affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.marijuanamarijuana will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.metyraponeperphenazine decreases effects of metyrapone by unspecified interaction mechanism. Minor/Significance Unknown.metyrosinemetyrosine increases toxicity of perphenazine by pharmacodynamic synergism. Minor/Significance Unknown. Increased extrapyramidal symptoms.moexiprilperphenazine increases effects of moexipril by unspecified interaction mechanism. Minor/Significance Unknown.nilotinibnilotinib will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.nortriptylinenortriptyline, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects.nortriptyline, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.oxybutyninoxybutynin increases toxicity of perphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxybutynin topicaloxybutynin topical increases toxicity of perphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxybutynin transdermaloxybutynin transdermal increases toxicity of perphenazine by unspecified interaction mechanism. Minor/Significance Unknown.oxycodoneperphenazine decreases effects of oxycodone by decreasing metabolism. Minor/Significance Unknown. Decreased conversion of oxycodone to active metabolite morphine.parecoxibparecoxib will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.perhexilineperphenazine will increase the level or effect of perhexiline by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.perindoprilperphenazine increases effects of perindopril by unspecified interaction mechanism. Minor/Significance Unknown.prochlorperazineperphenazine will increase the level or effect of prochlorperazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.promazineperphenazine will increase the level or effect of promazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.promethazineperphenazine will increase the level or effect of promethazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.protriptylineprotriptyline, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects.protriptyline, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.pyrimethaminepyrimethamine increases levels of perphenazine by decreasing metabolism. Minor/Significance Unknown.quinacrinequinacrine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.quinaprilperphenazine increases effects of quinapril by unspecified interaction mechanism. Minor/Significance Unknown.ramiprilperphenazine increases effects of ramipril by unspecified interaction mechanism. Minor/Significance Unknown.ranolazineranolazine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.risperidoneperphenazine will increase the level or effect of risperidone by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.ritonavirritonavir will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.sageperphenazine and sage both increase sedation. Minor/Significance Unknown.sertralinesertraline will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.thioridazinethioridazine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.tipranavirtipranavir will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.tolterodineperphenazine will increase the level or effect of tolterodine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.trandolaprilperphenazine increases effects of trandolapril by unspecified interaction mechanism. Minor/Significance Unknown.trazodonetrazodone, 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.trifluoperazineperphenazine will increase the level or effect of trifluoperazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.trimipraminetrimipramine, 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.tropisetronperphenazine will increase the level or effect of tropisetron by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.abirateroneMonitor Closely (1)abiraterone increases levels of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Avoid coadministration of abiraterone with substrates of CYP2D6. If alternative therapy cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate.abobotulinumtoxinAMonitor Closely (1)abobotulinumtoxinA increases effects of perphenazine by pharmacodynamic synergism. Use Caution/Monitor. Use of anticholinergic drugs after administration of botulinum toxin-containing products may potentiate systemic anticholinergic effects.aclidiniumMonitor Closely (2)aclidinium decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of aclidinium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.acrivastineMonitor Closely (1)acrivastine and perphenazine both increase sedation. Use Caution/Monitor.adagrasibSerious - Use Alternative (1)adagrasib, perphenazine. Either increases effects of the other by QTc interval. Avoid or Use Alternate Drug. Each drug prolongs the QTc interval, which may increased the risk of Torsade de pointes, other serious arryhthmias, and sudden death. If coadministration unavoidable, more frequent monitoring is recommended for such patients.albiglutideMonitor Closely (1)perphenazine, albiglutide. Other (see comment). Use Caution/Monitor. Comment: Phenothiazines may increase or decrease glucose levels, monitor therapy closely when these agents are concurrently administered.albuterolMonitor Closely (1)perphenazine increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.alfentanilMonitor Closely (1)alfentanil and perphenazine both increase sedation. Use Caution/Monitor.alfuzosinMonitor Closely (2)perphenazine and alfuzosin both increase QTc interval. Use Caution/Monitor. alfuzosin and perphenazine both increase QTc interval. Use Caution/Monitor.almotriptanMonitor Closely (1)almotriptan, 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).alprazolamMonitor Closely (1)alprazolam and perphenazine both increase sedation. Use Caution/Monitor.amifampridineMonitor Closely (1)perphenazine increases toxicity of amifampridine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Amifampridine can cause seizures. Coadministration with drugs that lower seizure threshold may increase this risk.aminolevulinic acid oralSerious - Use Alternative (1)aminolevulinic acid oral, perphenazine. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid administering other phototoxic drugs with aminolevulinic acid oral for 24 hr during perioperative period.aminolevulinic acid topicalSerious - Use Alternative (1)perphenazine increases toxicity of aminolevulinic acid topical by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration of photosensitizing drugs may enhance the phototoxic reaction to photodynamic therapy with aminolevulinic acid.amiodaroneSerious - Use Alternative (1)perphenazine and amiodarone both increase QTc interval. Avoid or Use Alternate Drug.Minor (1)amiodarone will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.amisulprideContraindicated (1)amisulpride, perphenazine. Either increases toxicity of the other by Other (see comment). Contraindicated. Comment: Increases risk of neuroleptic malignant syndrome.Serious - Use Alternative (1)perphenazine and amisulpride both increase QTc interval. Avoid or Use Alternate Drug. ECG monitoring is recommended if coadministered.amitriptylineMonitor Closely (1)perphenazine and amitriptyline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and amitriptyline both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)amitriptyline, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. amitriptyline, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.amobarbitalMonitor Closely (1)amobarbital and perphenazine both increase sedation. Use Caution/Monitor.amoxapineMonitor Closely (2)perphenazine and amoxapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely. perphenazine and amoxapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and amoxapine both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)amoxapine, perphenazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. amoxapine, perphenazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.anagrelideMonitor Closely (1)anagrelide and perphenazine both increase QTc interval. Use Caution/Monitor.anticholinergic/sedative combosMonitor Closely (3)anticholinergic/sedative combos decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. anticholinergic/sedative combos decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of anticholinergic/sedative combos by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.apomorphineMonitor Closely (1)perphenazine and apomorphine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)perphenazine decreases effects of apomorphine by pharmacodynamic antagonism. Avoid or Use Alternate Drug. apomorphine and perphenazine both increase QTc interval. Avoid or Use Alternate Drug.arformoterolMonitor Closely (2)arformoterol and perphenazine both increase QTc interval. Use Caution/Monitor. perphenazine increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.aripiprazoleMonitor Closely (2)aripiprazole and perphenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. aripiprazole and perphenazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)aripiprazole and perphenazine both increase QTc interval. Avoid or Use Alternate Drug.Minor (1)perphenazine will increase the level or effect of aripiprazole by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.armodafinilMonitor Closely (1)perphenazine increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.arsenic trioxideSerious - Use Alternative (1)perphenazine and arsenic trioxide both increase QTc interval. Avoid or Use Alternate Drug.artemetherMonitor Closely (1)artemether and perphenazine both increase QTc interval. Use Caution/Monitor.artemether/lumefantrineMonitor Closely (1)artemether/lumefantrine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)perphenazine and artemether/lumefantrine both increase QTc interval. Avoid or Use Alternate Drug.asenapineMonitor Closely (2)asenapine and perphenazine both increase QTc interval. Use Caution/Monitor. asenapine and perphenazine both increase sedation. Use Caution/Monitor.Minor (1)asenapine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.asenapine transdermalMonitor Closely (2)asenapine transdermal and perphenazine both increase QTc interval. Use Caution/Monitor. asenapine transdermal and perphenazine both increase sedation. Use Caution/Monitor.atomoxetineMonitor Closely (2)atomoxetine and perphenazine both increase QTc interval. Use Caution/Monitor. perphenazine will increase the level or effect of atomoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.atracuriumMonitor Closely (3)atracurium decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. atracurium decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of atracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.atropineMonitor Closely (3)atropine decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. atropine decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of atropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.Minor (1)perphenazine increases toxicity of atropine by unknown mechanism. Minor/Significance Unknown.atropine IV/IMMonitor Closely (3)perphenazine increases effects of atropine IV/IM by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. atropine IV/IM decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. atropine IV/IM decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor.Minor (1)perphenazine increases toxicity of atropine IV/IM by unknown mechanism. Minor/Significance Unknown.avapritinibMonitor Closely (1)avapritinib and perphenazine both increase sedation. Use Caution/Monitor.azelastineMonitor Closely (1)azelastine and perphenazine both increase sedation. Use Caution/Monitor.azithromycinMonitor Closely (1)perphenazine and azithromycin both increase QTc interval. Use Caution/Monitor.baclofenMonitor Closely (1)baclofen and perphenazine both increase sedation. Use Caution/Monitor.bedaquilineMonitor Closely (1)perphenazine and bedaquiline both increase QTc interval. Modify Therapy/Monitor Closely. ECG should be monitored closelybelladonna alkaloidsMonitor Closely (3)belladonna alkaloids decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. belladonna alkaloids decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of belladonna alkaloids by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.belladonna and opiumMonitor Closely (4)belladonna and opium decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. belladonna and opium decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor. perphenazine increases effects of belladonna and opium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. belladonna and opium and perphenazine both increase sedation. Use Caution/Monitor.benazeprilMinor (1)perphenazine increases effects of benazepril by unspecified interaction mechanism. Minor/Significance Unknown.benperidolMonitor Closely (2)benperidol and perphenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. benperidol and perphenazine both increase sedation. Use Caution/Monitor.benzhydrocodone/acetaminophenMonitor Closely (2)perphenazine will increase the level or effect of benzhydrocodone/acetaminophen by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone [benzhydrocodone is prodrug of hydrocodone]) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone. benzhydrocodone/acetaminophen and perphenazine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)benzhydrocodone/acetaminophen, perphenazine. Either increases toxicity 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. Increased risk of hypotension if ability to maintain blood pressure has been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (eg, phenothiazines or general anesthetics).benzphetamineMonitor Closely (2)perphenazine, benzphetamine. 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 benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.benztropineMonitor Closely (1)perphenazine increases effects of benztropine