Contraindicated.safinamideSerious - Use Alternative (1)perphenazine decreases effects of safinamide by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Dopamine antagonists may decrease safinamide effects and exacerbate Parkinson disease symptoms.sageMinor (1)perphenazine and sage both increase sedation. Minor/Significance Unknown.salmeterolMonitor Closely (1)perphenazine increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.saquinavirSerious - Use Alternative (1)saquinavir, perphenazine. Either increases toxicity of the other by QTc interval. Avoid or Use Alternate Drug. Increased risk of PR or QT prolongation and cardiac arrhythmias.scopolamineMonitor Closely (3)scopolamine decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. scopolamine decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of scopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.scullcapMonitor Closely (1)perphenazine and scullcap both increase sedation. Use Caution/Monitor.secobarbitalMonitor Closely (1)secobarbital and perphenazine both increase sedation. Use Caution/Monitor.selegilineMonitor Closely (1)selegiline, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).selinexorSerious - Use Alternative (1)selinexor, perphenazine. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.selpercatinibMonitor Closely (1)selpercatinib increases toxicity of perphenazine by QTc interval. Use Caution/Monitor.serdexmethylphenidate/dexmethylphenidateMonitor Closely (1)perphenazine, serdexmethylphenidate/dexmethylphenidate. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.sertralineMonitor Closely (1)sertraline and perphenazine both increase QTc interval. Use Caution/Monitor.Minor (1)sertraline will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.sevofluraneMonitor Closely (2)sevoflurane and perphenazine both increase sedation. Use Caution/Monitor. sevoflurane and perphenazine both increase QTc interval. Use Caution/Monitor.shepherd's purseMonitor Closely (1)perphenazine and shepherd's purse both increase sedation. Use Caution/Monitor.siponimodMonitor Closely (1)siponimod and perphenazine both increase QTc interval. Use Caution/Monitor.smokingMonitor Closely (1)smoking decreases levels of perphenazine by increasing metabolism. Use Caution/Monitor. Interaction mainly seen w/chlorpromazine & thioridazine, but may occur w/other phenothiazines.sodium oxybateSerious - Use Alternative (1)perphenazine, sodium oxybate. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.sodium sulfate/?magnesium sulfate/potassium chlorideMonitor Closely (1)sodium sulfate/?magnesium sulfate/potassium chloride increases effects of perphenazine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of enhanced CNS depression when using higher dose of magnesium sulfate together with a CNS depressant.sodium sulfate/potassium sulfate/magnesium sulfateMonitor Closely (1)sodium sulfate/potassium sulfate/magnesium sulfate increases effects of perphenazine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of enhanced CNS depression when using higher dose of magnesium sulfate together with a CNS depressant.solifenacinMonitor Closely (4)solifenacin decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. solifenacin decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of solifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. solifenacin and perphenazine both increase QTc interval. Use Caution/Monitor.sorafenibMonitor Closely (1)sorafenib and perphenazine both increase QTc interval. Use Caution/Monitor.sotalolContraindicated (1)perphenazine and sotalol both increase QTc interval. Contraindicated.stiripentolMonitor Closely (1)stiripentol, perphenazine. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.sufentanilMonitor Closely (1)sufentanil and perphenazine both increase sedation. Use Caution/Monitor.sufentanil SLSerious - Use Alternative (1)sufentanil SL, perphenazine. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration may result in hypotension, profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.sulfamethoxazoleMonitor Closely (1)perphenazine and sulfamethoxazole both increase QTc interval. Modify Therapy/Monitor Closely.sumatriptanMonitor Closely (1)sumatriptan, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).sumatriptan intranasalMonitor Closely (1)sumatriptan intranasal, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).sunitinibMonitor Closely (1)sunitinib and perphenazine both increase QTc interval. Use Caution/Monitor.tacrolimusMonitor Closely (1)tacrolimus and perphenazine both increase QTc interval. Use Caution/Monitor.tamoxifenMonitor Closely (1)perphenazine decreases effects of tamoxifen by decreasing metabolism. Use Caution/Monitor. Inhibition of CYP2D6 metabolism to tamoxifen's active metabolite, endoxifen.tapentadolMonitor Closely (1)tapentadol and perphenazine both increase sedation. Use Caution/Monitor.telavancinMonitor Closely (1)perphenazine and telavancin both increase QTc interval. Modify Therapy/Monitor Closely.temazepamMonitor Closely (1)temazepam and perphenazine both increase sedation. Use Caution/Monitor.terbinafineMonitor Closely (1)terbinafine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Assess need to reduce dose of CYP2D6-metabolized drug.terbutalineMonitor Closely (1)perphenazine increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.tetrabenazineMonitor Closely (1)perphenazine and tetrabenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)tetrabenazine and perphenazine both increase QTc interval. Avoid or Use Alternate Drug.thioridazineMonitor Closely (2)perphenazine and thioridazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. perphenazine and thioridazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)perphenazine and thioridazine both increase QTc interval. Avoid or Use Alternate Drug. perphenazine will increase the level or effect of thioridazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.Minor (1)thioridazine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.thiothixeneMonitor Closely (2)perphenazine and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. perphenazine and thiothixene both increase sedation. Use Caution/Monitor.timololMonitor Closely (1)perphenazine will increase the level or effect of timolol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.tiotropiumMonitor Closely (3)tiotropium decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. tiotropium decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of tiotropium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.tipranavirMinor (1)tipranavir will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.tobacco useMonitor Closely (1)tobacco use decreases levels of perphenazine by increasing metabolism. Use Caution/Monitor. Interaction mainly seen w/chlorpromazine & thioridazine, but may occur w/other phenothiazines.tolterodineMonitor Closely (3)tolterodine decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. tolterodine decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of tolterodine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)perphenazine will increase the level or effect of tolterodine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.topiramateMonitor Closely (1)perphenazine and topiramate both increase sedation. Modify Therapy/Monitor Closely.tramadolMonitor Closely (1)tramadol and perphenazine both increase sedation. Use Caution/Monitor.trandolaprilMinor (1)perphenazine increases effects of trandolapril by unspecified interaction mechanism. Minor/Significance Unknown.tranylcypromineMonitor Closely (1)tranylcypromine, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).trazodoneMonitor Closely (1)perphenazine and trazodone both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and trazodone both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)trazodone, perphenazine. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive hypotensive effects. trazodone, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects.tretinoinSerious - Use Alternative (1)perphenazine, tretinoin. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.tretinoin topicalSerious - Use Alternative (1)perphenazine, tretinoin topical. Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. Increased phototoxicity.triazolamMonitor Closely (1)triazolam and perphenazine both increase sedation. Use Caution/Monitor.triclofosMonitor Closely (1)triclofos and perphenazine both increase sedation. Use Caution/Monitor.trifluoperazineMonitor Closely (2)perphenazine and trifluoperazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. perphenazine and trifluoperazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and trifluoperazine both increase QTc interval. Avoid or Use Alternate Drug.Minor (1)perphenazine will increase the level or effect of trifluoperazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.trihexyphenidylMonitor Closely (2)trihexyphenidyl decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of trihexyphenidyl by pharmacodynamic synergism. Use Caution/Monitor. Potential for additive anticholinergic effects.trimethoprimMonitor Closely (1)perphenazine and trimethoprim both increase QTc interval. Modify Therapy/Monitor Closely.trimipramineMonitor Closely (1)perphenazine and trimipramine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and trimipramine both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)trimipramine, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. trimipramine, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.triprolidineMonitor Closely (1)triprolidine and perphenazine both increase sedation. Use Caution/Monitor.tropisetronMonitor Closely (1)perphenazine and tropisetron both increase QTc interval. Modify Therapy/Monitor Closely.Minor (1)perphenazine will increase the level or effect of tropisetron by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.trospium chlorideMonitor Closely (3)trospium chloride decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. trospium chloride decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of trospium chloride by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.umeclidinium bromide/vilanterol inhaledSerious - Use Alternative (1)perphenazine increases toxicity of umeclidinium bromide/vilanterol inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.valbenazineMonitor Closely (1)valbenazine and perphenazine both increase QTc interval. Use Caution/Monitor.vecuroniumMonitor Closely (3)vecuronium decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. vecuronium decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of vecuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.venlafaxineMonitor Closely (2)venlafaxine, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). venlafaxine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.vilanterol/fluticasone furoate inhaledSerious - Use Alternative (1)perphenazine increases toxicity of vilanterol/fluticasone furoate inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.vilazodoneMonitor Closely (1)vilazodone, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).voriconazoleMonitor Closely (1)perphenazine and voriconazole both increase QTc interval. Modify Therapy/Monitor Closely.vorinostatMonitor Closely (1)vorinostat and perphenazine both increase QTc interval. Use Caution/Monitor.xylometazolineMonitor Closely (2)perphenazine, xylometazoline. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only. perphenazine increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.yohimbeSerious - Use Alternative (1)yohimbe decreases effects of perphenazine by pharmacodynamic antagonism. Contraindicated.yohimbineMonitor Closely (2)perphenazine, yohimbine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac