with a significant prolongation of the QTc interval in rare instanceslofepramineMonitor Closely (1)olanzapine and lofepramine both increase sedation. Use Caution/Monitor.lofexidineMonitor Closely (2)olanzapine and lofexidine both increase QTc interval. Use Caution/Monitor. olanzapine and lofexidine both increase sedation. Use Caution/Monitor.lomitapideMonitor Closely (1)olanzapine increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.lonafarnibSerious - Use Alternative (1)olanzapine will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.lonapegsomatropinMonitor Closely (1)lonapegsomatropin will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Limited published data indicate that growth hormone treatment increases cytochrome P450 (CYP450)-mediated antipyrine clearance. Caution with sensitive CYP substratesloperamideMonitor Closely (1)olanzapine and loperamide both increase QTc interval. Use Caution/Monitor.lopinavirSerious - Use Alternative (1)olanzapine and lopinavir both increase QTc interval. Avoid or Use Alternate Drug.loprazolamMonitor Closely (1)loprazolam and olanzapine both increase sedation. Use Caution/Monitor.lorazepamMonitor Closely (1)lorazepam and olanzapine both increase sedation. Use Caution/Monitor.lorcaserinMonitor Closely (1)lorcaserin, olanzapine. 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).lormetazepamMonitor Closely (1)lormetazepam and olanzapine both increase sedation. Use Caution/Monitor.loxapineMonitor Closely (2)loxapine and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. loxapine and olanzapine both increase sedation. Use Caution/Monitor.loxapine inhaledMonitor Closely (2)loxapine inhaled and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor. loxapine inhaled and olanzapine both increase sedation. Use Caution/Monitor.lurasidoneMonitor Closely (1)lurasidone, olanzapine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.macimorelinSerious - Use Alternative (1)macimorelin and olanzapine 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 (1)olanzapine and maprotiline both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)olanzapine and maprotiline both increase QTc interval. Avoid or Use Alternate Drug.maravirocMonitor Closely (1)maraviroc, olanzapine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.marijuanaMonitor Closely (1)olanzapine and marijuana both increase sedation. Use Caution/Monitor.mavacamtenMonitor Closely (1)olanzapine will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Inititiation of weak CYP2C19 inhibitors may require decreased mavacamten dose. meclizineMonitor Closely (3)meclizine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. meclizine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor. olanzapine increases effects of meclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.mefloquineSerious - Use Alternative (1)mefloquine increases toxicity of olanzapine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.melatoninMonitor Closely (1)olanzapine and melatonin both increase sedation. Use Caution/Monitor.meperidineMonitor Closely (2)meperidine, olanzapine. 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 olanzapine both increase sedation. Use Caution/Monitor.meprobamateMonitor Closely (1)olanzapine and meprobamate both increase sedation. Use Caution/Monitor.metaproterenolMonitor Closely (1)olanzapine increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.metaxaloneMonitor Closely (1)metaxalone and olanzapine both increase sedation. Use Caution/Monitor.metforminMonitor Closely (1)olanzapine, 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 (2)methadone, olanzapine. 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 olanzapine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)olanzapine and methadone both increase QTc interval. Avoid or Use Alternate Drug.methamphetamineMonitor Closely (1)olanzapine increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methocarbamolMonitor Closely (1)methocarbamol and olanzapine both increase sedation. Use Caution/Monitor.methscopolamineMonitor Closely (3)methscopolamine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. methscopolamine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor. olanzapine increases effects of methscopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.methyldopaSerious - Use Alternative (1)olanzapine decreases effects of methyldopa by pharmacodynamic antagonism. Contraindicated.methylenedioxymethamphetamineMonitor Closely (1)olanzapine increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methylergonovineMonitor Closely (1)methylergonovine, olanzapine. 