Paroxetine Aripiprazole

Risperidone Aripiprazole 2D6 > 3A4 2D6, 3A4 Carbamazepine and phenytoin topiramate hypericum (St. John s Wort). Paroxetine, fluoxetine, sertraline (high dose) grapefruit juice 2D6 or 3A4 substrates acting as competitive inhibitors. 

Concomitant use with potential CYP2D6 inhibitors - During coadministration of potential CYP2D6 inhibitors such as quinidine, fluoxetine, or paroxetine with aripiprazole, reduce the aripiprazole dose to at least one-half of its normal dose. 

Fluvoxamine (Luvox) Nefazodone (Serzone) Paroxetine (Paxil) CLOZAPINE, THIORIDAZINE, HALOPERIDOL, OLANZAPINE, THIOTHIXENE PHENOTHIAZINES, Risperidone, Aripiprazole Clozapine, Quetiapine, Ziprasidone QUETIAPINE, Clozapine, Ziprasidone ... 

Fluoxetine and probably paroxetine may cause clinically significant increases in aripiprazole levels. The concurrent use of aripiprazole with SSRIs or venlafaxine has led to adverse effects such as the neuroleptic malignant syndrome and extrapyramidal symptoms. 

The manufacturers suggest that potent inhibitors of CYP2D6, such as fluoxetine and paroxetine would be expected to increase aripiprazole levels, and they recommend that the dose of aripiprazole should be halved if these drugs are given. The UK manufacturer suggests that weaker inhibitors of this isoenzyme (they name escitalopram) would only be expected to cause modest increases in aripiprazole levels, and therefore no dosage adjustment would expected to be required. ... 

The concurrent use of aripiprazole and SSRIs can be useful, but it is important to remember to adjust the dose if paroxetine or fluoxetine are started or stopped, and be aware that, rarely, adverse effects such as extrapyramidal symptoms and the neuroleptic malignant syndrome may develop. 

Drug-drug interactions SSRIs Aripiprazole had no effects on the pharmacokinetics of escitalopram, fluoxetine, paroxetine, sertraline, or venlafaxine either in healthy subjects ( =63) or in patients with major depressive disorder ( =498) [69. Point estimates for mean plasma concentration ratios indicated no substantial effect of aripiprazole on any antidepressant escitalopram 0.97 (0.91-1.03), fluoxetine 1.18 (1.05-1.32), paroxetine 0.73 (0.60-0.89), sertraline 0.96 (0.89-1.04), or venlafaxine 0.97 (0.89-1.05). 

Metabolism A 6-month, retrospective chart review compared patients on aripiprazole alone to aripiprazole and an SSRI (citalopram, fluoxetine, paroxetine, sertraline, venlafaxine) or aripiprazole and bupropion [92 ]. Only the combination of aripiprazole and an SSRI had statistically significant weight gain, thus it was hypothesised that in the presence of high serotonergic activity, aripiprazole acts as an antagonist at the 5-HT2c receptor. 

Drug-drug interactions The pharmacokinetics of aripiprazole, with and without coadministration of SSRIs, were compared according to CYP2D6 genotypes [93. Paroxetine decreased systemic clearance of aripiprazole by 58% and 23% in CYP2D6 extensive metaboUzers and intermediate metabolizers, respectively, while fluvoxamine had no effect... 

Azuma J, Hasunuma T, Kubo M, Miyatake M, Koue T, Higashi K, et al. The relationship between clinical pharmacokinetics of aripiprazole and CYP2D6 genetic polymorphism effects of CYP enzyme inhibition by coadministration of paroxetine or fluvoxamine. Eur J Clin Pharmacol 2012 68(l) 29-/37. 

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