Pharmacology for Dentistry

Vaccines, Sera and Other Immunological Agents 447

negative mothers after child birth, abortion
beyond 13 weeks gestation, antepartum
prophylaxis at 26 to 28 weeks gestation.

Dosage:

Adults: Prophylaxis after delivery, abor-
tion, amniocentesis: 300 mcg IM within 72
hours. Massive transplacental haemor-
rhage: 25 mcg/ml of foetal erythrocytes.

HISTAGLOBULIN

Histaglobulin is a lyophilised prepa-
ration of histamine (as histamine dihydro-
chloride) coupled with human normal
immunoglobulin.

Histaglobulin is thoroughly screened for
hepatitis B surface antigen and anti HIV
using third generation technique RIA and
ELISA and is found to be non-reactive.

As histamine by itself is not an
antigenic molecule, it is conjugated with
globular protein to form a complete antigen
wherein histamine acts as hapten when
injected into a living body, forming
antibodies to the hapten histamine
complex. Antibodies thus formed increase
the histamine binding capacity of serum.
It has been demonstrated that the histamine
binding capacity of normal plasma is 20
percent to 30 percent, whereas it is only
zero to five percent in allergic patients.

Adverse effects include nausea,
vomiting and vasodilatation in the facial
area.

It is indicated in bronchial asthma,
migraine, urticaria, eczema, allergic
rhinitis, pruritus, neurodermatitis, atopic
dermatitis and other allergic disorders.

IMMUNOSUPPRESSANTS

These are the agents used to suppress the

immunity. The drugs like azathioprine and

cyclosporin A are used chiefly to prevent

rejection in organ transplantation. They are

also used for treatment of autoimmune

disease.

AZATHIOPRINE (IMURAN)

It is a purine antagonist, immunosup-

pressant drug which suppresses cell medi-

ated immunity. It acts by inhibiting DNA

synthesis and hence prevents proliferation

of T-lymphocytes.

After administration in body it is

converted to mercaptopurine.

Adverse effects include skin rash, bone

marrow depression, GI disturbances and

hepatotoxicity.

It is indicated in renal transplantation,

severe active rheumatoid arthritis

unresponsive to other therapy, certain

autoimmune diseases, chronic active

hepatitis, idiopathic thrombocytopenic

purpura and acquired haemolytic

anaemia.

Dosage:

Renal transplantation: Initially 3 to 5 mg/

kg/day followed by 1 to 3 mg/kg/day as

maintenance dose.

Rheumatoid arthritis: Initially 1 mg/kg as

a single dose; if required increase after six to

eight weeks by 0.5 mg/kg/day at four weeks

intervals up to a maximum of 2.5 mg/kg/day.

CYCLOSPORINE A (SANDIMMUN)

It inhibits early cellular response to

antigenic and regulatory stimuli, mainly in