Pharmacology for Dentistry

Chemotherapy of Malignancy 373

After oral administration it is well
absorbed. It is a prodrug and converted in
the blood and liver to its active form
(metabolites) namely hydroxyphosphamide
and aldophosphamide. It is excreted in urine.

Adverse effects include nausea,
vomiting, visual blurring, facial burning
with IV administration, teratogenic effect,
haemorrhagic cystitis, bone marrow
depression, hyponatremia, sterility,
inappropriate secretion of ADH, alopecia
and increased skin pigmentation.

It is indicated in leukaemias,
lymphogranulomatosis, lymphosarcoma,
reticulum cell sarcoma, Hodgkin’s disease,
multiple myeloma, retinoblastoma,
carcinoma of the breast, adenocarcinoma
of the ovary, inoperable solid malignancies.
It is used in combination with surgery,
radiation and other therapeutic measures.

MESNA

Cyclophosphamide and ifosfamide
cause urothelial toxicity (haemorrhagic
cystitis) which is caused by metabolite ‘ac-
rolein’. Mesna reacts with this metabo-
lites in the urinary tract to prevent toxic-
ity and is used in prevention of toxicity
to the urinary passage caused by
oxazaphosphorins e.g. ifosfamide and
cyclophosphamide.

CHLORAMBUCIL

It is a slow acting alkylating agent.
After oral administration, it shows
adequate and reliable absorption and
almost completely metabolised.

It is indicated in chronic lymphocytic
leukaemia (drug of choice), primary

(Waldenstrom’s) macroglobulinaemia,

advanced ovarian adenocarcinoma, breast

cancer, certain forms of nonHodgkin’s

lymphoma and Hodgkin’s disease.

Adverse effects include nausea,

vomiting, pulmonary fibrosis, dermatitis,

hepatotoxicity, seizures, amenorrhoea,

azoospermia, peripheral neuropathy and

bone marrow depression.

BUSULFAN

After oral administration, it is well

absorbed and excreted in urine as

methanesulfonic acid. It is mainly used in

chronic myeloid leukaemia, polycythemia

vera, essential thrombocythemia and

myelofibrosis.

Adverse effects include, thrombocy-

topenia, amenorrhoea, azoospermia, skin

pigmentation, nausea, vomiting, cataract,

gynaecomastia, pulmonary fibrosis and

hyperuricaemia.

LOMUSTINE

It is rapidly absorbed from GIT after

oral administration and is completely and

rapidly metabolised. It is indicated in

Hodgkin’s disease, brain tumour, lung

carcinoma, solid tumours and malignant

melanoma.

Adverse effects include nausea, vom-

iting, delayed bone marrow depression

(four to six weeks), leucopenia, thrombocy-

topenia and pulmonary fibrosis.

THIO-TEPA

Chemically it is ethylenimine and

because of high toxicity, it is rarely used.