the level or effect of fesoterodine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.fexinidazoleMonitor Closely (1)fexinidazole will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.fish oil triglyceridesMonitor Closely (1)fish oil triglycerides will increase the level or effect of duloxetine by anticoagulation. Use Caution/Monitor. Prolonged bleeding reported in patients taking antiplatelet agents or anticoagulants and oral omega-3 fatty acids. Periodically monitor bleeding time in patients receiving fish oil triglycerides and concomitant antiplatelet agents or anticoagulants.flecainideMinor (1)duloxetine will increase the level or effect of flecainide by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.fluoxetineSerious - Use Alternative (2)duloxetine and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug. fluoxetine will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.Minor (1)duloxetine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.fluphenazineMinor (1)duloxetine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.flurbiprofenMonitor Closely (1)duloxetine, flurbiprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.fluvoxamineSerious - Use Alternative (2)fluvoxamine will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. fluvoxamine and duloxetine both increase serotonin levels. Avoid or Use Alternate Drug.frovatriptanMonitor Closely (1)frovatriptan and duloxetine both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)duloxetine, frovatriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.furosemideMinor (1)furosemide, duloxetine. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Possible additive hyponatremia.gabapentinMonitor Closely (1)gabapentin, duloxetine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.gabapentin enacarbilMonitor Closely (1)gabapentin enacarbil, duloxetine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.galantamineMinor (1)duloxetine will increase the level or effect of galantamine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.ganaxoloneMonitor Closely (1)duloxetine and ganaxolone both increase sedation. Use Caution/Monitor.givosiranSerious - Use Alternative (2)givosiran will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling. givosiran will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP2D6 substrates with givosiran. If unavoidable, decrease the CYP2D6 substrate dosage in accordance with approved product labeling.glofitamabMonitor Closely (1)glofitamab, duloxetine. affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Glofitamab causes release of cytokines that may suppress activity of CYP enzymes, resulting in increased exposure of CYP substrates. For certain CYP substrates, minimal changes in their concentration may lead to serious adverse reactions. If needed, modify therapy as recommended in the substrate's prescribing information. .granisetronSerious - Use Alternative (1)granisetron, duloxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.green teaMonitor Closely (1)green tea, duloxetine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.haloperidolMinor (2)duloxetine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown. haloperidol will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.hydrocodoneMonitor Closely (2)hydrocodone, duloxetine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration of drugs that affect the serotonergic neurotransmitter system may result in serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment. duloxetine will increase the level or effect of hydrocodone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone.hydromorphoneMonitor Closely (1)duloxetine will increase the level or effect of hydromorphone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.ibrutinibMonitor Closely (1)ibrutinib will increase the level or effect of duloxetine by anticoagulation. Use Caution/Monitor. Ibrutinib may increase the risk of hemorrhage in patients receiving antiplatelet or anticoagulant therapies and monitor for signs of bleeding. ibuprofenMonitor Closely (1)duloxetine, ibuprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.ibuprofen IVMonitor Closely (1)duloxetine, ibuprofen IV. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.iloperidoneMinor (1)duloxetine will increase the level or effect of iloperidone by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.imatinibMonitor Closely (1)imatinib will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.imipramineMonitor Closely (1)duloxetine will increase the level or effect of imipramine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely.Serious - Use Alternative (1)duloxetine and imipramine both increase serotonin levels. Avoid or Use Alternate Drug.indomethacinMonitor Closely (1)duloxetine, indomethacin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.iobenguane I 123Contraindicated (1)duloxetine decreases effects of iobenguane I 123 by pharmacodynamic antagonism. Contraindicated. If clinically appropriate, discontinue drugs that decrease uptake of NE for at least 5 half-lives; may cause false-negative imaging results.iobenguane I 131Serious - Use Alternative (1)duloxetine will decrease the level or effect of iobenguane I 131 by Other (see comment). Avoid or Use Alternate Drug. Based on the mechanism of action of iobenguane, drugs that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells, and thus, reduce iobenguane efficacy. Discontinue interfering drugs for at least 5 half-lives before administration of either the dosimetry or an iobenguane dose. Do not administer these drugs until at least 7 days after each iobenguane dose.isocarboxazidContraindicated (1)isocarboxazid and duloxetine both increase serotonin levels. Contraindicated.isoniazidMonitor Closely (2)isoniazid will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. duloxetine and isoniazid both increase serotonin levels. Modify Therapy/Monitor Closely.ketoprofenMonitor Closely (1)duloxetine, ketoprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.ketorolacMonitor Closely (1)duloxetine, ketorolac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.ketorolac intranasalMonitor Closely (1)duloxetine, ketorolac intranasal. