Fluoxetine with carbamazepine

The effects of buspirone are decreased when the drug is administered with fluoxetine Increased serum levels of buspirone occur if the drug is taken with erythromycin or itraconazole Should any of these combinations be required, the dosage of buspirone is decreased to 2.5 mg BID, and the patient is monitored closely. Venlafaxine blood levels increase with a risk of toxicity when administered witii MAOIs or cimetidine There is an increased risk of toxicity when trazodone is administered with the phenothiazines and decreased effectiveness of trazodone when it is administered with carbamazepine Increased serum digoxin levels have occurred when digoxin is administered with trazodone There is a risk for increased phenytoin levels when phenytoin is administered witii trazodone... 

Co-administration with carbamazepine may decrease plasma levels of risperidone > Co-administration with fluoxetine and paroxetine may increase plasma levels of risperidone... 

Fluoxetine Carbamazepine Diazepam Phenytoin Valproate Risk of toxicity of the object drugs with carbamazepine and valproate, interaction inconsistent Inhibition of metabolism of the object drugs... 

Carbamazepine Some, but not all, reports indicate that carbamazepine serum levels can be increased by fluoxetine and fluvoxamine. Toxicity may develop. Sertraline normally appears not to affect carbamazepine, but sertraline levels may be reduced by carbamazepine. Isolated cases of Par-kinson-like and serotonin syndrome have occurred with fluoxetine and carbamazepine, while an isolated case of pancytopenia has been reported with sertraline and carbamazepine. The metabolism of citalopram may be increased. 

Carbamazepine induces hepatic catabolic enzymes, with a consequent reduction in serum levels of antidepressants (mainly described with amitriptyline, desipramine, doxepin, imipramine, mianserin, and nortriptyline). A decrease in bupropion serum levels was also reported with carbamazepine. These effects were not observed with clomipramine. Fluoxetine and fluvoxamine inhibit the metabolism of carbamazepine and valproate (up to 30% and 50% increases in serum levels, respectively). No significant interaction has yet been found between paroxetine and carbamazepine or valproate. 

Recently, with the development of more advanced and sensitive analytical methods, studies on the fate of pharmaceuticals in WWTP have taken into account the analysis of pharmaceuticals sorbed into sludge (Table 4, and references therein). The antiseptics triclocarban and triclosan and the antibiotic ofloxacin have been reported in sludge at concentrations up to 441, 133, and 58 mg kgdw-1, respectively. Compounds such as the anti-inflammatory ibuprofen, the antiepileptic carbamazepine and the antidepressant fluoxetine have also frequently been reported though at lower levels (11,6 and 3 mg kgdw 1, respectively), whereas the (3-blockers were found at low... 

Drugs that may interact with halopehdol include anticholinergic agents, azole antifungal agents, carbamazepine, lithium, rifamycins, and fluoxetine. 

All SSRIs (e.g., Feonard et ah, 1997) and in particular fluoxetine, Fluvosamine and paroxetine are metabolized by hepatic cytochrome P450 enzymes. Therefore, it is important to be aware of the possibility that the therapeutic or toxic effects of other medications metabolized by the cytochrome P450 isoenzyme system can be increased. Substantial inhibition of these isoenzymes converts a normal metabolizer into a slow metabolizer with regard to this specific pathway. Inhibition of the hepatic oxidative isoenzymes has been associated with a reduction, to a varying extent, in the clearance of many therapeutic agents, including the TCAs, several neuroleptics, antiarrhythmics, theophy-lene, terfenadine, benzodiazepines, carbamazepine, and warfarin (for a complete list, see Nemeroff et ak, 1996). 

Loof et al. (1995) reported the use of carbamazepine (300-1200 mg/day, serum levels 10-11.5 pg/mL) in 28 children and adolescents with sexual abuse histories. By treatment end, 22 of 28 patients were asymptomatic of PTSD. The remaining six were significantly improved in all PTSD symptoms except for continued abuse-related nightmares. Half of this cohort had com-orbid ADHD, depression, ODD or polysubstance abuse and were treated with concomitant medications, e.g., methylphenidate, clonidine, sertraline, fluoxetine, or imipramine. 

Aripiprazole is hepatically metabolized, mainly by two cytochrome P450 enzymes CYP 2D6 and CYP 3A4. Therefore, dosage adjustments are necessary when this medication is given with other medications that either inhibit or induce these enzymes. For example, the dose of aripiprazole should be halved when this medication is given with ketoconazole, a CYP 3A4 inhibitor, or at least decreased when given with fluoxetine, a CYP 2D6 inhibitor. When aripiprazole is given with CYP 3A4 inducers such as carbamazepine, the dose should be doubled. 

Cardiac depressant effects may occur when verapamil or diltiazem is combined with a (p-adrenoceptor antagonoist or a cardiac glycoside. Nifedipine and verapamil are metabolised by cytochrome P-450 3A4. Inhibitors of this enzyme, e.g. HIV-protease inhibitors, cimetidine, fluoxetine, ketoconazole, erythromycin, will increase plasma levels and the dose should be carefully monitored. Conversely, enzyme inducers, e.g. carbamazepine, rifampicin, phenytoin, will decrease their plasma concentrations. 

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. 

Huntington s disease is an inherited disorder characterized by gradual onset of motor incoordination. The symptoms relate to movement disorders with jerk of the extremities, trunk, face, and neck. The progressive disease causes loss of memory (particularly recognition of friends and family) and is fatal63 This disease is treated only symptomatically. Drugs such as fluoxetine are used to treat depression and irritability. Carbamazepine also is useful in treating associated depression. 

