Dexamethasone Carbamazepine

Drugs that may affect donepezil are CYP450 3A4 and 2D6 inhibitors (eg, ketoconazole, quinidine) and CYP450 3A4 and 2D6 inducers (eg, carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampin). Drugs that may be affected by donepezil include anticholinergics, cholinometics/cholinesterase inhibitors, NSAIDs. 

Concomitant medication with inducers of drug c/earance. Patients on rifampin should receive caspofungin 70 mg/day. Patients on nevirapine, efavirenz, carbamazepine, dexamethasone, or phenytoin may require an increase in dosage to caspofungin 70 mg/day. 

Drugs that may affect fosamprenavir include antacids, carbamazepine, delavirdine, dexamethasone, histamine H2-receptor antagonists, HMG-CoA reductase inhibitors,... 

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... 

Praziquantel is readily absorbed (80% in 24 hours) after oral administration, with serum concentrations being maximal in 1 to 3 hours the drug has a half-life of 0.8 to 1.5 hours. Its bioavailability is reduced by pheny-toin or carbamazepine and increased by cimetidine. Dexamethasone decreases plasma praziquantel levels by 50%. Praziquantel is excreted by the kidneys. 

Cortisone, dexamethasone. Barbiturates, carbamazepine. Reduced effect. 

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)... 

N/V/D, abcl pain, bleeding, fever, T QT Interactions T Effects W/ atazanavir, clar-itliromycin, erythromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfi-navir, ritonavir, saquinavir, telithromydn 1 effects W/ antacids, carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampicin, St. John s wort EMS Ding contains lactose, may cause D/abd discomfort in pts w/ lactose intolerance OD Sxs unknown symptomatic and supportive... 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

Delavirdine is extensively metabolized to inactive metabolites by the CYP3A and CYP2D6 enzymes. However, it also inhibits CYP3 A and thus inhibits its own metabolism. In addition to its interactions with other antiretroviral agents (see Table 49 1), delavirdine will result in increased levels of numerous agents (Table 49-3). Dose reduction of indinavir and saquinavir should be considered if they are administered concurrently with delavirdine. Delavirdine plasma concentrations are reduced in the presence of antacids, phenytoin, phenobarbital, carbamazepine, rifabutin, and rifampin concentrations are increased during coadministration with clarithromycin, fluoxetine, dexamethasone, and ketoconazole. 

If a drug is a substrate of CYP3A, coadministration with St. John s wort, a CYP3A inducer, can decrease the systemic exposure and effectiveness. St. John s wort may be listed in the labeling along with other known inducers, such as rifampin, rifabutin, rifapentin, dexamethasone, phenytoin, carbamazepine, or phenobarbital, as possibly decreasing plasma levels. 

Praziquantel Interactions of this drug are reported with carbamazepine, phenytoin, dexamethasone, and chloroquine.182... 

Figure 6.17 The classification of 42 drugs in the (solubility-dose ratio, apparent permeability) plane of the QBCS. The intersection of the dashed lines drawn at the cutoff points form the region of the borderline drugs. Key 1 acetyl salicylic acid 2 atenolol 3 caffeine 4 carbamazepine 5 chlorpheniramine 6 chlorothiazide 7 cimetidine 8 clonidine 9 corticosterone 10 desipramine 11 dexamethasone 12 diazepam 13 digoxin 14 diltiazem 15 disopyramide 16 furosemide 17 gancidovir 18 glycine 19 grizeofulvin 20 hydrochlorothiazide 21 hydrocortisone 22 ibuprofen 23 indomethacine 24 ketoprofen 25 mannitol 26 metoprolol 27 naproxen 28 panadiplon 29 phenytoin 30 piroxicam 31 propanolol 32 quinidine 33 ranitidine 34 salicylic acid 35 saquinavir 36 scopolamine 37 sulfasalazine 38 sulpiride 39 testosterone 40 theophylline 41 verapamil HC1 42 zidovudine.

Carbamazepine, dexamethasone, efavirenz, nevirapine, phenytoin, rifabutin, rifampin may decrease caspofungin levels... 

IFOSFAMIDE 1. ANTIBIOTICS-rifampicin 2. ANTICANCER AND IMMUNOMODULATING DRUGS - dexamethasone 3. ANTIDEPRESSANTS-St John s wort 4. ANTI EPILEPTICS -carbamazepine, phenytoin, phenobarbital t rate of biotransformation to 4-hydroxyifbsfamide, the active metabolite, but there is no change in AUC of 4-hydroxyifosfamide Due to t rate of metabolism and of clearance owing to induction of CYP3A4 and CYP2D6 Be aware - clinical significance may be minimal or none... 

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 atazanavir, carbamazepine, clarithromycin, dexamethasone, erythromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, phenobarbital, phenytoin, rifampicin, ritonavir, saquinavir, St John s wort... 

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 amprenavir, aprepitant, atazanavir, carbamazepine, chlorpheniramine, cimetidine, clarithromycin, clorazepate, CNS depressants, darunavir, delavirdine, dexamethasone, efavirenz, erythromycin, esomeprazole, fluconazole, fluoxetine, fosamprenavir, grapefruit juice, griseofulvin, imatinib, indinavir, itraconazole, ivermectin, ketoconazole, lopinavir, nelfinavir, nevirapine, phenobarbital, phenytoin, primidone, rifabutin, rifampin, ritonavir, roxithromycin, saquinavir, St John s wort, telithromycin, tipranavir... 

Carbamazepine, cholestyramine, dexamethasone, isoniazid, nafcillin, octreotide, phenobarbital, phenytoin, primidone, rifampin, sulfadimidine, sulfinpyrazone, ticlopidine Increase concentrations of CNIs... 

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