Hyoscyamine, methenamine, methylene blue, and sodium phosphate: Drug information

Drug Interactions

Acetylcholinesterase Inhibitors: May decrease therapeutic effects of Agents with Clinically Relevant Anticholinergic Effects. Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Acetylcholinesterase Inhibitors. Risk C: Monitor

Aclidinium: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid

Acrivastine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Agents with Blood Glucose Lowering Effects: Monoamine Oxidase Inhibitors may increase hypoglycemic effects of Agents with Blood Glucose Lowering Effects. Risk C: Monitor

Alcohol (Ethyl): May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Alosetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Alpha-/Beta-Agonists (Indirect-Acting): Monoamine Oxidase Inhibitors may increase hypertensive effects of Alpha-/Beta-Agonists (Indirect-Acting). While linezolid is expected to interact via this mechanism, management recommendations differ from other monoamine oxidase inhibitors. Refer to linezolid specific monographs for details. Risk X: Avoid

Alpha1-Agonists: Monoamine Oxidase Inhibitors may increase hypertensive effects of Alpha1-Agonists. While linezolid is expected to interact via this mechanism, management recommendations differ from other monoamine oxidase inhibitors. Refer to linezolid specific monographs for details. Risk X: Avoid

Amantadine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Amantadine: Urinary Acidifying Agents may decrease serum concentration of Amantadine. Risk C: Monitor

Amifampridine: Agents With Seizure Threshold Lowering Potential may increase neuroexcitatory and/or seizure-potentiating effects of Amifampridine. Risk C: Monitor

Amisulpride (Oral): Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Amisulpride (Oral). Specifically, the risk of seizures may be increased. Risk C: Monitor

Amphetamines: Monoamine Oxidase Inhibitors may increase hypertensive effects of Amphetamines. While linezolid and tedizolid may interact via this mechanism, management recommendations differ from other monoamine oxidase inhibitors. Refer to monographs specific to those agents for details. Risk X: Avoid

Antacids: May decrease serum concentration of Hyoscyamine. Management: Administer immediate release and sublingual oral hyoscyamine before meals, and antacids after meals, when these agents are given in combination. Risk D: Consider Therapy Modification

Antacids: May decrease therapeutic effects of Methenamine. Management: Consider avoiding the concomitant use of medications that alkalinize the urine, such as antacids, and methenamine. Monitor for decreased therapeutic effects of methenamine if used concomitant with antacids. Risk D: Consider Therapy Modification

Antiemetics (5HT3 Antagonists): May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Apraclonidine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Apraclonidine. Monoamine Oxidase Inhibitors may increase serum concentration of Apraclonidine. Risk X: Avoid

ARIPiprazole Lauroxil: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ARIPiprazole Lauroxil. Specifically, the risk of seizures may be increased. Risk C: Monitor

ARIPiprazole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ARIPiprazole. Specifically, the risk of seizures may be increased. Risk C: Monitor

Asenapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Asenapine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Atomoxetine: Monoamine Oxidase Inhibitors may increase neurotoxic (central) effects of Atomoxetine. Risk X: Avoid

Atropine (Ophthalmic): Monoamine Oxidase Inhibitors may increase hypertensive effects of Atropine (Ophthalmic). Risk X: Avoid

Avocado: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Bacillus clausii: Antibiotics may decrease therapeutic effects of Bacillus clausii. Management: Bacillus clausii should be taken in between antibiotic doses during concomitant therapy. Risk D: Consider Therapy Modification

BCG (Intravesical): Antibiotics may decrease therapeutic effects of BCG (Intravesical). Risk X: Avoid

BCG Vaccine (Immunization): Antibiotics may decrease therapeutic effects of BCG Vaccine (Immunization). Risk C: Monitor

Benperidol: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Benperidol. Risk C: Monitor

Benperidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Benperidol. Specifically, the risk of seizures may be increased. Risk C: Monitor