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.L-tryptophanMonitor Closely (1)duloxetine and L-tryptophan both increase serotonin levels. Modify Therapy/Monitor Closely.lasmiditanMonitor Closely (2)lasmiditan, duloxetine. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions. duloxetine increases effects of lasmiditan by serotonin levels. Use Caution/Monitor. Coadministration may increase risk of serotonin syndrome.lemborexantMonitor Closely (1)lemborexant, duloxetine. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.leniolisibSerious - Use Alternative (1)leniolisib will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid leniolisib with CYP1A2 substrates that have a narrow therapeutic indexlevomilnacipranSerious - Use Alternative (1)duloxetine and levomilnacipran both increase serotonin levels. Avoid or Use Alternate Drug.linezolidSerious - Use Alternative (1)linezolid and duloxetine both increase serotonin levels. Avoid or Use Alternate Drug. 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 2 weeks of monitoring, whichever comes first.lisdexamfetamineMonitor Closely (1)duloxetine, 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 (1)duloxetine and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.Minor (1)duloxetine, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.lofepramineMonitor Closely (1)duloxetine will increase the level or effect of lofepramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)duloxetine and lofepramine both increase serotonin levels. Avoid or Use Alternate Drug.lonapegsomatropinMonitor Closely (1)lonapegsomatropin will decrease the level or effect of duloxetine 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 substratesloratadineMinor (1)duloxetine will increase the level or effect of loratadine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.lorcaserinMonitor Closely (1)lorcaserin will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)duloxetine and lorcaserin both increase sedation. Avoid or Use Alternate Drug.lornoxicamMonitor Closely (1)duloxetine, 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.lsdMonitor Closely (1)duloxetine and lsd both increase serotonin levels. Modify Therapy/Monitor Closely.lumefantrineSerious - Use Alternative (1)lumefantrine will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.lurasidoneMonitor Closely (1)lurasidone, duloxetine. 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.maprotilineSerious - Use Alternative (1)duloxetine and maprotiline both increase serotonin levels. Avoid or Use Alternate Drug.maravirocMonitor Closely (1)maraviroc will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.marijuanaMonitor Closely (1)marijuana will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.meclofenamateMonitor Closely (1)duloxetine, 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)duloxetine, 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.meloxicamMonitor Closely (1)duloxetine, 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 (1)duloxetine and meperidine both increase serotonin levels. Avoid or Use Alternate Drug.methamphetamineMonitor Closely (1)duloxetine will increase the level or effect of methamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely.methylene blueSerious - Use Alternative (1)methylene blue and duloxetine both increase serotonin levels. Avoid or Use Alternate Drug. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last methylene blue dose or after 2 weeks of monitoring, whichever comes first.metoclopramideSerious - Use Alternative (1)metoclopramide and duloxetine 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 (1)duloxetine, 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.metoprololMonitor Closely (1)duloxetine will increase the level or effect of metoprolol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.mexiletineMonitor Closely (1)duloxetine will increase the level or effect of mexiletine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)mexiletine will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Contraindicated.midazolam intranasalMonitor Closely (1)midazolam intranasal, duloxetine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.milnacipranSerious - Use Alternative (1)duloxetine and milnacipran both increase serotonin levels. Avoid or Use Alternate Drug.mirabegronMonitor Closely (1)mirabegron will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.mirtazapineMonitor Closely (1)duloxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.modafinilSerious - Use Alternative (1)modafinil will decrease the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Avoid