Note: Dextromethorphan dosing in terms of dextromethorphan hydrobromide; pyrilamine dosing in terms of pyrilamine maleate.
Allergies/common cold/hay fever: Oral:
Liquid: Dextromethorphan 7.5 mg/pyrilamine 7.5 mg per 5 mL: 20 mL every 6 to 8 hours; maximum: 80 mL/24 hours.
Tablet: Dextromethorphan 30 mg/pyrilamine 30 mg per tablet: 1 tablet every 6 to 8 hours; maximum: 4 tablets/24 hours.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in manufacturer's labeling.
There are no dosage adjustments provided in manufacturer's labeling.
Avoid use (Ref).
(For additional information see "Dextromethorphan and pyrilamine: Pediatric drug information")
Cough and upper respiratory allergy symptoms: Oral:
Dextromethorphan 7.5 mg/pyrilamine 7.5 mg per 5 mL:
Children 6 to <12 years: 10 mL every 6 to 8 hours as needed. Maximum dose: 40 mL/24 hours.
Children ≥12 years and Adolescents: 20 mL every 6 to 8 hours as needed. Maximum dose: 80 mL/24 hours.
Dextromethorphan 30 mg/pyrilamine 30 mg per tablet:
Children ≥12 years and Adolescents: 1 tablet every 6 to 8 hours as needed. Maximum dose: 4 tablets/24 hours.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer's labeling.
There are no dosage adjustments provided in the manufacturer's labeling.
See Dextromethorphan monograph.
OTC labeling: When used for self-medication, do not use with or within 14 days of monoamine oxidase inhibitors or for persistent or chronic cough such as occurs with smoking, asthma, or emphysema, or if cough is accompanied by excessive phlegm (mucus), unless directed by health care provider.
Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
Concerns related to adverse effects:
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks that require mental alertness (eg, operating machinery, driving).
Disease-related concerns:
• Cardiovascular disease: Use with caution in patients with cardiovascular disease.
• Diabetes: Use with caution in patients with diabetes mellitus.
• Increased intraocular pressure/glaucoma: Use with caution in patients with increased intraocular pressure or glaucoma.
• Prostatic hyperplasia/urinary obstruction: Use with caution in patients with prostatic hyperplasia and/or urinary obstruction.
• Respiratory disease: Use caution in patients with breathing problems such as chronic bronchitis or emphysema.
• Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.
Concurrent drug therapy issues:
• Sedatives: Effects may be potentiated when used with other sedative drugs or ethanol.
Special populations:
• CYP2D6 poor metabolizers: Dextromethorphan is metabolized by hepatic CYP2D6. Poor metabolizers of CYP2D6 may have exaggerated or prolonged effects of dextromethorphan. Increased risk may be seen with concomitant use of potent CYP2D6 inhibitors; use with caution (Abduljalil 2010; Jurica 2012; Sager 2014; Zhou 2009).
• Debilitated patients: Use with caution in patients who are sedated, debilitated, or confined to a supine position.
• Pediatric: Antihistamines may cause excitation in young children. Do not exceed pediatric dosing recommendations. If no recommendations exist on OTC labeling for patient’s age, the product should not be administered without the guidance of a physician. Not for OTC use in children <6 years of age.
Dosage form specific issues:
• Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated with hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP 1997; Zar 2007).
Other warnings/precautions:
• Self-medication (OTC use): When used for self-medication (OTC), notify health care provider if symptoms do not improve within 7 days, or are accompanied by fever, rash, or persistent headache.
Safety and efficacy for the use of cough and cold products in pediatric patients <4 years of age is limited; the AAP warns against the use of these products for respiratory illnesses in young children. Serious adverse effects including death have been reported (in some cases, high blood concentrations of pseudoephedrine were found). Many of these products contain multiple active ingredients, increasing the risk of accidental overdose when used with other products. The FDA does not recommend OTC uses for these products in pediatric patients <2 years of age and recommends to use with caution in pediatric patients ≥2 years of age. Health care providers are reminded to ask caregivers about the use of OTC cough and cold products in order to avoid exposure to multiple medications containing the same ingredient (AAP 2018; CDC 2007; FDA 2017; FDA 2018).
Some dosage forms may contain propylene glycol; in neonates large amounts of propylene glycol delivered orally, intravenously (eg, >3,000 mg/day), or topically have been associated with potentially fatal toxicities which can include metabolic acidosis, seizures, renal failure, and CNS depression; toxicities have also been reported in children and adults including hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP 1997; Shehab 2009).
