|
DRUG INTERACTIONS
Ifosfamide is a substrate for both CYP3A4 and CYP2B6.
Inducers of CYP3A4
CYP3A4 inducers (e.g., carbamazepine, phenytoin, fosphenytoin, phenobarbital, rifampin, St. John Wort) may increase the metabolism of ifosfamide to its active alkylating metabolites. CYP3A4 inducers may increase the formation of the neurotoxic/nephrotoxic ifosfamide metabolite, chloroacetaldehyde. Closely monitor patients taking ifosfamide with CYP3A4 inducers for toxicities and consider dose adjustment.
Inhibitors of CYP3A4
CYP3A4 inhibitors (e.g., ketoconazole, fluconazole, itraconazole, sorafenib, aprepitant, fosaprepitant, grapefruit, grapefruit juice) may decrease the metabolism of ifosfamide to its active alkylating metabolites, perhaps decreasing the effectiveness of ifosfamide treatment.
|
OVERDOSAGE
No specific antidote for IFEX is known.
Patients who receive an overdose should be closely monitored for the development of toxicities. Serious consequences of overdosage include manifestations of dose-dependent toxicities such as CNS toxicity, nephrotoxicity, myelosuppression, and mucositis [see Warnings and Precautions (5) ].
Management of overdosage would include general supportive measures to sustain the patient through any period of toxicity that might occur, including appropriate state-of-the-art treatment for any concurrent infection, myelosuppression, or other toxicity. Ifosfamide as well as ifosfamide metabolites are dialyzable.
Cystitis prophylaxis with mesna may be helpful in preventing or limiting urotoxic effects with overdose.
|
CONTRAINDICATIONS
IFEX is contraindicated in patients with:
-
•Known hypersensitivity to administration of ifosfamide.
-
•Urinary outflow obstruction.
|
REFERENCES
-
1.NIOSH Alert: Preventing occupational exposures to antineoplastic and other hazardous drugs in healthcare settings. 2004. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2004-165.
-
2.OSHA Technical Manual, TED 1-0.15A, Section VI: Chapter 2. Controlling occupational exposure to hazardous drugs. OSHA, 1999. http://www.osha.gov/dts/osta/otm/otm_vi/otm_vi_2.html.
-
3.American Society of Health-System Pharmacists. ASHP guidelines on handling hazardous drugs. Am J Health-Syst Pharm. 2006; 63:1172-1193.
-
4.Polovich M, White JM, Kelleher LO, (eds.) 2005. Chemotherapy and biotherapy guidelines and recommendations for practice. (2nd ed.) Pittsburgh, PA: Oncology Nursing Society.
|
|
|
-- advertisement --
|