MedicalToday

Pharmacology.
Ifosfamide is a structural analogue of the alkylating agent cyclophosphamide (CTX). The rate of hepatic conversion of ifosfamide to the active metabolite 4-hydroxyifosfamide is slightly slower than with CTX, although formation of the bladder toxin acrolein is not reduced. The ultimate metabolite ifosforamide mustard cross-links DNA to impair cell division. The drug is always given with mesna to prevent urotoxicity. Although labeled for use in refractory testicular cancer, ifosfamide also has useful activity against soft tissue sarcoma, malignant lymphoma, and small cell lung cancer. Ifosfamide is cell-cycle phase nonspecific.

Pharmacology.

Fluoxetine is a bicyclic antidepressant that is a selective and potent inhibitor of presynaptic reuptake of serotonin (an SSRI). It does not affect re-uptake of norepinephrine or dopamine and has a relative lack of affinity for muscarinic, histamine,

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1- and

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2-adrenergic, and serotonin receptors.

Administration and Adult Dosage.

Pharmacology.
Enalapril is a prodrug that is rapidly converted to its active metabolite, enalaprilat, by ester hydrolysis in the liver. Enalaprilat is a competitive ACE inhibitor. It also reduces serum aldosterone, leading to decreased sodium retention, potentiates the vasodilator kallikrein-kinin system, and can alter prostanoid metabolism, inhibit the sympathetic nervous system, and inhibit the tissue renin-angiotensin system. The net effect is reduction in total peripheral resistance and blood pressure in hypertensive patients, especially those with high pretreatment plasma renin activity and increased renal plasma flow, and reduction of elevated afterload in patients with CHF.

Pharmacology.
Cyclophosphamide is inactive in vitro and must be enzymatically activated in the liver to yield active alkylating compounds and toxic metabolites. Cell-cycle phase nonspecific.

Administration and Adult Dosage.
IV or PO alone or in combination regimens 250-500 mg/m2 q 3-4 weeks. IV (usually) or PO in high-dose intermittent regimens (including bone marrow transplant) maximum of 40-50 mg/kg given once or over 2-5 days, repeat q 2-4 weeks-these doses are not well tolerated orally.

Pharmacology.

Codeine is 3-methoxymorphine, a phenanthrene opioid with very low affinity for opioid receptors. Its analgesic activity appears to result from conversion to morphine. Poor metabolizers of debrisoquine/sparteine (approximately 7% of the Caucasian population) cannot convert appreciable amounts of codeine to morphine or obtain analgesia from codeine but are still subject to the same adverse effects.

Administration and Adult Dosage.

PO, SC, or IM for analgesia 15-60 mg q 4-6 hr.