Benzhydrocodone: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Management: The use of benzhydrocodone is not recommended for patients taking monoamine oxidase inhibitors (MAOIs) or within 14 days of MAOI discontinuation. If coadministration is required, use test doses and frequent titration of small benzhydrocodone. Risk D: Consider Therapy Modification

Benztropine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Benztropine. Risk C: Monitor

Beta2-Agonists: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Beta2-Agonists. Risk C: Monitor

Betahistine: Monoamine Oxidase Inhibitors may increase serum concentration of Betahistine. Risk C: Monitor

Bezafibrate: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Bezafibrate. Risk X: Avoid

Biperiden: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Biperiden. Risk C: Monitor

Blonanserin: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Blonanserin. Specifically, the risk of seizures may be increased. Risk C: Monitor

Bornaprine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Bornaprine. Risk C: Monitor

Bornaprine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Botulinum Toxin-Containing Products: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Brexpiprazole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Brexpiprazole. Specifically, the risk of seizures may be increased. Risk C: Monitor

Brimonidine (Ophthalmic): Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Brimonidine (Ophthalmic). Monoamine Oxidase Inhibitors may increase serum concentration of Brimonidine (Ophthalmic). Risk C: Monitor

Brimonidine (Topical): Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Brimonidine (Topical). Monoamine Oxidase Inhibitors may increase serum concentration of Brimonidine (Topical). Risk C: Monitor

Bromperidol: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Bromperidol. Risk C: Monitor

Bromperidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Bromperidol. Specifically, the risk of seizures may be increased. Risk C: Monitor

Buclizine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Buclizine. Risk C: Monitor

Buprenorphine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

BuPROPion: Monoamine Oxidase Inhibitors may increase hypertensive effects of BuPROPion. Risk X: Avoid

BusPIRone: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Butorphanol: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Cannabinoid-Containing Products: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of Cannabinoid-Containing Products. Risk C: Monitor

CarBAMazepine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Management: Do not use carbamazepine during, or within 14 days of discontinuing, treatment with a monoamine oxidase inhibitor. Risk X: Avoid

Carbinoxamine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Carbinoxamine. Specifically, the anticholinergic effects of carbinoxamine may be enhanced and prolonged. Risk X: Avoid

Carbonic Anhydrase Inhibitors: May decrease therapeutic effects of Methenamine. Management: Consider avoiding the concomitant use of medications that alkalinize the urine, such as carbonic anhydrase inhibitors, and methenamine. Monitor for decreased therapeutic effects of methenamine if used concomitant with a carbonic anhydrase inhibitor. Risk D: Consider Therapy Modification

Cariprazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Cariprazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Cerebrolysin: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Chlorphenesin Carbamate: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

ChlorproMAZINE: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of ChlorproMAZINE. Specifically, the risk of seizures may be increased. Risk C: Monitor

ChlorproPAMIDE: Urinary Acidifying Agents may increase serum concentration of ChlorproPAMIDE. Risk C: Monitor

Chlorprothixene: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Chlorprothixene. Risk C: Monitor

Cholera Vaccine: Antibiotics may decrease therapeutic effects of Cholera Vaccine. Management: Avoid cholera vaccine in patients receiving systemic antibiotics, and within 14 days following the use of oral or parenteral antibiotics. Risk X: Avoid

Cimetropium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Cimetropium. Risk X: Avoid

Clemastine: Monoamine Oxidase Inhibitors may increase anticholinergic effects of Clemastine. Risk C: Monitor

Clothiapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Clothiapine. Specifically, the risk of seizures may be increased. Risk C: Monitor

CloZAPine: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of CloZAPine. Management: Consider alternatives to this combination whenever possible. If combined, monitor closely for signs and symptoms of gastrointestinal hypomotility and consider prophylactic laxative treatment. Risk D: Consider Therapy Modification

Cocaine (Topical): May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Codeine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Codeine. Risk X: Avoid

COMT Inhibitors: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Management: Avoid coadministration of COMT inhibitors and nonselective monoamine oxidase inhibitors (MAOIs) (eg, isocarboxazid, phenelzine, tranylcypromine, linezolid, methylene blue) whenever possible. Risk D: Consider Therapy Modification