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Liquid, Oral:
CapHist DM: Dextromethorphan hydrobromide 7.5 mg and pyrilamine maleate 7.5 mg per 5 mL (473 mL) [alcohol free, dye free, gluten free, sugar free; contains methylparaben, propylene glycol, propylparaben; candy apple flavor]
Capron DM: Dextromethorphan hydrobromide 7.5 mg and pyrilamine maleate 7.5 mg per 5 mL (473 mL) [alcohol free, dye free, gluten free, sugar free; contains methylparaben, propylene glycol, propylparaben; candy apple flavor]
CuraHIST DM: Dextromethorphan hydrobromide 7.5 mg and pyrilamine maleate 7.5 mg per 5 mL (473 mL) [alcohol free, dye free, gluten free, sugar free; contains methylparaben, propylene glycol, propylparaben; apple pie flavor]
Generic: Dextromethorphan hydrobromide 7.5 mg and pyrilamine maleate 7.5 mg per 5 mL (473 mL)
Tablet, Oral:
Capron DMT: Dextromethorphan hydrobromide 30 mg and pyrilamine maleate 30 mg
Yes
Liquid (Dextromethorphan-Pyrilamine Oral)
7.5-7.5 mg/5 mL (per mL): $0.07
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
Oral: Administer liquid formulation with an accurate measuring device; do not use a household teaspoon (overdosage may occur).
Oral: Administer liquid products with an accurate measuring device; do not use a household teaspoon (overdosage may occur).
Allergies/common cold/hay fever: Temporarily relieves symptoms due to the common cold, hay fever (allergic rhinitis), or other upper respiratory allergies.
Beers Criteria: Pyrilamine, a first-generation antihistamine, is identified in the Beers Criteria as a potentially inappropriate medication to be avoided in patients ≥65 years of age (independent of diagnosis or condition) due to its potent anticholinergic properties resulting in increased risk of confusion, dry mouth, constipation, and other anticholinergic effects or toxicity; use should also be avoided due to reduced clearance with advanced age and tolerance associated with use as a hypnotic. Exposure to concurrent anticholinergic drugs also increases risk of falls, delirium, and dementia; consider total anticholinergic burden when conducting medication reviews (Beers Criteria [AGS 2023]).
The Institute for Safe Medication Practices (ISMP) includes this medication among its list of drugs (pediatric liquid medications requiring measurement) which have a heightened risk of causing significant patient harm when used in error (High-Alert Medications in Community/Ambulatory Care Settings).
Refer to individual components.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
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
Acrivastine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Ajmaline: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Alcohol (Ethyl): CNS Depressants may increase CNS depressant effects of Alcohol (Ethyl). Risk C: Monitor
Alizapride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Amantadine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Amezinium: Antihistamines may increase stimulatory effects of Amezinium. Risk C: Monitor
Amisulpride (Oral): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Artemether and Lumefantrine: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Articaine: May increase CNS depressant effects of CNS Depressants. Management: Consider reducing the dose of articaine if possible when used in patients who are also receiving CNS depressants. Monitor for excessive CNS depressant effects with any combined use. Risk D: Consider Therapy Modification
Azelastine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Benperidol: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Benperidol. Risk C: Monitor
Benperidol: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Benztropine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Benztropine. Risk C: Monitor
Benzylpenicilloyl Polylysine: Coadministration of Antihistamines and Benzylpenicilloyl Polylysine may alter diagnostic results. Management: Suspend systemic H1 antagonists for benzylpenicilloyl-polylysine skin testing and delay testing until systemic antihistaminic effects have dissipated. A histamine skin test may be used to assess persistent antihistaminic effects. Risk D: Consider Therapy Modification
Betahistine: Antihistamines may decrease therapeutic effects of Betahistine. Betahistine may decrease therapeutic effects of Antihistamines. Risk C: Monitor
Biperiden: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Biperiden. Risk C: Monitor
Blonanserin: CNS Depressants may increase CNS depressant effects of Blonanserin. Management: Use caution if coadministering blonanserin and CNS depressants; dose reduction of the other CNS depressant may be required. Strong CNS depressants should not be coadministered with blonanserin. Risk D: Consider Therapy Modification
Bornaprine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Bornaprine. Risk C: Monitor
Botulinum Toxin-Containing Products: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Brexanolone: CNS Depressants may increase CNS depressant effects of Brexanolone. Risk C: Monitor
Brimonidine (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Bromopride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Bromperidol: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Buclizine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Buclizine. Risk C: Monitor
Buclizine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Buprenorphine: CNS Depressants may increase CNS depressant effects of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine at lower doses in patients already receiving CNS depressants. Risk D: Consider Therapy Modification
BusPIRone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Cannabinoid-Containing Products: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of Cannabinoid-Containing Products. Risk C: Monitor
Cannabinoid-Containing Products: CNS Depressants may increase CNS depressant effects of Cannabinoid-Containing Products. Risk C: Monitor
