Ifosfamide Dexamethasone

DEXAMETHASONE IFOSFAMIDE t rate of biotransformation to 4-hydroxyifosfamide, the active metabolite, but no change in AUC of 4-hydroxyifosfamide Due to t rate of metabolism and clearance due to induction of CYP3A4 and CYP2D6 Be aware - the clinical significance may be minimal or none... 

Biagi, J.J., Herbert, K.E., Smith, C., Abdi, E., Leahy, M., Falkson, C., Wolf, M Januszewicz, H., Seymour, J.F., Richards, K., Matthews, J.P., Dale, B., and Prince, H.M. (2005) A phase II study of dexamethasone, ifosfamide, cisplatin and etoposide (DICE) as salvage chemotherapy for patients with relapsed and refractory lymphoma. Leukemia and Lymphoma, 46, 197-206. 

Aflatoxin Bl, bupropion, cyclophosphamide, dexamethasone, etoposide, ifosfamide, midazolam, phenobarbital, propofol, rifampin, teitiposide, thiotepa, vitamin D, xenobiotics Amitriptyhne, carisoprodol,... 

Trabectedin is licensed for the treatment of advanced soft-tissue sarcoma when treatment with anthracyclines and ifosfamide has failed or is contraindicated. It is administered by intravenous infusion. Trabectedin may cause hepatobiliary disorders and for this reason hepatic function should be evaluated before starting treatment and during treatment. Dexamethasone is administered intravenously with trabectedin for its anti-emetic and hepatoprotective effects. As with other antineoplastic drugs, trabectedin causes nausea and vomiting and bone-marrow suppression as side-effects. 

Aprepitant may be affected by paroxetine, CYP2C9 substrates (eg, phenytoin, tolbutamide, warfarin), CYP3A4 substrates (eg, alprazolam, cisapride, dexamethasone, docetaxel, etoposide, ifosfamide, imatinib, irinotecan, methylprednisolone, midazolam, paclitaxel, pimozide, triazolam, vinblastine, vincristine, vinorelbine), and oral contraceptives. 

Aprepitant (Emend) [Centrally Acting Antiemetic] Uses Pre-vents N/V assoc w/ emetogenic CA chemo (eg, cisplatin) (use in combo w/ other antiemetics) Action Substance P/neurokinin l(NKi) receptor antagonist Dose 125 mg PO day 1, 1 h before chemo, then 80 mg PO qAM days 2 3 Caution [B, /-] Contra Use w/ pimozide, Disp Caps SE Fatigue, asthenia, hiccups Interactions T Effects W/ clarithromycin, diltiazem, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, troleandomycin T effects OF alprazolam, astem-izole, cisapride, dexamethasone, methylprednisolone, midazolam, pimozide, terfe-nadine, triazolam, chemo agents, eg, docetaxel, etoposide, ifosfamide, imatinib, irinotecan, paclitaxel, vinblastine, vincristine, vinorelbine i effects W/ paroxetine,... 

Clinically important, potentially hazardous interactions with alprazolam, astemizole, carbamazepine, cisapride, clarithromycin, dexamethasone, diltiazem, docetaxel, ifosfamide, imatinib, irinotecan, itraconazole, ketoconazole, methylprednisolone, midazolam, nefazodone, oral contraceptives, paroxetine, phenytoin, pimozide, rifampin, ritonavir, terfenadine, tolbutamide, trabectedin, troleandomycin, vinblastine, vincristine, warfarin... 

There is limited and conflicting evidence on the effect of prednisone and prednisolone on the metabolic activation of cyclophosphamide. Synergistic increases in enzyme induction may occur if cyclophosphamide is given with dexamethasone. Dexamethasone does not appear to alter ifosfamide metabolism. 

In rats, dexamethasone pretreatment had no net impaet on the fraetion of ifosfamide undergoing aetivation. Similarly, in a elinieal study, ifosfamide metabolism was no different when patients were given dexamethasone 4 mg every 8 hours with ifosfamide for 3 days than when they received ifosfamide alone. ... 

The documentation is very limited. It appears that dexamethasone does not have any appreciable effeet on the metabolism of ifosfamide. The information on cyclophosphamide is eonflicting, and the elinieal importanee of any changes remains to be established. However, it should be noted that... 

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