Cyclizine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Cyclobenzaprine: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Cyproheptadine: May decrease serotonergic effects of Monoamine Oxidase Inhibitors. Monoamine Oxidase Inhibitors may increase anticholinergic effects of Cyproheptadine. Risk X: Avoid

Dapoxetine: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Do not use serotonergic agents (high risk) with dapoxetine or within 7 days of serotonergic agent discontinuation. Do not use dapoxetine within 14 days of monoamine oxidase inhibitor use. Dapoxetine labeling lists this combination as contraindicated. Risk X: Avoid

Darifenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Darifenacin. Risk C: Monitor

Deutetrabenazine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Deutetrabenazine. Risk X: Avoid

Dexmethylphenidate: Monoamine Oxidase Inhibitors may increase hypertensive effects of Dexmethylphenidate. Risk X: Avoid

Dextromethorphan: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This may cause serotonin syndrome. Risk X: Avoid

Diamorphine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Diamorphine. Risk X: Avoid

Dicyclomine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dicyclomine. Risk C: Monitor

Diethylpropion: Monoamine Oxidase Inhibitors may increase hypertensive effects of Diethylpropion. Risk X: Avoid

Difenoxin: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Dihydrocodeine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Management: Consider avoiding use of dihydrocodeine while the patient is taking monoamine oxidase inhibitors (MAOIs) and for 2 weeks after MAOI discontinuation. Risk D: Consider Therapy Modification

Dimethindene (Systemic): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dimethindene (Systemic). Risk C: Monitor

Diphenoxylate: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Domperidone: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Domperidone. Monoamine Oxidase Inhibitors may decrease therapeutic effects of Domperidone. Domperidone may decrease therapeutic effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

DOPamine: Monoamine Oxidase Inhibitors may increase hypertensive effects of DOPamine. Management: Initiate dopamine at no greater than one-tenth (1/10) of the usual dose in patients who are taking (or have taken within the last 2 to 3 weeks) monoamine oxidase inhibitors. Monitor for an exaggerated hypertensive response to dopamine. Risk D: Consider Therapy Modification

Doxapram: Monoamine Oxidase Inhibitors may increase hypertensive effects of Doxapram. Risk C: Monitor

Doxylamine: Monoamine Oxidase Inhibitors may increase anticholinergic effects of Doxylamine. Risk X: Avoid

DroNABinol: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of DroNABinol. Risk X: Avoid

DroPERidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of DroPERidol. Specifically, the risk of seizures may be increased. Risk C: Monitor

Droxidopa: Monoamine Oxidase Inhibitors may increase hypertensive effects of Droxidopa. Risk X: Avoid

Eluxadoline: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of Eluxadoline. Risk X: Avoid

EPINEPHrine (Oral Inhalation): Monoamine Oxidase Inhibitors may increase hypertensive effects of EPINEPHrine (Oral Inhalation). Risk X: Avoid

Ergot Derivatives: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Esketamine (Nasal): May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk C: Monitor

Fecal Microbiota (Live) (Oral): May decrease therapeutic effects of Antibiotics. Risk X: Avoid

Fecal Microbiota (Live) (Rectal): Antibiotics may decrease therapeutic effects of Fecal Microbiota (Live) (Rectal). Risk X: Avoid

Fenfluramine: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

FentaNYL: Methylene Blue may increase serotonergic effects of FentaNYL. This could result in serotonin syndrome. Risk X: Avoid

Fesoterodine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Fesoterodine. Risk C: Monitor

Flupentixol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Flupentixol. Specifically, the risk of seizures may be increased. Risk C: Monitor

FluPHENAZine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of FluPHENAZine. Specifically, the risk of seizures may be increased. Risk C: Monitor

FluPHENAZine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Gastrointestinal Agents (Prokinetic): Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Gastrointestinal Agents (Prokinetic). Risk C: Monitor

Gepirone: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Gepotidacin: May decrease anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Glucagon: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Risk C: Monitor

