sedation. Use Caution/Monitor.glycopyrrolatethiothixene increases effects of glycopyrrolate by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.glycopyrrolate inhaledglycopyrrolate inhaled decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.glycopyrrolate inhaled decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of glycopyrrolate inhaled by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.glycopyrronium tosylate topicalglycopyrronium tosylate topical, thiothixene. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration of glycopyrronium tosylate topical with other anticholinergic medications may result in additive anticholinergic adverse effects.guanfacineguanfacine, thiothixene. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects; potential delirium.haloperidolhaloperidol and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.haloperidol and thiothixene both increase sedation. Use Caution/Monitor.haloperidol and thiothixene both increase QTc interval. Use Caution/Monitor.henbanehenbane decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.henbane decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of henbane by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.homatropinehomatropine decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.homatropine decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of homatropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.hydromorphonehydromorphone and thiothixene both increase sedation. Use Caution/Monitor.hydroxyzinehydroxyzine and thiothixene both increase sedation. Use Caution/Monitor.hyoscyaminehyoscyamine decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.hyoscyamine decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of hyoscyamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.hyoscyamine spraythiothixene increases effects of hyoscyamine spray by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.hyoscyamine spray decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.hyoscyamine spray decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.iloperidoneiloperidone and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.iloperidone and thiothixene both increase sedation. Use Caution/Monitor.imipraminethiothixene and imipramine both increase sedation. Use Caution/Monitor.incobotulinumtoxinAthiothixene increases effects of incobotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.indacaterol, inhaledindacaterol, inhaled, thiothixene. QTc interval. Use Caution/Monitor. Drugs that are known to prolong the QTc interval may have an increased the risk of ventricular arrhythmias.ipratropiumipratropium decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.ipratropium decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of ipratropium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.isoproterenolthiothixene increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.ketamineketamine and thiothixene both increase sedation. Use Caution/Monitor.ketotifen, ophthalmicthiothixene and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.lasmiditanlasmiditan, thiothixene. 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.lemborexantlemborexant, thiothixene. 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.levalbuterolthiothixene increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.levomilnacipranlevomilnacipran, thiothixene. 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).levorphanollevorphanol and thiothixene both increase sedation. Use Caution/Monitor.linezolidlinezolid, thiothixene. 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).lisdexamfetaminethiothixene increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.lithiumlithium, thiothixene. 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).lithium and thiothixene both increase QTc interval. Use Caution/Monitor.lofepraminethiothixene and lofepramine both increase sedation. Use Caution/Monitor.lofexidinethiothixene and lofexidine both increase sedation. Use Caution/Monitor.loprazolamloprazolam and thiothixene both increase sedation. Use Caution/Monitor.lorazepamlorazepam and thiothixene both increase sedation. Use Caution/Monitor.lorcaserinlorcaserin, thiothixene. 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).lormetazepamlormetazepam and thiothixene both increase sedation. Use Caution/Monitor.loxapineloxapine and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.loxapine and thiothixene both increase sedation. Use Caution/Monitor.loxapine inhaledloxapine inhaled and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.loxapine inhaled and thiothixene both increase sedation. Use Caution/Monitor.lurasidonelurasidone, thiothixene. 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.maprotilinethiothixene and maprotiline both increase sedation. Use Caution/Monitor.maravirocmaraviroc, thiothixene. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.marijuanathiothixene and marijuana both increase sedation. Use Caution/Monitor.meclizinemeclizine decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.meclizine decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of meclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.melatoninthiothixene and melatonin both increase sedation. Use Caution/Monitor.meperidinemeperidine and thiothixene both increase sedation. Use Caution/Monitor.meperidine, thiothixene. 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).meprobamatethiothixene and meprobamate both increase sedation. Use Caution/Monitor.metaproterenolthiothixene increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.metaxalonemetaxalone and thiothixene both increase sedation. Use Caution/Monitor.methadonemethadone and thiothixene both increase sedation. Use Caution/Monitor.methadone, thiothixene. 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).methamphetaminethiothixene increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methocarbamolmethocarbamol and thiothixene both increase sedation. Use Caution/Monitor.methscopolaminemethscopolamine decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.methscopolamine decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of methscopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.methylenedioxymethamphetaminethiothixene increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.methylergonovinemethylergonovine, thiothixene. 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).methylphenidatethiothixene 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.metoclopramidethiothixene and metoclopramide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.midazolammidazolam and thiothixene both increase sedation. Use Caution/Monitor.midazolam intranasalmidazolam intranasal, thiothixene. 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.midodrinethiothixene increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.mifepristonemifepristone, thiothixene. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.milnacipranmilnacipran, thiothixene. 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).mirtazapinethiothixene and mirtazapine both increase sedation. Use Caution/Monitor.modafinilthiothixene increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.morphinemorphine and thiothixene both increase sedation. Use Caution/Monitor.motherwortthiothixene and motherwort both increase sedation. Use Caution/Monitor.moxonidinethiothixene and moxonidine both increase sedation. Use Caution/Monitor.nabilonethiothixene and nabilone both increase sedation. Use Caution/Monitor.nalbuphinenalbuphine and thiothixene both increase sedation. Use Caution/Monitor.naratriptannaratriptan, thiothixene. 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).norepinephrinethiothixene increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.nortriptylinethiothixene and nortriptyline both increase sedation. Use Caution/Monitor.olanzapineolanzapine and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.olanzapine and thiothixene both increase sedation. Use Caution/Monitor.oliceridineoliceridine, thiothixene. 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.olodaterol inhaledthiothixene and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. Drugs that prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk of ventricular arrhythmiasonabotulinumtoxinAonabotulinumtoxinA decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.onabotulinumtoxinA decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of onabotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.opium tinctureopium tincture and thiothixene both increase sedation. Use Caution/Monitor.orphenadrineorphenadrine and thiothixene both increase sedation. Use Caution/Monitor.osimertinibosimertinib and thiothixene both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.oxazepamoxazepam and thiothixene both increase sedation. Use Caution/Monitor.oxybutyninoxybutynin decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.oxybutynin decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of oxybutynin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.oxybutynin topicaloxybutynin topical decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.oxybutynin topical decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of oxybutynin topical by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.oxybutynin transdermaloxybutynin transdermal decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.oxybutynin transdermal decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of oxybutynin transdermal by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.oxycodoneoxycodone and thiothixene both increase sedation. Use Caution/Monitor.oxymorphoneoxymorphone and thiothixene both increase sedation. Use Caution/Monitor.ozanimodozanimod and thiothixene both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.paliperidonepaliperidone and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.paliperidone and thiothixene both increase sedation. Use Caution/Monitor.pancuroniumpancuronium decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both