Procarbazine

Procarbazine

Procarbazine hydrochloride, a methylhydrazine derivative withmonoamine oxidase inhibitor (MAOI) properties, is used to treat Hodgkin’s disease and primary and metastatic brain tumors.

Pharmacokinetics

After oral administration, procarbazine is well absorbed. It readily crosses the blood-brain barrier and is well distributed into CSF.

Metabolism and excretion

Procarbazine is metabolized rapidly in the liver and must be acti-vated metabolically by microsomal enzymes. It’s excreted in urine, primarily as metabolites. Respiratory excretion of the drug occurs as methane and carbon dioxide gas.

Pharmacodynamics

An inert drug, procarbazine must be activated metabolically in the liver before it can produce various cell changes. It can cause chro-mosomal damage, suppress mitosis, and inhibit DNA, RNA, and protein synthesis. Cancer cells can quickly develop resistance to procarbazine.

Pharmacotherapeutics

Procarbazine is used in the treatment of Hodgkin’s disease, lym-phoma, and brain cancer.

Drug interactions

Interactions with procarbazine can be significant.

·                 It produces an additive effect when administered with CNS de-pressants.

·                 Taken with meperidine, it may result in severe hypotension and death.

Mirroring MAO

Because of procarbazine’s MAOI properties, hypertensive reac-tions may occur when it’s administered concurrently with sympa-thomimetics, antidepressants, and tyramine-rich foods. (See Ad-verse reactions to procarbazine.)