Glycopyrrolate (Oral Inhalation): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Glycopyrrolate (Oral Inhalation). Risk X: Avoid

Glycopyrrolate (Systemic): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Glycopyrrolate (Systemic). Risk C: Monitor

Glycopyrronium (Topical): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid

Guanethidine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Haloperidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Haloperidol. Specifically, the risk of seizures may be increased. Risk C: Monitor

HYDROcodone: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Monoamine Oxidase Inhibitors may increase adverse/toxic effects of HYDROcodone. Management: Consider alternatives to this combination when possible. If coadministration is required, use test doses, titrate small doses frequently, and monitor patients closely for evidence of serotonergic and opioid toxicities. Risk D: Consider Therapy Modification

HYDROmorphone: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of HYDROmorphone. Management: Coadministration of hydromorphone and monoamine oxidase (MAO) inhibitors (or within 14 days of stopping an MAO inhibitor) is not recommended. If required, use test doses, titrate small doses frequently, and monitor for CNS and respitatory depression. Risk D: Consider Therapy Modification

Iloperidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iloperidone. Specifically, the risk of seizures may be increased. Risk C: Monitor

Immune Checkpoint Inhibitors (Anti-PD-1, -PD-L1, and -CTLA4 Therapies): Antibiotics may decrease therapeutic effects of Immune Checkpoint Inhibitors (Anti-PD-1, -PD-L1, and -CTLA4 Therapies). Risk C: Monitor

Indoramin: Monoamine Oxidase Inhibitors may increase hypotensive effects of Indoramin. Risk X: Avoid

Iobenguane Radiopharmaceutical Products: Monoamine Oxidase Inhibitors may decrease therapeutic effects of Iobenguane Radiopharmaceutical Products. Management: Discontinue all drugs that may inhibit or interfere with catecholamine transport or uptake for at least 5 biological half-lives before iobenguane administration. Do not administer these drugs until at least 7 days after each iobenguane dose. Risk X: Avoid

Iohexol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iohexol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iohexol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification

Iomeprol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iomeprol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iomeprol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification

Iopamidol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Iopamidol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iopamidol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic antiseizure drugs. Risk D: Consider Therapy Modification

Ipratropium (Nasal): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Ipratropium (Oral Inhalation): May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid

Isoproterenol: Monoamine Oxidase Inhibitors may increase therapeutic effects of Isoproterenol. Risk C: Monitor

Itopride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Itopride. Risk C: Monitor

Ketoconazole (Systemic): Hyoscyamine may decrease serum concentration of Ketoconazole (Systemic). Management: Take hyoscyamine at least 2 hours after ingestion of ketoconazole. Monitor for decreased therapeutic effects of ketoconazole if used together with hyoscyamine. Risk D: Consider Therapy Modification

Lactobacillus and Estriol: Antibiotics may decrease therapeutic effects of Lactobacillus and Estriol. Risk C: Monitor

Lasmiditan: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Levodopa-Foslevodopa: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Of particular concern is the development of hypertensive reactions when levodopa is used with nonselective MAOI. Risk X: Avoid

Levomethadone: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Levonordefrin: Monoamine Oxidase Inhibitors may increase hypertensive effects of Levonordefrin. Management: Avoid the use of levonordefrin during or within 2 weeks of treatment with a monoamine oxidase inhibitor whenever possible. If levonordefrin cannot be avoided during this period, monitor closely for enhanced or prolonged increases in blood pressure. Risk D: Consider Therapy Modification

Levosulpiride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Levosulpiride. Risk X: Avoid

Linezolid: Methylene Blue may increase serotonergic effects of Linezolid. This could result in serotonin syndrome. Risk X: Avoid

Lithium: Methylene Blue may increase serotonergic effects of Lithium. This could result in serotonin syndrome. Management: Consider alternatives to this drug combination. If combined, monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes). Risk D: Consider Therapy Modification

Loxapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Loxapine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Lumateperone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Lumateperone. Specifically, the risk of seizures may be increased. Risk C: Monitor

Lurasidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Lurasidone. Specifically, the risk of seizures may be increased. Risk C: Monitor

Maprotiline: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Mecamylamine: Urinary Acidifying Agents may decrease serum concentration of Mecamylamine. Risk C: Monitor

Melperone: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Meptazinol: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Meptazinol. Risk X: Avoid

Mequitazine: Monoamine Oxidase Inhibitors may increase anticholinergic effects of Mequitazine. Risk X: Avoid

Metaraminol: Monoamine Oxidase Inhibitors may increase hypertensive effects of Metaraminol. Risk C: Monitor

Metaxalone: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Methadone: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Methotrimeprazine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Methotrimeprazine. Specifically, monoamine oxidase inhibitors may enhance dopamine blockade, possible increasing the risk for neuroleptic malignant syndrome. Methotrimeprazine may increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Methoxsalen (Systemic): Methylene Blue may increase photosensitizing effects of Methoxsalen (Systemic). Risk C: Monitor

Methscopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Methscopolamine. Risk C: Monitor

Methyldopa: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Methyldopa. Risk X: Avoid

Methylphenidate: Monoamine Oxidase Inhibitors may increase hypertensive effects of Methylphenidate. Risk X: Avoid

Metoclopramide: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Mianserin: Monoamine Oxidase Inhibitors may increase neurotoxic effects of Mianserin. Risk X: Avoid

Mirabegron: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Mirabegron. Risk C: Monitor

Mivacurium: Monoamine Oxidase Inhibitors may increase serum concentration of Mivacurium. Risk C: Monitor

Molindone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Molindone. Specifically, the risk of seizures may be increased. Risk C: Monitor

Monoamine Oxidase Inhibitors (Antidepressant): May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Monoamine Oxidase Inhibitors (Type B): May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Morphine (Systemic): Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Morphine (Systemic). Risk X: Avoid

Mycophenolate: Antibiotics may decrease active metabolite exposure of Mycophenolate. Specifically, concentrations of mycophenolic acid (MPA) may be reduced. Risk C: Monitor

Nalbuphine: Monoamine Oxidase Inhibitors may increase CNS depressant effects of Nalbuphine. Nalbuphine may increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Nalbuphine may increase hypertensive effects of Monoamine Oxidase Inhibitors. Management: Use of nalbuphine is not recommended in patients taking MAOIs, or within 14 days of stopping MAOI therapy. If urgent nalbuphine use is needed, use test doses and frequent titration while monitoring blood pressure, CNS depression, and serotonergic toxicity Risk D: Consider Therapy Modification

Nefazodone: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Nefopam: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Nefopam. Risk X: Avoid

Nitroglycerin: Agents with Clinically Relevant Anticholinergic Effects may decrease absorption of Nitroglycerin. Specifically, anticholinergic agents may decrease the dissolution of sublingual nitroglycerin tablets, possibly impairing or slowing nitroglycerin absorption. Risk C: Monitor

Normethadone: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Normethadone. Risk X: Avoid

OLANZapine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OLANZapine. Risk C: Monitor

OLANZapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of OLANZapine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Ondansetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Opicapone: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Opioid Agonists: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Opioid Agonists. Specifically, the risk for constipation and urinary retention may be increased with this combination. Risk C: Monitor

Opioid Agonists: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Opipramol: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Opium: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Opium. Risk X: Avoid

Oxatomide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid

Oxitriptan: Serotonergic Agents (High Risk) may increase serotonergic effects of Oxitriptan. This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

OxyBUTYnin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OxyBUTYnin. Risk C: Monitor

OxyCODONE: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Management: Use of oxycodone is not recommended for patients taking MAOIs or within 14 days of MAOI discontinuation. If combined, use test doses and frequent titration of small doses while monitoring blood pressure, CNS depression, and signs of serotonin syndrome. Risk D: Consider Therapy Modification

OxyMORphone: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Ozanimod: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Paliperidone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Paliperidone. Specifically, the risk of seizures may be increased. Risk C: Monitor

