CYP2D6 inhibitor PLUS a strong/moderate CYP3A4 inhibitor.haloperidol will increase the level or effect of brexpiprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Administer a quarter of brexpiprazole dose if coadministered with a moderate CYP3A4 inhibitor PLUS a strong/moderate CYP2D6 inhibitor.brexpiprazole and haloperidol both increase sedation. Use Caution/Monitor.brimonidinebrimonidine and haloperidol both increase sedation. Use Caution/Monitor.brivaracetambrivaracetam and haloperidol both increase sedation. Use Caution/Monitor.brompheniraminebrompheniramine and haloperidol both increase sedation. Use Caution/Monitor.buprenorphinebuprenorphine and haloperidol both increase sedation. Use Caution/Monitor.buprenorphine buccalbuprenorphine buccal and haloperidol both increase sedation. Use Caution/Monitor.buprenorphine subdermal implanthaloperidol will increase the level or effect of buprenorphine subdermal implant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor patients already on buprenorphine subdermal implant who require newly-initiated treatment with CYP3A4 inhibitors for signs and symptoms of overmedication. If the dose of the concomitant CYP3A4 inhibitor cannot be reduced or discontinued, implant removal may be necessary and the patient should then be treated with a buprenorphine dosage form that permits dose adjustments. If a CYP3A4 inhibitor is discontinued in a patient who has been stabilized on buprenorphine, monitor the patient for withdrawal.buprenorphine subdermal implant and haloperidol both increase sedation. Use Caution/Monitor.buprenorphine transdermalbuprenorphine transdermal and haloperidol both increase sedation. Use Caution/Monitor.buprenorphine, long-acting injectionhaloperidol will increase the level or effect of buprenorphine, long-acting injection by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Patients who transfer to buprenorphine long-acting injection from transmucosal buprenorphine coadministered with CYP3A4 inhibitors should be monitored to ensure buprenorphine plasma levels are adequate. Within 2 weeks, if signs and symptoms of buprenorphine toxicity or overdose occur and the concomitant CYP3A4 inhibitor cannot be reduced or discontinued, transition the patient back to a buprenorphine formulation that permits dose adjustments.haloperidol increases toxicity of buprenorphine, long-acting injection by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of buprenorphine and benzodiazepines or other CNS depressants increases risk of adverse reactions including overdose, respiratory depression, and death. Cessation of benzodiazepines or other CNS depressants is preferred in most cases. In some cases, monitoring at a higher level of care for tapering CNS depressants may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate.buprenorphine, long-acting injection and haloperidol both increase sedation. Use Caution/Monitor.bupropionbupropion will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.butabarbitalbutabarbital and haloperidol both increase sedation. Use Caution/Monitor.butalbitalbutalbital and haloperidol both increase sedation. Use Caution/Monitor.butorphanolbutorphanol and haloperidol both increase sedation. Use Caution/Monitor.cabozantinibhaloperidol will increase the level or effect of cabozantinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.caffeinehaloperidol increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.cannabidiolhaloperidol will increase the level or effect of cannabidiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Consider reducing the cannabidiol dose when coadministered with a moderate CYP3A4 inhibitor.capecitabinecapecitabine and haloperidol both increase QTc interval. Use Caution/Monitor.carbamazepinecarbamazepine decreases levels of haloperidol by increasing metabolism. Use Caution/Monitor.carbinoxaminecarbinoxamine and haloperidol both increase sedation. Use Caution/Monitor.carisoprodolcarisoprodol and haloperidol both increase sedation. Use Caution/Monitor.carvedilolhaloperidol will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.celecoxibcelecoxib will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.cenobamatecenobamate will decrease the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.chloral hydratechloral hydrate and haloperidol both increase sedation. Use Caution/Monitor.chlordiazepoxidechlordiazepoxide and haloperidol both increase sedation. Use Caution/Monitor.chloroquinechloroquine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.chloroquine increases toxicity of haloperidol by QTc interval. Use Caution/Monitor.chlorpheniraminechlorpheniramine and haloperidol both increase sedation. Use Caution/Monitor.chlorpromazinechlorpromazine and haloperidol both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.chlorpromazine and haloperidol both increase sedation. Use Caution/Monitor.chlorzoxazonechlorzoxazone and haloperidol both increase sedation. Use Caution/Monitor.cimetidinecimetidine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.cinnarizinecinnarizine and haloperidol both increase sedation. Use Caution/Monitor.ciprofloxacinciprofloxacin and haloperidol both increase QTc interval. Use Caution/Monitor. Ciprofloxacin elicits minimal effects on QT interval. Caution if used in combination with other drugs known to affect QT interval or in patients with other risk factors.cisatracuriumcisatracurium decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.cisatracurium decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of cisatracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.clemastineclemastine and haloperidol both increase sedation. Use Caution/Monitor.clobazamclobazam will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Lower doses of drugs metabolized by CYP2D6 may be required when used concomitantly. clomipraminehaloperidol and clomipramine both increase sedation. Use Caution/Monitor.clonazepamclonazepam and haloperidol both increase sedation. Use Caution/Monitor.clonidineclonidine, haloperidol. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects; potential delirium.clonidine increases toxicity of haloperidol by Other (see comment). Use Caution/Monitor. Comment: High doses of clonidine IV may increase arrhythmogenic potential (QT-prolongation, ventricular fibrillation) of high dose haloperidol IV in patients experiencing alcoholic delirium.clorazepateclorazepate and haloperidol both increase sedation. Use Caution/Monitor.clozapineclozapine and haloperidol both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.clozapine and haloperidol both increase sedation. Use Caution/Monitor.haloperidol and clozapine both increase QTc interval. Use Caution/Monitor.cobicistatcobicistat will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.codeinehaloperidol decreases effects of codeine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Prevents conversion of codeine to its active metabolite morphine.codeine and haloperidol both increase sedation. Use Caution/Monitor.conivaptanconivaptan will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.crizotinibcrizotinib increases levels of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dose reduction may be needed for coadministered drugs that are predominantly metabolized by CYP3A. ECG monitoring is recommended, along with drugs that may prolong the QT interval.crofelemercrofelemer increases levels of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Crofelemer has the potential to inhibit CYP3A4 at concentrations expected in the gut; unlikely to inhibit systemically because minimally absorbed.cyclizinecyclizine and haloperidol both increase sedation. Use Caution/Monitor.cyclizine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.cyclizine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of cyclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.cyclobenzaprinecyclobenzaprine and haloperidol both increase sedation. Use Caution/Monitor.cyclobenzaprine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.cyclobenzaprine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of cyclobenzaprine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.cyproheptadinecyproheptadine and haloperidol both increase sedation. Use Caution/Monitor.dabrafenibdabrafenib will decrease the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.dabrafenib and haloperidol both increase QTc interval. Use Caution/Monitor.dantrolenedantrolene and haloperidol both increase sedation. Use Caution/Monitor.daridorexanthaloperidol will increase the level or effect of daridorexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Daridorexant dose should not exceed 25 mg per night when coadministered with moderate CYP3A4 inhibitors.haloperidol and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment. darifenacindarifenacin will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.darifenacin decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.darifenacin decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of darifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.darunavirdarunavir will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.dasatinibdasatinib and haloperidol both increase QTc interval. Modify Therapy/Monitor Closely.deferasiroxdeferasirox will increase the level or effect of haloperidol by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.deflazacorthaloperidol will increase the level or effect of deflazacort by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Decrease deflazacort dose to one-third of the recommended dose if coadministered with moderate or strong CYP3A4 inhibitors.degarelixhaloperidol and degarelix both increase QTc interval. Use Caution/Monitor.desfluranedesflurane and haloperidol both increase sedation. Use Caution/Monitor.desipraminehaloperidol and desipramine both increase sedation. Use Caution/Monitor.desvenlafaxinedesvenlafaxine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Desvenlafaxine inhibits CYP2D6; with higher desvenlafaxine doses (ie, 400 mg) decrease the CYP2D6 substrate dose by up to 50%; no dosage adjustment needed with desvenlafaxine doses <100 mgdeutetrabenazinehaloperidol and deutetrabenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely. The risk for parkinsonism, neuroleptic malignant syndrome, and akathisia may be increased by concomitant use of deutetrabenazine and dopamine antagonists or antipsychotics.haloperidol and deutetrabenazine both increase sedation. Use Caution/Monitor.haloperidol and deutetrabenazine both increase QTc interval. Use Caution/Monitor. At the maximum recommended dose, deutetrabenazine does not prolong QT interval to a clinically relevant extent. Certain circumstances may increase risk of torsade de pointes and/or sudden death in association with drugs that prolong the QTc interval (eg, bradycardia, hypokalemia or hypomagnesemia, coadministration with other drugs that prolong QTc interval, presence of congenital QT prolongation).dexchlorpheniraminedexchlorpheniramine and haloperidol both increase sedation. Use Caution/Monitor.dexfenfluraminehaloperidol increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dexmedetomidinedexmedetomidine and haloperidol both increase sedation. Use Caution/Monitor.dexmethylphenidatehaloperidol increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dextroamphetaminehaloperidol increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dextromethorphandextromethorphan, 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).dextromoramidedextromoramide and haloperidol both increase sedation. Use Caution/Monitor.diamorphinediamorphine and haloperidol both increase sedation. Use Caution/Monitor.diazepamdiazepam and haloperidol both increase sedation. Use Caution/Monitor.diazepam intranasalhaloperidol will increase the level or effect of diazepam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.dicyclominedicyclomine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.dicyclomine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of dicyclomine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.diethylpropionhaloperidol increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.difelikefalindifelikefalin and haloperidol both increase sedation. Use Caution/Monitor.difenoxin hcldifenoxin hcl and haloperidol both increase sedation. Use Caution/Monitor.dihydroergotaminedihydroergotamine, 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).dimenhydrinatedimenhydrinate and haloperidol both increase sedation. Use Caution/Monitor.diphenhydraminediphenhydramine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and haloperidol both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.diphenoxylate hcldiphenoxylate hcl and haloperidol both increase sedation. Use Caution/Monitor.dipipanonedipipanone and haloperidol both increase sedation. Use Caution/Monitor.dobutaminehaloperidol increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dolasetrondolasetron and haloperidol both increase QTc interval. Modify Therapy/Monitor Closely.donepezildonepezil and haloperidol both increase QTc interval. Use Caution/Monitor.donepezil transdermaldonepezil transdermal, haloperidol. Either decreases effects of the other by pharmacodynamic antagonism. Use Caution/Monitor.dopaminehaloperidol increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dopexaminehaloperidol increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.dosulepinhaloperidol and dosulepin both increase sedation. Use Caution/Monitor.doxepinhaloperidol and doxepin both increase sedation. Use Caution/Monitor.doxylaminedoxylamine and haloperidol both increase sedation. Use Caution/Monitor.dronedaronedronedarone will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.droperidoldroperidol and haloperidol both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.droperidol and haloperidol both increase sedation. Use Caution/Monitor.duvelisibduvelisib will increase the level or effect of haloperidol by affecting hepatic/intestinal enzyme CYP3A4