both increase serotonin levels. Avoid or Use Alternate Drug.indapamideindapamide and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.iobenguane I 131venlafaxine 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.isofluraneisoflurane and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.ivosidenibivosidenib will decrease the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.levomilnacipranlevomilnacipran and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.levorphanolvenlafaxine and levorphanol both increase serotonin levels. Avoid or Use Alternate Drug. May cause serotonin syndromelinezolidlinezolid and venlafaxine 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.lofepraminevenlafaxine and lofepramine both increase serotonin levels. Avoid or Use Alternate Drug.lonafarniblonafarnib will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with sensitive CYP3A substrates. If coadministration unavoidable, monitor for adverse reactions and reduce CYP3A substrate dose in accordance with product labeling.lorcaserinvenlafaxine and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.maprotilinevenlafaxine and maprotiline both increase serotonin levels. Avoid or Use Alternate Drug.mefloquinemefloquine increases toxicity of venlafaxine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.meperidinevenlafaxine and meperidine both increase serotonin levels. Avoid or Use Alternate Drug.methylene bluemethylene blue and venlafaxine 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.metoclopramidemetoclopramide and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug. Additive effects; increased risk for serotonin syndrome, neuroleptic malignant syndrome, dystonia, or other extrapyramidal reactionsmilnacipranmilnacipran and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.mirtazapinemirtazapine and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.nalbuphinevenlafaxine and nalbuphine both increase serotonin levels. Avoid or Use Alternate Drug. May cause serotonin syndromenefazodonenefazodone and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.nefazodone will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.netupitant/palonosetronnetupitant/palonosetron, venlafaxine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.nortriptylinevenlafaxine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.venlafaxine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.ondansetronondansetron, venlafaxine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.opium tincturevenlafaxine and opium tincture both increase serotonin levels. Avoid or Use Alternate Drug. May cause serotonin syndromeoxaliplatinoxaliplatin and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.ozanimodozanimod increases toxicity of venlafaxine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.palonosetronpalonosetron, venlafaxine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.paroxetineparoxetine and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.pentamidinepentamidine and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.perphenazineperphenazine and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.phenterminevenlafaxine, phentermine. Either increases toxicity of the other by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of serotonin syndrome.pimozidepimozide and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.procainamideprocainamide and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.promethazinevenlafaxine will increase the level or effect of promethazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.protriptylinevenlafaxine and protriptyline both increase serotonin levels. Avoid or Use Alternate Drug.pseudoephedrinevenlafaxine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.quinidinequinidine and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.rasagilinerasagiline and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug. Severe CNS toxicity associated with hyperpyrexia has been reported with the combined treatment of an antidepressant and rasagiline. Avoid combination within 14 days of MAOI use.remifentanilvenlafaxine and remifentanil both decrease serotonin levels. Avoid or Use Alternate Drug. May cause serotonin syndromeribociclibribociclib will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.saquinavirsaquinavir, venlafaxine. Either increases toxicity of the other by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. May increase risk for QT prolongation.selegiline transdermalselegiline transdermal and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.sertralinesertraline and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.sertraline and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.sevofluranesevoflurane and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.siponimodsiponimod and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.sotalolsotalol and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.St John's Wortvenlafaxine and St John's Wort both increase serotonin levels. Avoid or Use Alternate Drug.sufentanilvenlafaxine and sufentanil both decrease serotonin levels. Avoid or Use Alternate Drug. May cause serotonin syndrometedizolidtedizolid, venlafaxine. Either increases effects of the other by Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. both increase serotonin levels; increased risk of serotonin syndrome.tetrabenazinetetrabenazine and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.thioridazinevenlafaxine will increase the level or effect of thioridazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.thioridazine and venlafaxine both increase QTc interval. Avoid or Use Alternate Drug.toremifenevenlafaxine and toremifene both increase QTc interval. Avoid or Use Alternate Drug. Concurrent use of toremifene with agents causing QT prolongation should be avoided. If concomitant use is required it's recommended that toremifene be interrupted. If interruption not possible, patients requiring therapy with a drug that prolongs QT should be closely monitored. ECGs should be obtained for high risk patients.trazodonetrazodone and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.trimipraminevenlafaxine and trimipramine both increase serotonin levels. Avoid or Use Alternate Drug.tucatinibtucatinib will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.vilazodonevenlafaxine, vilazodone. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug. Concomitant therapy should be discontinued immediately if signs or symptoms of serotonin syndrome emerge and supportive symptomatic treatment should be initiated. .voriconazolevoriconazole will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.vortioxetinevenlafaxine, vortioxetine. Either increases effects of the other by serotonin levels. Avoid or Use Alternate Drug.voxelotorvoxelotor will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.Monitor Closely (226)5-HTPvenlafaxine and 5-HTP both increase serotonin levels. Modify Therapy/Monitor Closely.abirateroneabiraterone increases levels of venlafaxine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Avoid coadministration of abiraterone with substrates of CYP2D6. If alternative therapy cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate.aceclofenacvenlafaxine, aceclofenac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.acemetacinvenlafaxine, acemetacin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.almotriptanalmotriptan and venlafaxine both increase serotonin levels. Modify Therapy/Monitor Closely.amifampridinevenlafaxine increases toxicity of amifampridine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Amifampridine can cause seizures. Coadministration with drugs that lower seizure threshold may increase this risk.amitriptylineamitriptyline and venlafaxine both increase QTc interval. Modify Therapy/Monitor Closely.amoxapineamoxapine and venlafaxine both increase QTc interval. Modify Therapy/Monitor Closely.aripiprazolevenlafaxine will increase the level or effect of aripiprazole by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.venlafaxine, aripiprazole. 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).artemether/lumefantrineartemether/lumefantrine and venlafaxine both increase QTc interval. Modify Therapy/Monitor Closely.asenapinevenlafaxine, asenapine. 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).aspirinvenlafaxine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.aspirin rectalvenlafaxine, aspirin rectal. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.aspirin/citric acid/sodium bicarbonatevenlafaxine, aspirin/citric acid/sodium bicarbonate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.atomoxetinevenlafaxine will increase the level or effect of atomoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.benzhydrocodone/acetaminophenvenlafaxine will increase the level or effect of benzhydrocodone/acetaminophen by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone [benzhydrocodone is prodrug of hydrocodone]) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone.benzhydrocodone/acetaminophen, venlafaxine. 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.buprenorphine subdermal implantvenlafaxine, buprenorphine subdermal implant. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Concomitant use could result in life-threatening serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation, and during dose adjustment of the serotonergic drug. Discontinue buprenorphine if serotonin syndrome is suspected.buprenorphine, long-acting injectionvenlafaxine, buprenorphine, long-acting injection. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Concomitant use could result in life-threatening serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation, and during dose adjustment of the serotonergic drug. Discontinue buprenorphine if serotonin syndrome is suspected.bupropionbupropion will increase the level or effect of venlafaxine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.cariprazinevenlafaxine, cariprazine. 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).carvedilolvenlafaxine will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.celecoxibvenlafaxine, celecoxib. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.chloramphenicolchloramphenicol will increase the level or effect of venlafaxine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.chlorpromazinevenlafaxine will increase the level or effect of chlorpromazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.chlorpromazine and venlafaxine both increase QTc interval. Modify