(2)loxapine inhaled and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. loxapine inhaled and quetiapine both increase sedation. Use Caution/Monitor.lumefantrineMonitor Closely (2)lumefantrine will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. quetiapine, lumefantrine. 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.lurasidoneMonitor Closely (1)lurasidone, quetiapine. Either increases toxicity of the other by sedation. Use Caution/Monitor. Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.macimorelinSerious - Use Alternative (1)macimorelin and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. Macimorelin causes an increase of ~11 msec in the corrected QT interval. Avoid coadministration with drugs that prolong QT interval, which could increase risk for developing torsade de pointes-type ventricular tachycardia. Allow sufficient washout time of drugs that are known to prolong the QT interval before administering macimorelin.maprotilineMonitor Closely (2)quetiapine and maprotiline both increase sedation. Use Caution/Monitor. quetiapine, maprotiline. 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.maravirocMonitor Closely (1)maraviroc, quetiapine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.marijuanaMonitor Closely (2)marijuana will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. quetiapine and marijuana both increase sedation. Use Caution/Monitor.meclizineMonitor Closely (3)meclizine decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. meclizine decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of meclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.mefloquineMonitor Closely (1)quetiapine, mefloquine. 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)mefloquine increases toxicity of quetiapine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.melatoninMonitor Closely (1)quetiapine and melatonin both increase sedation. Use Caution/Monitor.meperidineMonitor Closely (2)meperidine, quetiapine. 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). meperidine and quetiapine both increase sedation. Use Caution/Monitor.meprobamateMonitor Closely (1)quetiapine and meprobamate both increase sedation. Use Caution/Monitor.metaproterenolMonitor Closely (1)quetiapine increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.metaxaloneMonitor Closely (1)metaxalone and quetiapine both increase sedation. Use Caution/Monitor.metforminMonitor Closely (1)quetiapine, metformin. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.methadoneMonitor Closely (3)methadone, quetiapine. 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). methadone and quetiapine both increase sedation. Use Caution/Monitor. quetiapine, methadone. 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.methamphetamineMonitor Closely (1)quetiapine increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methocarbamolMonitor Closely (1)methocarbamol and quetiapine both increase sedation. Use Caution/Monitor.methscopolamineMonitor Closely (3)methscopolamine decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. methscopolamine decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor. quetiapine increases effects of methscopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.methyldopaSerious - Use Alternative (1)quetiapine decreases effects of methyldopa by pharmacodynamic antagonism. Contraindicated.methylenedioxymethamphetamineMonitor Closely (1)quetiapine increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methylergonovineMonitor Closely (1)methylergonovine, quetiapine. 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).methylphenidateMonitor Closely (1)quetiapine increases toxicity of methylphenidate by pharmacodynamic antagonism. Use Caution/Monitor. Closely monitor for signs of altered clinical response to either methylphenidate or an antipsychotic when using these drugs in combination.methylprednisoloneMonitor Closely (1)methylprednisolone will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.metoclopramideMonitor Closely (1)quetiapine and metoclopramide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.metoclopramide intranasalSerious - Use Alternative (2)quetiapine, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient. quetiapine increases toxicity of metoclopramide intranasal by pharmacodynamic synergism. Avoid or Use Alternate Drug. Potential for additive effects, including increased frequency and severity of tardive dyskinesia, other extrapyramidal symptoms, and neuroleptic malignant syndrome.metronidazoleMonitor Closely (1)metronidazole will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.miconazole vaginalMonitor Closely (1)miconazole vaginal will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.midazolamMonitor Closely (1)midazolam and quetiapine both increase sedation. Use Caution/Monitor.midazolam intranasalMonitor Closely (1)midazolam intranasal, quetiapine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.midodrineMonitor Closely (1)quetiapine increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.mifepristoneMonitor Closely (1)mifepristone, quetiapine. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.Serious - Use Alternative (1)mifepristone will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.miglitolMonitor Closely (1)quetiapine, miglitol. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.milnacipranMonitor Closely (1)milnacipran, quetiapine. 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).mirtazapineMonitor Closely (1)quetiapine and mirtazapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)mirtazapine and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.mitotaneMonitor Closely (1)mitotane decreases levels of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.mobocertinibSerious - Use Alternative (1)mobocertinib and quetiapine both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.modafinilMonitor Closely (1)quetiapine increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.morphineMonitor Closely (1)morphine and quetiapine both increase sedation. Use Caution/Monitor.motherwortMonitor Closely (1)quetiapine and motherwort both increase sedation. Use Caution/Monitor.moxifloxacinMonitor Closely (1)quetiapine, moxifloxacin. 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.moxonidineMonitor Closely (1)quetiapine and moxonidine both increase sedation. Use Caution/Monitor.nabiloneMonitor Closely (1)quetiapine and nabilone both increase sedation. Use Caution/Monitor.nafcillinMonitor Closely (1)nafcillin will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nalbuphineMonitor Closely (1)nalbuphine and quetiapine both increase sedation. Use Caution/Monitor.naratriptanMonitor Closely (1)naratriptan, quetiapine. 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).nateglinideMonitor Closely (1)quetiapine, nateglinide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.nefazodoneSerious - Use Alternative (1)nefazodone will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.nelfinavirMonitor Closely (1)nelfinavir will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nevirapineMonitor Closely (1)nevirapine will decrease the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nifedipineMonitor Closely (1)nifedipine will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nilotinibMonitor Closely (2)nilotinib will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. quetiapine, nilotinib. 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.nirmatrelvirMonitor Closely (1)nirmatrelvir will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce quetiapine dose to one-sixth when coadministered with strong CYP3A4 inhibitors. nirmatrelvir/ritonavirMonitor Closely (1)nirmatrelvir/ritonavir will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce quetiapine dose to one-sixth when coadministered with strong CYP3A4 inhibitors. norepinephrineMonitor Closely (1)quetiapine increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.nortriptylineMonitor Closely (2)quetiapine and nortriptyline both increase sedation. Use Caution/Monitor. quetiapine, nortriptyline. 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.octreotideMonitor Closely (1)quetiapine, octreotide. 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.ofloxacinMonitor Closely (1)quetiapine, ofloxacin. 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.olanzapineMonitor Closely (2)olanzapine and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. olanzapine and quetiapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)olanzapine and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.oliceridineMonitor Closely (1)oliceridine, quetiapine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. 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.olodaterol inhaledMonitor Closely (1)quetiapine and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. Drugs that prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk