and levomilnacipran both increase serotonin levels. Avoid or Use Alternate Drug.linezolidContraindicated (1)linezolid and fluoxetine both increase serotonin levels. Contraindicated. Linezolid may increase serotonin as a result of MAO-A inhibition. If linezolid must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last linezolid dose or after 5 weeks of monitoring, whichever comes first.lisdexamfetamineMonitor Closely (1)fluoxetine, lisdexamfetamine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue along with concomitant serotonergic drug(s).lithiumMonitor Closely (2)fluoxetine and lithium both increase serotonin levels. Modify Therapy/Monitor Closely. lithium and fluoxetine both increase QTc interval. Use Caution/Monitor.Minor (1)fluoxetine, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.lofepramineSerious - Use Alternative (2)fluoxetine and lofepramine both increase serotonin levels. Avoid or Use Alternate Drug. fluoxetine will increase the level or effect of lofepramine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.lofexidineMonitor Closely (2)fluoxetine and lofexidine both increase QTc interval. Use Caution/Monitor. ECG monitoring is recommended. fluoxetine will increase the level or effect of lofexidine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Concomitant use of lofexidine with strong CYP2D6 inhibitors may increase lofexidine plasma levels. Monitor for symptoms of orthostasis and bradycardia if coadministered with a CYP2D6 inhibitor. Consider lofexidine dose reduction.lomitapideMonitor Closely (1)fluoxetine 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)fluoxetine 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.loratadineMonitor Closely (1)fluoxetine will increase the level or effect of loratadine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.lorcaserinMonitor Closely (1)lorcaserin will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)fluoxetine and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.lornoxicamMonitor Closely (1)fluoxetine, lornoxicam. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.losartanMonitor Closely (1)fluoxetine will increase the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.Minor (1)fluoxetine decreases effects of losartan by decreasing metabolism. Minor/Significance Unknown. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.lsdMonitor Closely (1)fluoxetine and lsd both increase serotonin levels. Modify Therapy/Monitor Closely.lumacaftor/ivacaftorMonitor Closely (1)lumacaftor/ivacaftor, fluoxetine. affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2C9 substrates. .lumefantrineContraindicated (1)lumefantrine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated.Monitor Closely (1)fluoxetine and lumefantrine both increase QTc interval. Modify Therapy/Monitor Closely.lurasidoneMonitor Closely (1)lurasidone, fluoxetine. 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 fluoxetine 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)maprotiline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)fluoxetine and maprotiline both increase serotonin levels. Avoid or Use Alternate Drug.maravirocMinor (1)maraviroc will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.marijuanaMinor (1)marijuana will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.mavacamtenContraindicated (1)fluoxetine will increase the level or effect of mavacamten by affecting hepatic enzyme CYP2C19 metabolism. Contraindicated. Strong or moderate CYP2C19 inhibitors may increase mavacamten systemic exposure, resulting in heart failure due to systolic dysfunction. meclofenamateMonitor Closely (1)fluoxetine, meclofenamate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.mefenamic acidMonitor Closely (1)fluoxetine, mefenamic acid. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.mefloquineSerious - Use Alternative (1)mefloquine increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.meloxicamMonitor Closely (2)fluoxetine will increase the level or effect of meloxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. fluoxetine, meloxicam. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.meperidineSerious - Use Alternative (2)fluoxetine and meperidine both increase serotonin levels. Avoid or Use Alternate Drug. meperidine, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.metforminMonitor Closely (1)fluoxetine increases effects of metformin by pharmacodynamic synergism. Use Caution/Monitor.methadoneMonitor Closely (1)fluoxetine and methadone both increase QTc interval. Use Caution/Monitor.methamphetamineSerious - Use Alternative (1)fluoxetine will increase the level or effect of methamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.methylene blueContraindicated (1)methylene blue and fluoxetine both increase serotonin levels. Contraindicated. