibility
to
infection.
Others (such as tamoxifen for breast
cancer)
are
given
continuously
by
mouth for months or years and cause
few side effects.
anticholinergic drugs
COMMON DRUGS
AS bronchodilators
•Ipratropium bromide
• Oxitropium
FOR IRRITABLE BOWEL SYNDROME
•Atropine
• Dicycloverine •Hyoscine •Propantheline
for parkinsonism
•Benztropine
• Biperiden^Orphenadrine •Procyclidine
• Trihexyphenidyl (Benzhexol)
for urinary incontinence
•Flavoxate
• Oxybutynin •Propiverine •Tolterodine
• Trospium
A group of drugs, also called antimus-
carinics, that are used in the treatment
of
irritable bowel syndrome,
urinary incon-
tinence (see
incontinence, urinary),
COPD
(see
pulmonary disease, chronic obstructive),
Parkinson’s disease,
and
bradycardia
(an
abnormally slow heartbeat). Anticholin-
ergic drugs are used to dilate the pupil
before eye examination or surgery. They
may also be used as
premedication
before
general
anaesthesia
(see
anaesthesia,
general)
and to treat
motion sickness.
HOW THEY WORK
Anticholinergics block the effects of
acetylcholine,
a chemical released from
nerve endings in the parasympathetic
autonomic nervous system.
Acetylcholine
triggers activity in a number of cells. For
example, it stimulates muscle contrac-
tion, slows the heartbeat, and increases
secretions in the mouth and lungs.
SIDE EFFECTS
Possible side effects of anticholinergics
may include dry mouth, blurred vision,
urinary retention, and confusion.
anticoagulant drugs
COMMON DRUGS
• Certoparin
*
Dalteparin • Danaparoid
• Enoxaparin • Heparin •Nicoumalone
• Tinzaparin
*
Warfarin
A group of drugs used to treat and pre-
vent abnormal
blood clotting,
to treat
thrombosis,
and to prevent and treat
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