inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. belladonna and opium decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of belladonna and opium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. belladonna and opium and quetiapine both increase sedation. Use Caution/Monitor.benazeprilMonitor Closely (2)benazepril increases toxicity of quetiapine by pharmacodynamic synergism. Use Caution/Monitor. Increases risk of hypotension. quetiapine increases toxicity of benazepril by pharmacodynamic synergism. Use Caution/Monitor. Increases risk of hypotension.benperidolMonitor Closely (2)benperidol and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. benperidol and quetiapine both increase sedation. Use Caution/Monitor.benzhydrocodone/acetaminophenSerious - Use Alternative (2)benzhydrocodone/acetaminophen, quetiapine. 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. benzhydrocodone/acetaminophen and quetiapine both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequatebenzphetamineMonitor Closely (1)quetiapine increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.benztropineMonitor Closely (1)quetiapine increases effects of benztropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic adverse effects may be seen with concurrent use. .bosentanMonitor Closely (1)bosentan will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.brexanoloneMonitor Closely (1)brexanolone, quetiapine. Either increases toxicity of the other by sedation. Use Caution/Monitor.brexpiprazoleMonitor Closely (1)brexpiprazole and quetiapine both increase sedation. Use Caution/Monitor.brimonidineMonitor Closely (1)brimonidine and quetiapine both increase sedation. Use Caution/Monitor.Minor (1)brimonidine increases effects of quetiapine by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.brivaracetamMonitor Closely (1)brivaracetam and quetiapine both increase sedation. Use Caution/Monitor.bromocriptineSerious - Use Alternative (1)quetiapine decreases effects of bromocriptine by pharmacodynamic antagonism. Avoid or Use Alternate Drug.brompheniramineMonitor Closely (1)brompheniramine and quetiapine both increase sedation. Use Caution/Monitor.budesonideMonitor Closely (1)budesonide will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.buprenorphineMonitor Closely (1)buprenorphine and quetiapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)buprenorphine and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.buprenorphine buccalMonitor Closely (1)buprenorphine buccal and quetiapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)buprenorphine buccal and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.buprenorphine subdermal implantSerious - Use Alternative (2)buprenorphine subdermal implant and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. buprenorphine subdermal implant and quetiapine both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequatebuprenorphine transdermalSerious - Use Alternative (2)buprenorphine transdermal and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. buprenorphine transdermal and quetiapine both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequatebuprenorphine, long-acting injectionMonitor Closely (1)quetiapine 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.Serious - Use Alternative (2)buprenorphine, long-acting injection and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. buprenorphine, long-acting injection and quetiapine both increase sedation. Avoid or Use Alternate Drug. Limit use to patients for whom alternative treatment options are inadequatebutabarbitalMonitor Closely (2)butabarbital will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. butabarbital and quetiapine both increase sedation. Use Caution/Monitor.butalbitalMonitor Closely (2)butalbital will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. butalbital and quetiapine both increase sedation. Use Caution/Monitor.butorphanolMonitor Closely (1)butorphanol and quetiapine both increase sedation. Use Caution/Monitor.cabergolineSerious - Use Alternative (1)quetiapine decreases effects of cabergoline by pharmacodynamic antagonism. Contraindicated.caffeineMonitor Closely (1)quetiapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.calcium/magnesium/potassium/sodium oxybatesSerious - Use Alternative (1)quetiapine, calcium/magnesium/potassium/sodium oxybates. 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.captoprilMonitor Closely (1)quetiapine, captopril. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.carbamazepineMonitor Closely (1)quetiapine will increase the level or effect of carbamazepine by decreasing metabolism. Modify Therapy/Monitor Closely. Monitor plasma levels when used concomitantlySerious - Use Alternative (1)carbamazepine will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.carbinoxamineMonitor Closely (1)carbinoxamine and quetiapine both increase sedation. Use Caution/Monitor.carisoprodolMonitor Closely (1)carisoprodol and quetiapine both increase sedation. Use Caution/Monitor.cenobamateMonitor Closely (2)cenobamate, quetiapine. Either increases effects of the other by sedation. Use Caution/Monitor. cenobamate will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.ceritinibSerious - Use Alternative (2)ceritinib and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. ceritinib will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.chasteberryMinor (1)chasteberry decreases effects of quetiapine by pharmacodynamic antagonism. Minor/Significance Unknown. (Theoretical interaction).chloral hydrateMonitor Closely (1)chloral hydrate and quetiapine both increase sedation. Use Caution/Monitor.chloramphenicolSerious - Use Alternative (1)chloramphenicol will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.chlordiazepoxideMonitor Closely (1)chlordiazepoxide and quetiapine both increase sedation. Use Caution/Monitor.chloroquineMonitor Closely (1)chloroquine increases toxicity of quetiapine by QTc interval. Use Caution/Monitor.chlorpheniramineMonitor Closely (1)chlorpheniramine and quetiapine both increase sedation. Use Caution/Monitor.chlorpromazineMonitor Closely (3)chlorpromazine and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. chlorpromazine and quetiapine both increase sedation. Use Caution/Monitor. quetiapine, chlorpromazine. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.chlorpropamideMonitor Closely (1)quetiapine, chlorpropamide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.chlorzoxazoneMonitor Closely (1)chlorzoxazone and quetiapine both increase sedation. Use Caution/Monitor.cimetidineSerious - Use Alternative (1)cimetidine will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.cinnarizineMonitor Closely (1)cinnarizine and quetiapine both increase sedation. Use Caution/Monitor.ciprofloxacinMonitor Closely (1)quetiapine, ciprofloxacin. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.cisatracuriumMonitor Closely (3)cisatracurium decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. cisatracurium decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of cisatracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.citalopramMonitor Closely (1)quetiapine, citalopram. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT interval and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT. ECG monitoring is recommended.clarithromycinMonitor Closely (1)quetiapine, clarithromycin. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.Serious - Use Alternative (1)clarithromycin will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.clemastineMonitor Closely (1)clemastine and quetiapine both increase sedation. Use Caution/Monitor.clobazamMonitor Closely (1)quetiapine, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).clomipramineMonitor Closely (2)quetiapine and clomipramine both increase sedation. Use Caution/Monitor. quetiapine, clomipramine. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.clonazepamMonitor Closely (1)clonazepam and quetiapine both increase sedation. Use Caution/Monitor.clonidineMonitor Closely (1)clonidine, quetiapine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects; potential delirium.clorazepateMonitor Closely (1)clorazepate and quetiapine both increase sedation. Use Caution/Monitor.clozapineMonitor Closely (2)clozapine and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. clozapine and quetiapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)clozapine and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.cobicistatSerious - Use Alternative (1)cobicistat increases levels of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with atazanavir and cobicistat in patients taking quetiapine. If coadministration is necessary, reduce quetiapine dose to one-sixth of the current dose and monitor for quetiapine-associated adverse reactions. Refer to quetiapine prescribing information for initial dosing and titration of quetiapine.codeineMonitor Closely (1)codeine and quetiapine both increase sedation. Use Caution/Monitor.conivaptanMonitor Closely (1)conivaptan will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.cortisoneMonitor Closely (1)cortisone will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.crizotinibMonitor Closely (1)crizotinib increases levels of quetiapine 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.Serious - Use Alternative (1)crizotinib and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.crofelemerMonitor Closely (1)crofelemer increases levels of quetiapine 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.cyclizineMonitor Closely (4)cyclizine decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. cyclizine decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of cyclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. cyclizine and quetiapine both increase sedation. Use Caution/Monitor.cyclobenzaprineMonitor Closely (5)cyclobenzaprine decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. cyclobenzaprine decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of cyclobenzaprine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia. cyclobenzaprine and quetiapine both increase sedation. Use Caution/Monitor. quetiapine, cyclobenzaprine. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.cyclophosphamideMinor (1)cyclophosphamide will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.cyclosporineMonitor Closely (1)cyclosporine will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.cyproheptadineMonitor Closely (1)cyproheptadine and quetiapine both increase sedation. Use Caution/Monitor.dabrafenibSerious - Use Alternative (1)dabrafenib will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.dantroleneMonitor Closely (1)dantrolene and quetiapine both increase sedation. Use Caution/Monitor.daridorexantMonitor Closely (1)quetiapine 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. darifenacinMonitor Closely (4)darifenacin will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. darifenacin decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. darifenacin