Clinically important, potentially hazardous interactions with alprazolam, aprepitant, astemizole, atorvastatin, benzodiazepines, carbamazepine, chlordiazepoxide, cilostazol, clonazepam, clorazepate, colchicine, conivaptan, cyclosporine, dabigatran, dasatinib, diazepam, digoxin, dihydroergotamine, disopyramide, ergot alkaloids, fesoterodine, fluoxetine, flurazepam, fluvastatin, HMG-CoA reductase inhibitors, imatinib, ixabepilone, lapatinib, lopinavir, lorazepam, lovastatin, methylprednisolone, methysergide, midazolam, nilotinib, oxazepam, paroxetine, pimozide, pravastatin, prednisone, quazepam, repaglinide, rimonabant, rivaroxaban, sertraline, silodosin, simvastatin, solifenacin, temazepam, temsirolimus, tolvaptan, trabectedin, triazolam, warfarin, zidovudine... 

Clinically important, potentially hazardous interactions with caffeine, carbamazepine, cocoa, fluoxetine, guarana, insulin glulisine, risperidone, ritonavir, selenium, uracil/tegafur... 

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... 

Clinically important, potentially hazardous interactions with aprepitant, astemizole, carbamazepine, colchicine, cyclosporine, dihydroergotamine, ergot alkaloids, ergotamine, erythromycin, fluoxetine, fluvoxamine, methylprednisolone, methysergide, oral contraceptives, paroxetine, pimozide, prednisolone, rifampicin, sertraline, solifenacin, terfenadine, warfarin... 

After single-dose administration, the mean bioavailability of quetiapine is 9% with significant interindividual variation. If a CYP 3A4 inhibitor (e.g., cimetidine, ketoconazole, nefazodone, grapefruit juice, or erythromycin) is added to quetiapine, increased side effects (e.g., sedation or orthostasis) may occur. Fluoxetine may also decrease clearance of a medication such as quetiapine metabolized through CYP 3A4. However, with fluoxetine, it is the long-acting metabolite norfluoxetine, and not fluoxetine, that is the primary inhibitor of 3 A4 metabolism. If an enzyme inducer such as carbamazepine or St. lohn s wort is added to quetiapine, then decreased antipsychotic effects may occur. ... 

Because of the risk of seizures with higher clozapine tissue concentrations, inhibition interactions with clozapine are potentially significant. In particular, fluvoxamine has been reported to increase clozapine serum concentrations by an average of two- to threefold and up to fivefold. Fluoxetine and erythromycin may increase clozapine serum concentrations in some patients, but to a lesser degree. Mean clozapine serum concentrations are reported to be 32% lower in smokers compared with nonsmokers." Carbamazepine may also induce clozapine metabolism and lead to lower serum concentrations. ... 

Patients prescribed concomitant phenytoin or carbamazepine with fluoxetine may have increased anticonvulsant plasma concentrations and symptoms of toxicity. Markedly increased plasma concentrations of TCAs with resulting symptoms of toxicity have been reported in patients taking fluoxetine. 

Carbamazepine is metabolized to an active 10,11-epoxide metabolite, thus medications that inhibit 3A4 isoenzymes may result in carbamazepine toxicity (e.g., cimetidine, dUtiazem, erythromycin, fluoxetine, fluvoxamine, isoniazid, itraconazole, ketoconazole, nefa-zodone, propoxyphene, and verapamil). " When carbamazepine is combined with valproate, the carbamazepine dose should be reduced because valproate displaces carbamazepine from protein binding sites, thus increasing free levels." Combining clozapine and carbamazepine is not recommended because of the possibdity of bone marrow suppression with both agents. ... 

It is indicated in the treatment of depressive episodes associated with bipolar disorder. A combination of an antipsychotic drug and an antidepressant may be useful in some cases, especially in depressed psychotic patients, or in cases of agitated major depression with psychotic features. The first combination antipsychotic/antidepressant (olanza-pine/fluoxetine Symbyax) was recently FDA approved in the United States for treatment of depressive episodes associated with bipolar disorder. However, antidepressants and stimulants are unlikely to reduce apathy and withdrawal in schizophrenia, and they may induce clinical worsening in some cases. Adjunctive addition of lithium or an antimanic anticonvulsant, such as carbamazepine, may add benefit in some psychotic patients with prominent affective, aggressive, or resistant symptoms. 

Sedatives or anticonvulsants (e.g., carbamazepine, oxcarbazepine, phenobarbital, and pheny-toin, but not valproate) that induce CYPs (see Chapter S) can enhance the metabolism of antipsychotic and many other agents (including anticoagulants and oral contraceptives), sometimes with significant clinical consequences. Conversely, selective serotonin (5-HT) reuptake inhibitors including fluvoxamine, fluoxetine, paroxetine, venlafaxine, sertraline, and nefazodone (see Chapter 17) compete for these enzymes and can elevate circulating levels of neuroleptics. 

Spina E, Avenoso A, Pollicino AM, Caputi AP, Fazio A, Pisani F. Carbamazepine coadmin-isttation with fluoxetine or fluvoxamine. Ther DrugMonit (1993) 15, 247-50. 

The manufacturers of sertindole contraindicate the concurrent use of cimetidine, diltiazem, erythromycin, itraconazole, ketoco-nazole, terfenadine and verapamil because of an increased risk of cardiac arrhythmias. Carbamazepine and phenytoin reduce plasma sertindole levels whereas fluoxetine and paroxetine increase them. No clinically relevant interactions occur with alprazolam, antacids, food or tobacco smoking. 

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