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue fluoxetine immediately and monitor for CNS toxicity. Fluoxetine may be resumed 24 hours after last methylene blue dose or after 5 weeks of monitoring, whichever comes first.methylenedioxymethamphetamineSerious - Use Alternative (1)fluoxetine increases toxicity of methylenedioxymethamphetamine by decreasing elimination. Contraindicated.methylphenidate transdermalMonitor Closely (1)methylphenidate transdermal will increase the level or effect of fluoxetine by decreasing metabolism. Modify Therapy/Monitor Closely. Consider decreasing the dose of these drugs when given coadministered with methylphenidate. Monitor for drug toxiticities when initiating or discontinuing methylphenidate. metoclopramideSerious - Use Alternative (1)metoclopramide and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug. Additive effects; increased risk for serotonin syndrome, neuroleptic malignant syndrome, dystonia, or other extrapyramidal reactionsmetoclopramide intranasalSerious - Use Alternative (2)fluoxetine will increase the level or effect of metoclopramide intranasal by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Concurrent use of metoclopramide intranasal and strong CYP2D6 inhibitors is not recommended since the metoclopramide intranasal dose cannot be adjusted. fluoxetine, 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.metoprololSerious - Use Alternative (1)fluoxetine will increase the level or effect of metoprolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.mexiletineSerious - Use Alternative (1)fluoxetine will increase the level or effect of mexiletine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.midazolam intranasalMonitor Closely (2)fluoxetine 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, fluoxetine. 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.mifepristoneMonitor Closely (1)mifepristone, fluoxetine. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.milnacipranSerious - Use Alternative (1)fluoxetine and milnacipran both increase serotonin levels. Avoid or Use Alternate Drug.mipomersenMonitor Closely (1)mipomersen, fluoxetine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Both drugs have potential to increase hepatic enzymes; monitor LFTs.mirabegronMonitor Closely (1)mirabegron will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.mirtazapineMonitor Closely (1)fluoxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)mirtazapine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.mobocertinibSerious - Use Alternative (1)mobocertinib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.morphineMonitor Closely (1)fluoxetine and morphine both increase serotonin levels. Modify Therapy/Monitor Closely.Serious - Use Alternative (2)fluoxetine will increase the level or effect of morphine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. morphine, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.moxifloxacinMonitor Closely (1)fluoxetine and moxifloxacin both increase QTc interval. Modify Therapy/Monitor Closely.nabumetoneMonitor Closely (1)fluoxetine, nabumetone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.naproxenMonitor Closely (1)fluoxetine, naproxen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.naratriptanMonitor Closely (1)naratriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)fluoxetine, naratriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.nateglinideMonitor Closely (1)fluoxetine will increase the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.nebivololSerious - Use Alternative (1)fluoxetine will increase the level or effect of nebivolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.nefazodoneSerious - Use Alternative (1)fluoxetine and nefazodone both increase serotonin levels. Avoid or Use Alternate Drug.netupitant/palonosetronSerious - Use Alternative (1)netupitant/palonosetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.nifedipineMonitor Closely (1)fluoxetine will increase the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Consider initiating nifedipine at the lowest dose available if given concomitantly with this medicationnilotinibMonitor Closely (1)fluoxetine and nilotinib both increase QTc interval. Modify Therapy/Monitor Closely.Minor (1)nilotinib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.nitisinoneMonitor Closely (1)nitisinone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Nitisinone inhibits CYP2C9. Caution if CYP2C9 substrate coadministered, particularly those with a narrow therapeutic index.nortriptylineMonitor Closely (1)nortriptyline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (2)fluoxetine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug. fluoxetine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.octreotideMonitor Closely (1)fluoxetine and octreotide both increase QTc interval. Modify Therapy/Monitor Closely.octreotide (Antidote)Monitor Closely (1)fluoxetine and octreotide (Antidote) both increase QTc interval. Modify Therapy/Monitor Closely.ofloxacinMonitor Closely (1)fluoxetine and ofloxacin both increase QTc interval. Use Caution/Monitor.olanzapineMonitor Closely (1)olanzapine and fluoxetine both increase QTc interval. Use Caution/Monitor.oliceridineMonitor Closely (2)fluoxetine will increase the level or effect of oliceridine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. If concomitant use is necessary, may require less frequent oliceridine dosing. Closely monitor for respiratory depression and sedation and titrate subsequent doses accordingly. If inhibitor is discontinued, consider increase oliceridine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. fluoxetine, oliceridine. Either increases toxicity of the other by serotonin levels. Modify Therapy/Monitor Closely.olodaterol inhaledMonitor Closely (1)fluoxetine and olodaterol inhaled both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular systemolopatadine intranasalSerious - Use Alternative (1)fluoxetine 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)fluoxetine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.ondansetronSerious - Use Alternative (2)fluoxetine 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. ondansetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.osilodrostatMonitor Closely (1)osilodrostat and fluoxetine both increase QTc interval. Use Caution/Monitor.osimertinibMonitor Closely (1)osimertinib and fluoxetine both increase QTc