Pegulicianine: Coadministration of Methylene Blue and Pegulicianine may alter diagnostic results. Risk X: Avoid

Perazine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Periciazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Periciazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Perphenazine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Perphenazine. Risk C: Monitor

Perphenazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Perphenazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Pheniramine: May increase anticholinergic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Pholcodine: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Pimozide: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Pimozide. Specifically, the risk of seizures may be increased. Risk C: Monitor

Pipamperone: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Pipamperone. Specifically, the risk of seizures may be increased. Risk X: Avoid

Pizotifen: Monoamine Oxidase Inhibitors may increase anticholinergic effects of Pizotifen. Risk X: Avoid

Polyethylene Glycol-Electrolyte Solution: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Polyethylene Glycol-Electrolyte Solution. Specifically, the risk of seizure may be increased. Risk C: Monitor

Potassium Chloride: Agents with Clinically Relevant Anticholinergic Effects may increase ulcerogenic effects of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Risk X: Avoid

Potassium Citrate: Agents with Clinically Relevant Anticholinergic Effects may increase ulcerogenic effects of Potassium Citrate. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium citrate. Risk X: Avoid

Pramlintide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. These effects are specific to the GI tract. Risk X: Avoid

Prochlorperazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Prochlorperazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Promazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Promazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Promethazine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Promethazine. Risk C: Monitor

Propantheline: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Propantheline. Risk C: Monitor

Propiverine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

QUEtiapine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of QUEtiapine. Specifically, the risk of seizures may be increased. Risk C: Monitor

QuiNIDine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor

Ramosetron: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of Ramosetron. Risk C: Monitor

Ramosetron: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Reboxetine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Reboxetine. Risk X: Avoid

Remifentanil: May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Remifentanil. Specifically, the risk for opioid toxicity (eg, respiratory depression) may be increased. Management: The use of remifentanil is not recommended for patients taking monoamine oxidase inhibitors (MAOIs) or within 14 days of MAOI discontinuation. If coadministration is required, use test doses and titrate small doses of remifentanil frequently. Risk D: Consider Therapy Modification

Reserpine: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Reserpine. Existing MAOI therapy can result in paradoxical effects of added reserpine (e.g., excitation, hypertension). Management: Monoamine oxidase inhibitors (MAOIs) should be avoided or used with great caution in patients who are also receiving reserpine. Monitor closely for paradoxical effects of reserpine (eg, excitation, hypertension). Risk D: Consider Therapy Modification

Revefenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Revefenacin. Risk X: Avoid

RisperiDONE: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of RisperiDONE. Specifically, the risk of seizures may be increased. Risk C: Monitor

Rivastigmine: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Rivastigmine. Rivastigmine may decrease therapeutic effects of Agents with Clinically Relevant Anticholinergic Effects. Management: Use of rivastigmine with an anticholinergic agent is not recommended unless clinically necessary. If the combination is necessary, monitor for reduced anticholinergic effects. Risk D: Consider Therapy Modification

Scopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Scopolamine. Risk C: Monitor

Secretin: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Secretin. Management: Avoid concomitant use of anticholinergic agents and secretin. Discontinue anticholinergic agents at least 5 half-lives prior to administration of secretin. Risk D: Consider Therapy Modification

Selective Serotonin Reuptake Inhibitor: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Serotonergic Non-Opioid CNS Depressants: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Serotonergic Opioids (High Risk): Methylene Blue may increase serotonergic effects of Serotonergic Opioids (High Risk). This could result in serotonin syndrome. Risk X: Avoid

Serotonin 5-HT1D Receptor Agonists (Triptans): May increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Monoamine Oxidase Inhibitors may increase serum concentration of Serotonin 5-HT1D Receptor Agonists (Triptans). Risk X: Avoid

Serotonin/Norepinephrine Reuptake Inhibitor: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Sertindole: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sertindole. Specifically, the risk of seizures may be increased. Risk C: Monitor

