Paclitaxel Dexamethasone

DEXAMETHASONE PACLITAXEL X plasma concentration s of paditaxel and X efficacy of paditaxel Due to induction of hepatic metabolism of paditaxel by the CYP isoenzymes Monitor for clinical efficacy and need to T dose if inadequate response is due to interaction... 

Paclitaxel Peripheral neuropathy (DLT), nausea/vomiting, alopecia, hypersensitivity reactions Use caution with any elevation in AST (SGOT). Give proper dosing for liver dysfunction. Premedicate dexamethasone, diphenhydramine, and cimetidine. 

Both omeprazole, a proton pump inhibitor and paclitaxel, a taxane cytotoxic may cause nausea and vomiting as side-effects. Prednisolone, as with other corticosteroids, does not cause nausea and vomiting. Corticosteroids such as dexamethasone are administered to relieve nausea and vomiting, particularly that associated with chemotherapy. 

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. 

Both drugs are highly lipid soluble and as such are prepared and administered in dilutants (paclitaxel in Cremophor EL and docetaxel in polysorbate 80). Both medications are normally administered with dexamethasone, H, and H2 antagonists as premedications to decrease the incidence of the acute hypersensitivity reaction (HSR) (dyspnea with bronchospasm, urticaria, and hypotension) that has been observed to occur... 

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,... 

Acyclovir Erythromycin Ivermectin Itraconazole Rifampin Actinomycin D Daunorubicin Doxorubicin Docetaxel Epirubicin Etoposide Imatinib Irinotecan Paclitaxel Vinblastine Vincristine Amprenavir Indinavir Nelfinavir Ritonavir Saquinavir Cyclosporine A Tacrolimus Digoxin Quinidine Verapamil Diltiazem Aldosterone Cortisol Corticosterone Dexamethasone Hydrocortisone Cyclosporine Metkephamid Enkephalin... 

The other toxicities of carboplatin are generally milder and better tolerated than those of cisplatin. Nausea and vomiting, though frequent, is less severe, shorter in duration, and more easily controlled with standard antiemetics (for example compazine, dexamethasone, lorazepam) than that following cisplatin treatment. Renal impairment is infrequent, though alopecia is common, especially with the paclitaxel-containing combinations. Neu-... 

Drugs that are known to be substrates of P-gp include antihistamines (e.g. terfenadine), digoxin, ciclosporin, hydrocortisone and other steroids and drugs used in chemotherapy (e.g. paclitaxel, vinblastine). Ciclosporin, in addition to being a substrate of P-gp, is also an inhibitor of P-gp. Drugs known to induce P-gp include morphine, dexamethasone, phenobarbital, rifampin and St John s wort. Inhibitors of P-gp include amiodarone, amitriptyline, atorvastatin, chlorpromazine, ciclosporin, erythromycin, fluphenazine, haloperidol, quinidine, ritonavir and verapamil,... 

Premedication, consisting of dexamethasone 20 mg intravenously, 12 and 6 hours before the infusion, and diphenhydramine 50 mg and cimetidine 300 mg, intravenously 30 minutes before the infusion, are now routinely given before patients are treated with paclitaxel, and this, as well as a recommended infusion time of 3 hours, has reduced the incidence and severity of hypersensitivity reactions. A single dose of dexamethasone 16 mg given 30 minutes before paclitaxel was effective in preventing hypersensitivity reactions in 43 patients (38) however, whether a single dose of a glucocorticoid is sufficient for prophylaxis is controversial. 

Parikh B, Khanolkar S, Advani SH, Dhabhar B, Chandra M. Safety profile of single-dose dexamethasone premedication for paclitaxel. J Clin Oncol 1996 14(7) 2189-90. 

C It is recommended that all patients receiving paclitaxel receive pretreatment to reduce the risk and severity of hypersensitivity reactions. The preferred regimen includes a combination of a corticosteroid (such as dexamethasone), an antihistamine (diphenhydramine or equivalent), and an Hj antagonist (such as cimetidine or ranitidine). Omeprazole and other PPIs will not block Hj-receptor sites and do not provide protection against hypersensitivity reactions. 

Prepare and administer using glass or non-PVC IV bags and tubing Premedicate patients to prevent hypersensitivity reactions dexamethasone 20 mg IV or orally 12 hours and 6 hours prior to paclitaxel, and diphenhydramine 50 mg IV 30 minutes prior to paclitaxel, and ranitidine 50 mg IV or cimetidine 300 mg IV 30 minutes prior to paclitaxel Reduce dose in patients with elevated total bilirubin (>1.5 mg/dL) and/or elevated transaminases (guidelines not well established)... 

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