Hypersensitivity, patients with low blood pressure, dehydration, pregnancy, nursing mothers, patients with renal or hepatic impairment, children and elderly over 70 years.
Special precautions:
Patients should be well hydrated & kept supine during amifostine infusion which should be given within15 minutes. Prolonged infusion causes greater side effects .
Antihypertensive drugs should be stopped 24 before infusion.
BP should be monitored.
Antiemetics may be administered before infusion epecially when emetogenic drugs are used.
Dosages/ Overdosage Etc:
Indication-
As a cyoprotective agent in chemotherapy
Dosage-
The recommended starting dose for adults is 910mg/m2 administered once daily as an IV infusion over 15 minutes starting within 30 minutes prior to chemotherapy infusions. Blood pressure should be monitored during infusion of amifostine.
Pharmacology/ Pharmacokinetics:
Pharmacology-
Amifostine is a prodrug, and requires conversion by alkaline phosphates to the active metabolite Amifostine shows a much greater protective action in the normal cells because of their higher pH and the higher activity to alkaline phosphates in their cell membranes. This allows greater conversion of amifostine into the active metabloite.
Pharmacokinetics:
During a 15-minute infusion of 910 mg/m2, the peak plasma concntration of amifostine is approx 200 micromol.L.
The elimination half-life is less than 10 minutes. Less than 4% of amifostine and its metabolites are excreted in the urine.