Sevoflurane: Monoamine Oxidase Inhibitors may increase adverse/toxic effects of Sevoflurane. Specifically, the risk of hemodynamic instability may be increased. Risk C: Monitor

Sodium Phosphates: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sodium Phosphates. Specifically, the risk of seizure or loss of consciousness may be increased in patients with significant sodium phosphate-induced fluid or electrolyte abnormalities. Risk C: Monitor

Sodium Picosulfate: Antibiotics may decrease therapeutic effects of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Risk D: Consider Therapy Modification

Sofpironium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Sofpironium. Risk X: Avoid

Solriamfetol: Monoamine Oxidase Inhibitors may increase hypertensive effects of Solriamfetol. Risk X: Avoid

St John's Wort: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. St John's Wort may decrease serum concentration of Serotonergic Agents (High Risk). Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

SUFentanil: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Specifically, the risk for serotonin syndrome or opioid toxicities (eg, respiratory depression, coma) may be increased. Management: Sufentanil should not be used with monoamine oxidase (MAO) inhibitors (or within 14 days of stopping an MAO inhibitor) due to the potential for serotonin syndrome and/or excessive CNS depression. Risk X: Avoid

SulfaSALAzine: Methenamine may increase adverse/toxic effects of SulfaSALAzine. Specifically, the combination may result in the formation of an insoluble precipitate in the urine. Risk X: Avoid

Sulfonamide Antibiotics: Methenamine may increase adverse/toxic effects of Sulfonamide Antibiotics. Specifically, the combination may result in the formation of an insoluble precipitate in the urine. Risk X: Avoid

Sulpiride: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Sulpiride. Specifically, the risk of seizures may be increased. Risk C: Monitor

Syrian Rue: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Tapentadol: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Specifically, the additive effects of norepinephrine may lead to adverse cardiovascular effects. Tapentadol may increase serotonergic effects of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Risk X: Avoid

Tetrabenazine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Thiazide and Thiazide-Like Diuretics: May decrease therapeutic effects of Methenamine. Risk C: Monitor

Thioridazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Thioridazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Thiothixene: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Thiothixene. Risk C: Monitor

Thiothixene: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Thiothixene. Specifically, the risk of seizures may be increased. Risk C: Monitor

Tianeptine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Tiapride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Tiapride. Risk C: Monitor

Tilidine: May increase serotonergic effects of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Risk C: Monitor

Tiotropium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Tiotropium. Risk X: Avoid

Tolterodine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Tolterodine. Risk C: Monitor

Tricyclic Antidepressants: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Trifluoperazine: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Trifluoperazine. Specifically, the risk of seizures may be increased. Risk C: Monitor

Trimethobenzamide: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Trimethobenzamide. Risk C: Monitor

Trospium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Trospium. Risk C: Monitor

Tryptophan: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Typhoid Vaccine: Antibiotics may decrease therapeutic effects of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Avoid use of live attenuated typhoid vaccine (Ty21a) in patients being treated with systemic antibacterial agents. Postpone vaccination until 3 days after cessation of antibiotics and avoid starting antibiotics within 3 days of last vaccine dose. Risk D: Consider Therapy Modification

Tyrosine: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Umeclidinium: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid

Uva Ursi: Urinary Acidifying Agents may decrease therapeutic effects of Uva Ursi. Management: Consider avoiding use of uva ursi with agents that acidify the urine, as this may impair uva ursi efficacy. Risk D: Consider Therapy Modification

Valbenazine: May increase adverse/toxic effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Viloxazine: May increase hypertensive effects of Monoamine Oxidase Inhibitors. Risk X: Avoid

Ziprasidone: May increase serotonergic effects of Methylene Blue. This could result in serotonin syndrome. Risk X: Avoid

Zuclopenthixol: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Zuclopenthixol. Risk C: Monitor

Zuclopenthixol: Agents With Seizure Threshold Lowering Potential may increase adverse/toxic effects of Zuclopenthixol. Specifically, the risk of seizures may be increased. Risk C: Monitor