decrease cholinergic effects/transmission. Use Caution/Monitor. doxepin and solifenacin both increase QTc interval. Use Caution/Monitor.sorafenibMonitor Closely (1)doxepin and sorafenib both increase QTc interval. Use Caution/Monitor.sotalolContraindicated (1)doxepin and sotalol both increase QTc interval. Contraindicated.St John's WortSerious - Use Alternative (1)doxepin and St John's Wort both increase serotonin levels. Avoid or Use Alternate Drug.stiripentolMonitor Closely (2)stiripentol, doxepin. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence. stiripentol, doxepin. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.succinylcholineMonitor Closely (1)succinylcholine increases and doxepin decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.sufentanilMonitor Closely (1)sufentanil and doxepin both increase sedation. Use Caution/Monitor.sufentanil SLMonitor Closely (1)sufentanil SL, doxepin. 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.sulfamethoxazoleMonitor Closely (1)doxepin and sulfamethoxazole both increase QTc interval. Modify Therapy/Monitor Closely.Minor (1)sulfamethoxazole decreases levels of doxepin by unspecified interaction mechanism. Minor/Significance Unknown.sumatriptanMonitor Closely (1)sumatriptan and doxepin both increase serotonin levels. Modify Therapy/Monitor Closely.sumatriptan intranasalMonitor Closely (1)sumatriptan intranasal and doxepin both increase serotonin levels. Modify Therapy/Monitor Closely.sunitinibMonitor Closely (1)doxepin and sunitinib both increase QTc interval. Use Caution/Monitor.suvorexantMonitor Closely (1)suvorexant and doxepin both increase sedation. Modify Therapy/Monitor Closely. Dosage adjustments of suvorexant and concomitant CNS depressants may be necessarytacrolimusMonitor Closely (1)doxepin and tacrolimus both increase QTc interval. Use Caution/Monitor.tapentadolMonitor Closely (2)doxepin and tapentadol both increase serotonin levels. Modify Therapy/Monitor Closely. tapentadol and doxepin both increase sedation. Use Caution/Monitor.tedizolidSerious - Use Alternative (1)tedizolid, doxepin. Either increases effects of the other by Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. both increase serotonin levels; increased risk of serotonin syndrome.telavancinMonitor Closely (1)doxepin and telavancin both increase QTc interval. Modify Therapy/Monitor Closely.temazepamMonitor Closely (1)temazepam and doxepin both increase sedation. Use Caution/Monitor.terbinafineMonitor Closely (1)terbinafine will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Assess need to reduce dose of CYP2D6-metabolized drug.terbutalineMonitor Closely (1)doxepin increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)doxepin, terbutaline. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.teriflunomideMonitor Closely (1)teriflunomide decreases levels of doxepin by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.tetrabenazineMonitor Closely (1)tetrabenazine and doxepin both increase QTc interval. Use Caution/Monitor.thioridazineContraindicated (1)thioridazine will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated.Monitor Closely (1)thioridazine and doxepin both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)thioridazine and doxepin both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)doxepin, thioridazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. doxepin, thioridazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.thiothixeneMonitor Closely (2)thiothixene and doxepin both increase sedation. Use Caution/Monitor. doxepin and thiothixene both increase QTc interval. Use Caution/Monitor.thyroid desiccatedMonitor Closely (1)thyroid desiccated increases effects of doxepin by Other (see comment). Use Caution/Monitor. Comment: Increased catecholamine receptor sensitivity; may increase CNS and cardiovascular effects, including arrhythmias.tiotropiumMonitor Closely (1)tiotropium and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor.tipranavirMinor (1)tipranavir will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.tolazamideMinor (1)doxepin increases effects of tolazamide by pharmacodynamic synergism. Minor/Significance Unknown.tolbutamideMinor (1)doxepin increases effects of tolbutamide by pharmacodynamic synergism. Minor/Significance Unknown.tolterodineMonitor Closely (1)tolterodine and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor.topiramateMonitor Closely (1)doxepin and topiramate both increase sedation. Modify Therapy/Monitor Closely.toremifeneSerious - Use Alternative (1)doxepin 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.tramadolMonitor Closely (2)doxepin and tramadol both increase serotonin levels. Modify Therapy/Monitor Closely. tramadol and doxepin both increase sedation. Use Caution/Monitor.tranylcypromineContraindicated (1)tranylcypromine