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)olanzapine 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.metoclopramideMonitor Closely (1)olanzapine and metoclopramide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.metoclopramide intranasalSerious - Use Alternative (2)olanzapine, 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. olanzapine 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.mexiletineMonitor Closely (1)mexiletine will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.midazolamMonitor Closely (1)midazolam and olanzapine both increase sedation. Use Caution/Monitor.midazolam intranasalMonitor Closely (2)olanzapine will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation. midazolam intranasal, olanzapine. 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)olanzapine increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.midostaurinSerious - Use Alternative (1)olanzapine and midostaurin both increase QTc interval. Avoid or Use Alternate Drug.mifepristoneMonitor Closely (1)mifepristone, olanzapine. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.miglitolMonitor Closely (1)olanzapine, 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, olanzapine. 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 (3)mirtazapine and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances olanzapine and mirtazapine both increase sedation. Use Caution/Monitor. olanzapine and mirtazapine both increase QTc interval. Use Caution/Monitor.mobocertinibSerious - Use Alternative (1)mobocertinib and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.modafinilMonitor Closely (2)modafinil will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. olanzapine increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.morphineMonitor Closely (1)morphine and olanzapine both increase sedation. Use Caution/Monitor.motherwortMonitor Closely (1)olanzapine and motherwort both increase sedation. Use Caution/Monitor.moxifloxacinSerious - Use Alternative (1)olanzapine and moxifloxacin both increase QTc interval. Avoid or Use Alternate Drug.moxonidineMonitor Closely (1)olanzapine and moxonidine both increase sedation. Use Caution/Monitor.nabiloneMonitor Closely (1)olanzapine and nabilone both increase sedation. Use Caution/Monitor.nalbuphineMonitor Closely (1)nalbuphine and olanzapine both increase sedation. Use Caution/Monitor.naratriptanMonitor Closely (1)naratriptan, olanzapine. 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)olanzapine, 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.norepinephrineMonitor Closely (1)olanzapine increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.nortriptylineMonitor Closely (2)olanzapine and nortriptyline both increase QTc interval. Use Caution/Monitor. olanzapine and nortriptyline both increase sedation. Use Caution/Monitor.ofloxacinMonitor Closely (1)olanzapine and ofloxacin both increase QTc interval. Use Caution/Monitor.oliceridineMonitor Closely (1)oliceridine, olanzapine. 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.olopatadine intranasalSerious - Use Alternative (1)olanzapine and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment. omeprazoleMinor (1)omeprazole will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.onabotulinumtoxinAMonitor Closely (3)onabotulinumtoxinA decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. onabotulinumtoxinA decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor. olanzapine increases effects of onabotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.ondansetronSerious - Use Alternative (1)olanzapine and ondansetron both increase QTc interval. Avoid or Use Alternate Drug. Avoid with congenital long QT syndrome; ECG monitoring recommended with concomitant medications that prolong QT interval, electrolyte abnormalities, CHF, or bradyarrhythmias.opium tinctureMonitor Closely (1)opium tincture and olanzapine both increase sedation. Use Caution/Monitor.orphenadrineMonitor Closely (1)orphenadrine and olanzapine both increase sedation. Use Caution/Monitor.osilodrostatMonitor Closely (1)osilodrostat and olanzapine both increase QTc interval. Use Caution/Monitor.osimertinibMonitor Closely (1)osimertinib and olanzapine both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.oxaliplatinMonitor Closely (1)oxaliplatin will increase the level or effect of olanzapine by Other (see comment). Use Caution/Monitor. Monitor for ECG changes if therapy is initiated in patients with drugs known to prolong QT interval.Serious - Use Alternative (2)olanzapine and oxaliplatin both increase QTc interval. Avoid or Use Alternate Drug. oxaliplatin and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instancesoxazepamMonitor Closely (1)oxazepam and olanzapine both increase sedation. Use Caution/Monitor.oxybutyninMonitor Closely (3)oxybutynin decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. oxybutynin decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor. olanzapine increases effects of oxybutynin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.oxybutynin topicalMonitor Closely (3)oxybutynin topical decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. oxybutynin topical decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor. olanzapine increases