increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.quinupristin/dalfopristinquinupristin/dalfopristin increases levels of haloperidol by decreasing metabolism. Contraindicated. Risk of prolonged QTc interval.ribociclibribociclib and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.romidepsinhaloperidol and romidepsin both increase QTc interval. Avoid or Use Alternate Drug.ropeginterferon alfa 2bropeginterferon alfa 2b, haloperidol. Either increases toxicity of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Myelosuppressive agents can produce additive myelosuppression. Avoid use and monitor patients receiving the combination for effects of excessive myelosuppression.ropinirolehaloperidol decreases effects of ropinirole by pharmacodynamic antagonism. Contraindicated.safinamidehaloperidol decreases effects of safinamide by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Dopamine antagonists may decrease safinamide effects and exacerbate Parkinson disease symptoms.saquinavirsaquinavir increases levels of haloperidol by QTc interval. Avoid or Use Alternate Drug. Potential for increased toxicity. Increased risk of QT prolongation and cardiac arrhythmias.saquinavir increases levels of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Potential for increased toxicity. Increased risk of QT prolongation and cardiac arrhythmias.selinexorselinexor, haloperidol. 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.selumetinibhaloperidol will increase the level or effect of selumetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors cannot be avoided, reduce selumetinib dosage (refer to selumetinib monograph for further information). After discontinuation of the strong or moderate CYP3A4 inhibitor for 3 elimination half-lives, resume selumetinib dose that was taken before initiating the inhibitor.sevofluranesevoflurane and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.siponimodhaloperidol will increase the level or effect of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with a moderate or strong CYP3A4 inhibitor PLUS a moderate or strong CYP2C9 inhibitor is not recommended.siponimod and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.sodium oxybatehaloperidol, 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.sufentanil SLsufentanil SL, haloperidol. 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.tazemetostathaloperidol will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of tazemetostat with moderate CYP3A4 inhibitors. If coadministration is unavoidable, reduce tazemetostat current dose (see drug monograph Dosage Modifications). tetrabenazinetetrabenazine and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.thioridazinehaloperidol will increase the level or effect of thioridazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.thioridazine and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.toremifenehaloperidol and toremifene both increase QTc interval. Avoid or Use Alternate Drug. Concurrent use of toremifene with agents causing QT prolongation should be avoided. If concomitant use is required it's recommended that toremifene be interrupted. If interruption not possible, patients requiring therapy with a drug that prolongs QT should be closely monitored. ECGs should be obtained for high risk patients.trazodonetrazodone and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.trifluoperazinetrifluoperazine and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.trimipraminetrimipramine and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.tucatinibtucatinib will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.umeclidinium bromide/vilanterol inhaledhaloperidol 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.vandetanibhaloperidol, vandetanib. Either increases toxicity of the other by QTc interval. Avoid or Use Alternate Drug. Avoid coadministration with drugs known to prolong QT interval; if a drug known to prolong QT interval must be used, more frequent ECG monitoring is recommended.vemurafenibvemurafenib and haloperidol both increase QTc interval. Avoid or Use Alternate Drug. Concomitant use of vemurafenib with drugs that prolong QT interval is not recommended.venetoclaxhaloperidol will increase the level or effect of venetoclax by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If a moderate CYP3A inhibitor must be used, reduce the venetoclax dose by at least 50%. Monitor more closely for signs of venetoclax toxicities.vilanterol/fluticasone furoate inhaledhaloperidol 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.voxelotorvoxelotor will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.ziprasidonehaloperidol and ziprasidone both increase QTc interval. Avoid or Use Alternate Drug.Monitor Closely (433)abirateroneabiraterone increases levels of haloperidol 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.abobotulinumtoxinAabobotulinumtoxinA increases effects of haloperidol by pharmacodynamic synergism. Use Caution/Monitor. Use of anticholinergic drugs after administration of botulinum toxin-containing products may potentiate systemic anticholinergic effects.acalabrutinibhaloperidol will increase the level or effect of acalabrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Decrease acalabrutinib dose to 100 mg once daily if coadministered with a moderate CYP3A inhibitor.acalabrutinib, haloperidol. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may increase risk of myelosuppressive effects.aclidiniumaclidinium decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of aclidinium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.acrivastineacrivastine and haloperidol both increase sedation. Use Caution/Monitor.albuterolhaloperidol increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.albuterol and haloperidol both increase QTc interval. Use Caution/Monitor.alfentanilalfentanil and haloperidol both increase sedation. Use Caution/Monitor.alfuzosinhaloperidol and alfuzosin both increase QTc interval. Use Caution/Monitor.alfuzosin and haloperidol both increase QTc interval. Use Caution/Monitor.almotriptanalmotriptan, haloperidol. 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).alprazolamalprazolam and haloperidol both increase sedation. Use Caution/Monitor.amifampridinehaloperidol 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.amitriptylinehaloperidol and amitriptyline both increase sedation. Use Caution/Monitor.amobarbitalamobarbital and haloperidol both increase sedation. Use Caution/Monitor.amobarbital will decrease the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.amoxapinehaloperidol and amoxapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely.haloperidol and amoxapine both increase sedation. Use Caution/Monitor.anticholinergic/sedative combosanticholinergic/sedative combos decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.anticholinergic/sedative combos decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of anticholinergic/sedative combos by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.apomorphinehaloperidol and apomorphine both increase sedation. Use Caution/Monitor.haloperidol and apomorphine both increase QTc interval. Use Caution/Monitor.arformoterolhaloperidol increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.haloperidol and arformoterol both increase QTc interval. Use Caution/Monitor.aripiprazolearipiprazole and haloperidol both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.aripiprazole and haloperidol both increase sedation. Use Caution/Monitor.aripiprazole and haloperidol both increase QTc interval. Use Caution/Monitor.armodafinilhaloperidol increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.artemetherhaloperidol and artemether both increase QTc interval. Use Caution/Monitor.asenapineasenapine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.haloperidol and asenapine both increase QTc interval. Use Caution/Monitor.asenapine and haloperidol both increase sedation. Use Caution/Monitor.asenapine transdermalasenapine transdermal and haloperidol both increase QTc interval. Use Caution/Monitor.asenapine transdermal and haloperidol both increase sedation. Use Caution/Monitor.atazanaviratazanavir will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.atogepanthaloperidol will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.atomoxetinehaloperidol will increase the level or effect of atomoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.atomoxetine and haloperidol both increase QTc interval. Use Caution/Monitor.atracuriumatracurium decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.atracurium decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of atracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.atropineatropine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.atropine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of atropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.atropine IV/IMhaloperidol increases effects of atropine IV/IM by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.atropine IV/IM decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.atropine IV/IM decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.avanafilhaloperidol will increase the level or effect of avanafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce avanafil clearance increasing systemic exposure to avanafil; increased levels may result in increased associated adverse events; the maximum recommended dose of STENDRA is 50 mg, not to exceed once every 24 hours for patients taking concomitant moderate CYP3A4 inhibitorsavapritinibavapritinib and haloperidol both increase sedation. Use Caution/Monitor.azelastineazelastine and haloperidol both increase sedation. Use Caution/Monitor.azithromycinazithromycin and haloperidol both increase QTc interval. Use Caution/Monitor.baclofenbaclofen and haloperidol both increase sedation. Use Caution/Monitor.bedaquilinehaloperidol and bedaquiline both increase QTc interval. Modify Therapy/Monitor Closely. ECG should be monitored closelybelladonna alkaloidsbelladonna alkaloids decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.belladonna alkaloids decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of belladonna alkaloids by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.belladonna and opiumbelladonna and opium and haloperidol both increase sedation. Use Caution/Monitor.belladonna and opium decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.belladonna and opium decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of belladonna and opium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.belzutifanbelzutifan will decrease the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If unable to avoid coadministration of belzutifan with sensitive CYP3A4 substrates, consider increasing the sensitive CYP3A4 substrate dose in accordance with its prescribing information. benperidolbenperidol and haloperidol both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.benperidol and haloperidol both increase sedation. Use Caution/Monitor.benzhydrocodone/acetaminophenhaloperidol 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 haloperidol both increase sedation. Use Caution/Monitor.benzphetaminehaloperidol increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.benztropinehaloperidol increases effects of benztropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic adverse effects may be seen with concurrent use. .bosentanbosentan will decrease the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.bosutinibbosutinib and haloperidol both increase QTc interval. Use Caution/Monitor.brexanolonebrexanolone, haloperidol. Either increases toxicity of the other by sedation. Use Caution/Monitor.brexpiprazolehaloperidol will increase the level or effect of brexpiprazole by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Administer a quarter of brexpiprazole dose if coadministered with a moderate