and doxepin both increase serotonin levels. Contraindicated.trazodoneMonitor Closely (2)doxepin and trazodone both decrease cholinergic effects/transmission. Use Caution/Monitor. doxepin and trazodone both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)doxepin and trazodone both increase QTc interval. Avoid or Use Alternate Drug. trazodone and doxepin both increase serotonin levels. Avoid or Use Alternate Drug.triazolamMonitor Closely (1)triazolam and doxepin both increase sedation. Use Caution/Monitor.triclabendazoleMonitor Closely (1)doxepin and triclabendazole both increase QTc interval. Use Caution/Monitor.triclofosMonitor Closely (1)triclofos and doxepin both increase sedation. Use Caution/Monitor.trifluoperazineMonitor Closely (1)trifluoperazine and doxepin both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)trifluoperazine and doxepin both increase QTc interval. Avoid or Use Alternate Drug.Minor (2)doxepin, trifluoperazine. Either increases levels of the other by decreasing metabolism. Minor/Significance Unknown. Additive anticholinergic effects. doxepin, trifluoperazine. Either increases levels of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive anticholinergic effects.trihexyphenidylMonitor Closely (1)trihexyphenidyl and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor. Potential for additive anticholinergic effects.trimethoprimMonitor Closely (1)doxepin and trimethoprim both increase QTc interval. Modify Therapy/Monitor Closely.trimipramineMonitor Closely (2)doxepin and trimipramine both decrease cholinergic effects/transmission. Use Caution/Monitor. doxepin and trimipramine both increase sedation. Use Caution/Monitor.Serious - Use Alternative (2)doxepin and trimipramine both increase QTc interval. Avoid or Use Alternate Drug. doxepin and trimipramine both increase serotonin levels. Avoid or Use Alternate Drug.triprolidineMonitor Closely (1)triprolidine and doxepin both increase sedation. Use Caution/Monitor.triptorelinMonitor Closely (1)doxepin and triptorelin both increase QTc interval. Use Caution/Monitor.tropisetronMonitor Closely (1)doxepin and tropisetron both increase QTc interval. Modify Therapy/Monitor Closely.trospium chlorideMonitor Closely (1)trospium chloride and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor.tucatinibSerious - Use Alternative (1)tucatinib will increase the level or effect of doxepin 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.umeclidinium bromide/vilanterol inhaledMonitor Closely (1)doxepin and umeclidinium bromide/vilanterol inhaled both decrease QTc interval. Use Caution/Monitor.Serious - Use Alternative (1)doxepin and umeclidinium bromide/vilanterol inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Exercise extreme caution if vilanterol coadministered with MAOIs or TCAs, or within 2 weeks of discontinuation of these drugs; adrenergic agonist effects on the cardiovascular system may be potentiatedvalbenazineMonitor Closely (1)valbenazine and doxepin both increase QTc interval. Use Caution/Monitor.valerianMonitor Closely (1)valerian and doxepin both increase sedation. Use Caution/Monitor.vandetanibSerious - Use Alternative (1)doxepin, vandetanib. Either increases toxicity of the other by QTc interval. Avoid or Use Alternate Drug. Avoid coadministration with drugs known to prolong QT interval; if a drug known to prolong QT interval must be used, more frequent ECG monitoring is recommended.vardenafilMonitor Closely (1)doxepin and vardenafil both increase QTc interval. Use Caution/Monitor.vasopressinMinor (1)doxepin increases effects of vasopressin by pharmacodynamic synergism. Minor/Significance Unknown.vecuroniumMonitor Closely (1)vecuronium and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor.vemurafenibMonitor Closely (1)doxepin and vemurafenib both increase QTc interval. Use Caution/Monitor.venlafaxineMonitor Closely (1)doxepin and venlafaxine both increase QTc interval. Modify Therapy/Monitor Closely.Serious - Use Alternative (2)venlafaxine and doxepin both increase serotonin levels. Avoid or Use Alternate Drug. venlafaxine will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.verapamilMinor (1)verapamil increases levels of doxepin by decreasing metabolism. Minor/Significance Unknown.vilanterol/fluticasone furoate inhaledSerious - Use Alternative (1)doxepin and vilanterol/fluticasone furoate inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Exercise extreme caution if vilanterol coadministered with MAOIs or TCAs, or within 2 weeks of discontinuation of these drugs; adrenergic agonist effects on the cardiovascular system may be potentiatedvilazodoneSerious - Use Alternative (1)doxepin, 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. .vildagliptinMinor (1)doxepin increases effects of vildagliptin by pharmacodynamic synergism. Minor/Significance Unknown.voclosporinMonitor Closely (1)doxepin and voclosporin both increase QTc interval. Use Caution/Monitor.voriconazoleMonitor Closely (1)doxepin and voriconazole both increase QTc interval. Modify Therapy/Monitor Closely.vorinostatMonitor Closely (1)doxepin and vorinostat both increase QTc interval. Use Caution/Monitor.vortioxetineSerious - Use Alternative (1)doxepin, vortioxetine. Either increases effects of the other by serotonin levels. Avoid or Use Alternate Drug.xylometazolineMonitor Closely (1)doxepin increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)doxepin, xylometazoline. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.yohimbeSerious - Use Alternative (1)yohimbe, doxepin. Mechanism: unspecified interaction mechanism. Contraindicated. May cause increase or decrease in blood pressure.yohimbineMonitor Closely (1)doxepin increases and yohimbine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.Serious - Use Alternative (1)doxepin, yohimbine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.ziconotideMonitor Closely (1)doxepin and ziconotide both increase sedation. Use Caution/Monitor.ziprasidoneMonitor Closely (1)ziprasidone and doxepin both increase sedation. Use Caution/Monitor.Serious - Use Alternative (1)doxepin and ziprasidone both increase QTc interval. Avoid or Use Alternate Drug.zolmitriptanMonitor Closely (1)zolmitriptan and doxepin both increase serotonin levels. Modify Therapy/Monitor Closely.zolpidemMinor (1)zolpidem, doxepin. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive CNS depression. Frequency Not Defined Sedation, fatigue, weakness, lethargy Dry mouth Constipation Blurred vision Headache Agitation Insomnia Anxiety Nausea, vomiting Sweating Confusion, extrapyramidal symptoms (EPS), dizziness, paresthesia Orthostatic hypotension, ECG changes, tachycardia Increased LFTs Tinnitus Sexual dysfunction Rash Seizure Agranulocytosis Thrombocytopenia Eosinophilia Leukopenia SIADH Black Box Warnings In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (<24 years) taking antidepressants for major depressive disorders and other psychiatric illnesses This increase was not seen in patients >24 years; a slight decrease in suicidal thinking was seen in adults >65 years In children and young adults, risks must be weighed against the benefits of taking antidepressants Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during initial 1-2 months of therapy and dosage adjustments The patient’s family should communicate any abrupt changes in behavior to the healthcare provider Worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy This drug is not approved for use in pediatric patientsContraindications Hypersensitivity Untreated narrow-angle glaucoma Severe urinary retention Within 14 days of MAO inhibitors Cautions Use caution in BPH, urinary retention, decreased GI motility, hyperthyroidism, brain tumor, diabetes, hepatic impairment, cardiovascular disease, mania/hypomania, respiratory disease, and seizure disorders Clinical worsening and suicidal ideation may occur despite medication in adolescents and young adults (aged 18-24 years) Risk of anticholinergic side effects Risk of mydriasis; may trigger angle closure attack in patients with angle closure glaucoma with anatomically narrow angles without a patent iridectomy CNS depressant; can impair alertness and motor coordination; avoid use with other CNS depressants (eg, alcohol) Overdose may cause EKG QRS widening and risk of dysrhythmias Protect capsules and oral concentrate from direct sunlight Prescriptions should be written for smallest quantity consistent with good patient care; patient's family or caregiver should alert healthcare professional about emergence of suicidality and related behaviors including agitation, panic attacks, irritability, impulsivity, mania, and insomnia or if worsening depression or psychosis occurs Anticholinergic effects including blurred vision, urinary retention, xerostomia, and constipation may occur Neuropsychiatric symptoms may occur unpredictably including anxiety and psychosis Bone fracture reported with use of antidepressant therapy; consider possibility of fracture if patient presents with unexplained bone pain, joint tenderness, bruising or swelling May cause orthostatic hypotension; use caution in patients at risk of this effect or that may not tolerate hypotensive episodes (eg, hypovolemia, cardiovascular or cerebrovascular disease and others) Sleep related activities including sleep driving, eating food, cooking, making phone calls reported; discontinue therapy if patient reports sleep-related episodes Possibility of EPS and neuroleptic malignant syndrome (NMS) May cause confusion in the elderly; avoid doses >6 mg/day Pregnancy Available data from published epidemiologic studies and postmarketing reports have not