Itraconazole Dexamethasone

P-gp (ABCB1) Verapamil, digoxin, mitoxantrone, vinblastine, doxorubicin, losartan, talinolol, cortisol, dexamethasone, colchicine, loperamide, domperidone, indinavir, erythromycin, tetracycline, itraconazole, cyclosporine, methotrexate, amitryptyline, phenobarbital, morphine, cimetidine, and others... 

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,... 

Buspirone (BuSpar) [Anxiolytic] WARNING Closely monitor for worsening depression or emergence of suicidality Uses Short-term relief of anxiety Action Antianxiety antagonizes CNS serotonin receptors Dose Initial 7.5 mg PO bid T by 5 mg q2-3d to effect usual 20-30 mg/d max 60 mg/d Contra w/ MAOI Caution [B, /-] Avoid w/ severe hepatic/renal insuff Disp Tabs SE Drowsiness, dizziness, HA, N, EPS, serotonin synd, hostility, depression Notes No abuse potential or physical/psychologic d endence Interactions T Effects W/ erythromycin, clarithromycin, itraconazole, ketoconazole, diltiazem, verapamil, grapefruit juice effects W/ carbamazepine, rifampin, phenytoin, dexamethasone, phenobarbital, fluoxetine EMS T Sedation w/ concurrent EtOH use grapefruit juice may T risk of adverse effects OD May cause dizziness, miosis, N/V symptomatic and supportive... 

NA /D, abd pain, bleeding, fevCT, T QT Interactions t Effects W7 atazanavir, clarithromycin, CT5rthromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfi-navir, ritonavir, saquinavir, telithromycin X effects W7 antacids, carbamazqjine, dexamethasone, phenobarbital, phenytoin, rifampicin, St. John s wort EMS Drug contains lactose, may cause D/abd discomfort in pts w/ lactose intolerance OD Sxs unknown symptomatic and supportive... 

Although specific drug or food interactions with mifepristone have not been studied, on the basis of this drug s metabolism by CYP3A4, it is possible that ketoconazole, itraconazole, erythromycin, and grapefruit juice may inhibit its metabolism (increasing serum levels of mifepristone). Furthermore, rifampin, dexamethasone, St. John s wort, and certain anticonvulsants (e.g., phenytoin, phenobarbital, and carbamazepine) may induce mifepristone metabolism (lowering serum levels of mifepristone)... 

Phenytoin Cortisol, dexamethasone, digitoxin, itraconazole, theophylline... 

Itraconazole, given orally increased oral prednisolone concentrations by only 24% (481) but increased intravenous dexamethasone concentrations 3.3-fold and oral dexamethasone 3.7-fold (482). 

Varis T, Kivisto KT, Backman JT, Neuvonen PJ. The cytochrome P450 3A4 inhibitor itraconazole markedly increases the plasma concentrations of dexamethasone and enhances its adrenal-suppressant effect. Clin Pharmacol Ther 2000 68(5) 487-94. 

Since indinavir is a substrate as well as an inhibitor of CYP3 A4, numerous and complex drug interactions can occur as described above. Indinavir levels decrease with concurrent use of rifabutin, fluconazole, St. John s wort, and rifampin. Caution is advised with other 3 A4 inducers also, including phenobarbital, phenytoin, carbamezepine, and dexamethasone. Dose reduction of indinavir should be considered if coadministered with delavirdine, ketoconazole, or itraconazole, while an increase in the dose of indinavir is indicated if the drug is coadministered with efavirenz or rifabutin. 

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... 

Indinavir (IDV) Crixivan 100 mg, 200 mg, 333 mg, and 400 mg capsules Erythromycins, itraconazole, ketoconazole, fluconazole, tetracycline, dexamethasone... 

Itraconazole markedly increases both systemic exposure to dexamethasone and its effects. This interaction has been investigated in a randomized, double-blind, placebo-controlled, crossover study (94). Eight healthy volunteers took either oral itraconazole 200 mg od or placebo for 4 days. On day 4, each subject was given oral dexamethasone 4.5 mg or intravenous dexamethasone sodium phosphate 5.0 mg. Itraconazole reduced the systemic clearance of intravenous dexamethasone by 68%, and increased its AUC and prolonged its half-life more than three-fold the AUC of oral dexamethasone was increased nearly four-fold and its half-life nearly three-fold. Morning plasma cortisol concentrations at 47 and 71 hours after dexamethasone were significantly lower after itraconazole than placebo. 

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... 

Clinically important, potentially hazardous interactions with amlodipine, anisindione, anticoagulants, aprepitant, atorvastatin, barbiturates, benzodiazepines, butabarbital, carbamazepine, chlordiazepoxide, clarithromycin, clonazepam, dorazepate, corticosteroids, cyclosporine, dexamethasone, diazepam, dicumarol, erythromycin, ethotoin, felodipine, flurazepam, fluvastatin, fosphenytoin, isradipine, itraconazole, ketoconazole, lorazepam, lovastatin, mephenytoin, mephobarbital, midazolam, nicardipine, nifedipine, nimodipine, nisoldipine, oxazepam, pentobarbital, phenobarbital, pimozide, pravastatin, primidone, quazepam, rifampin, secobarbital, simvastatin, St John s wort, temazepam, warfarin... 

Clinically important, potentially hazardous interactions with atazanavir, carbamazepine, clarithromycin, CYP3A4 inhibitors, dexamethasone, grapefruit juice, indinavir, itraconazole, nefazodone, nelfinavir, phenobarbital, phenytoin, rifabutin, rifampin, rifapentin, ritonavir, saquinavir, St John s wort, telithromycin, voriconazole. The concomitant use of strong CYP3A4 inducers should be avoided... 

Clinically important, potentially hazardous interactions with amprenavir, aprepitant, bedomethasone, buprenorphine, calcium, chloramphenicol, cimetidine, dobazam, clorazepate, cyclosporine, cyproterone, darunavir, dasatinib, delavirdine, dexamethasone, diazoxide, disulfiram, dopamine, fesoterodine, fluconazole, flunisolide, fluoxetine, fosamprenavir, ginkgo biloba, hydrocortisone, imatinib, indinavir, influenza vaccines, isoniazid, isradipine, itraconazole, lacosamide, lapatinib, lopinavir, meperidine, methylprednisolone, midazolam, mivacurium, nelfinavir, nilotinib, nilutamide, phenylbutazone, piracetam, posaconazole, prednisolone, prednisone, primrose, ritonavir, rivaroxaban, sage, saquinavir, solifenacin, St John s wort, sucralfate, telithromycin, temsirolimus, teniposide, ticlopidine, tizanidine, tolvaptan, triamcinolone, uracil/tegafur, vigabatrin... 

Clinically important, potentially hazardous interactions with amiodarone, amprenavir, anisindione, antacids, anticoagulants, aprepitant, atazanavir, atovaquone, beclomethasone, buprenorphine, corticosteroids, cortisone, cyclosporine, cyproterone, dabigatran, dapsone, darunavir, delavirdine, dexamethasone, dicumarol, digoxin, eszopiclone, flunisolide, fosamprenavir, gadoxetate, gestrinone, halothane, imatinib, isoniazid, itraconazole, ketoconazole, lapatinib, lorcainide, methylprednisolone, midazolam, nelfinavir, nifedipine, oral contraceptives, phenylbutazone, prednisone, protease inhibitors, pyrazinamide, ramelteon, ritonavir, saquinavir, solifenacin, sunitinib, tacrolimus, telithromycin, temsirolimus, tipranavir, tolvaptan, trabectedin, triamcinolone, triazolam, voriconazole, warfarin, zaleplon... 

There is some evidence to surest that itraconazole can increase the ieveis and/or effects of inhaled budesonide, the active metab-oiite of ciclesonide, deflazacort, dexamethasone and methylpred-nisoione, and, to a lesser extent, prednisolone and prednisone. A few case reports describe the development of secondary Cnsh-ing s syndrome in patients taking itraconazole and bndesonide, fluticasone and deflazacort... 

A study in 8 healthy subjects found that itraconazole 200 mg daily for 4 days increased the AUC, peak plasma level, and elimination half-life of a single 4.5-mg dose of dexamethasone by 3.7-, 1.7-, and 2.8-fold, respectively. In another phase of the study itraconazole decreased the systemic clearance of intravenous dexamethasone 5 mg by 68% and increased the AUC and elimination half-life 3.3- and 3.2-fold, respectively. The adrenal-suppressant effects of dexamethasone were enhanced by itraconazole. ... 

Bortezomib In a retrospective medical record review of six adults with relapsed multiple myeloma who received intravenous bortezomib + oral dexamethasone, three who also took itraconazole had new or worsening peripheral neuropathy and grade 4 thrombocytopenia [13 ]. One patient who took lansoprazole alone and two who did not take itraconazole or lansoprazole had no such reactions. The authors noted that itraconazole inhibits CYP3A4 and lansoprazole inhibits CYP2C19. 

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