Certoparin: Antihistamines may increase therapeutic effects of Certoparin. Risk C: Monitor
Cetirizine (Systemic): May increase CNS depressant effects of CNS Depressants. Management: Consider avoiding this combination if possible. If required, monitor for excessive sedation or CNS depression, limit the dose and duration of combination therapy, and consider CNS depressant dose reductions. Risk D: Consider Therapy Modification
Chloral Hydrate/Chloral Betaine: CNS Depressants may increase CNS depressant effects of Chloral Hydrate/Chloral Betaine. Management: Consider alternatives to the use of chloral hydrate or chloral betaine and additional CNS depressants. If combined, consider a dose reduction of either agent and monitor closely for enhanced CNS depressive effects. Risk D: Consider Therapy Modification
Chlormethiazole: May increase CNS depressant effects of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Risk D: Consider Therapy Modification
Chlorphenesin Carbamate: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
Chlorprothixene: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Chlorprothixene. Risk C: Monitor
Cimetropium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Cimetropium. Risk X: Avoid
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
CNS Depressants: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
Cyclizine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
CYP2D6 Inhibitors (Moderate): May increase serum concentration of Dextromethorphan. Risk C: Monitor
CYP2D6 Inhibitors (Strong): May increase serum concentration of Dextromethorphan. Risk C: Monitor
Dantrolene: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Daridorexant: May increase CNS depressant effects of CNS Depressants. Management: Dose reduction of daridorexant and/or any other CNS depressant may be necessary. Use of daridorexant with alcohol is not recommended, and the use of daridorexant with any other drug to treat insomnia is not recommended. Risk D: Consider Therapy Modification
Darifenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Darifenacin. Risk C: Monitor
DexmedeTOMIDine: CNS Depressants may increase CNS depressant effects of DexmedeTOMIDine. Management: Monitor for increased CNS depression during coadministration of dexmedetomidine and CNS depressants, and consider dose reductions of either agent to avoid excessive CNS depression. Risk D: Consider Therapy Modification
Dicyclomine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dicyclomine. Risk C: Monitor
Difelikefalin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Difenoxin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Dihydralazine: CNS Depressants may increase hypotensive effects of Dihydralazine. Risk C: Monitor
Dimethindene (Systemic): Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Dimethindene (Systemic). Risk C: Monitor
Dimethindene (Topical): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Disulfiram: May increase adverse/toxic effects of Products Containing Ethanol. Management: Do not use disulfiram with dosage forms that contain ethanol. Risk X: Avoid
Dothiepin: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Doxylamine: CNS Depressants may increase CNS depressant effects of Doxylamine. Risk C: Monitor
DroNABinol: Agents with Clinically Relevant Anticholinergic Effects may increase tachycardic effects of DroNABinol. Risk X: Avoid
DroPERidol: May increase CNS depressant effects of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Risk D: Consider Therapy Modification
Eluxadoline: Agents with Clinically Relevant Anticholinergic Effects may increase constipating effects of Eluxadoline. Risk X: Avoid
Emedastine (Systemic): May increase CNS depressant effects of CNS Depressants. Management: Consider avoiding this combination if possible. If required, monitor for excessive sedation or CNS depression, limit the dose and duration of combination therapy, and consider CNS depressant dose reductions. Risk C: Monitor
Entacapone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Esketamine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Fesoterodine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Fesoterodine. Risk C: Monitor
Flunarizine: CNS Depressants may increase CNS depressant effects of Flunarizine. Risk X: Avoid
Flunitrazepam: CNS Depressants may increase CNS depressant effects of Flunitrazepam. Management: Reduce the dose of CNS depressants when combined with flunitrazepam and monitor patients for evidence of CNS depression (eg, sedation, respiratory depression). Use non-CNS depressant alternatives when available. Risk D: Consider Therapy Modification
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
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
Hyaluronidase: Antihistamines may decrease therapeutic effects of Hyaluronidase. Risk C: Monitor
HydrOXYzine: May increase CNS depressant effects of CNS Depressants. Management: Consider a decrease in the CNS depressant dose, as appropriate, when used together with hydroxyzine. Increase monitoring of signs/symptoms of CNS depression in any patient receiving hydroxyzine together with another CNS depressant. 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
Itopride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Itopride. Risk C: Monitor
Ixabepilone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Kava Kava: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Ketotifen (Systemic): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Kratom: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Lemborexant: May increase CNS depressant effects of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Risk D: Consider Therapy Modification
Levocetirizine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Levosulpiride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Levosulpiride. Risk X: Avoid
Lisuride: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Lofepramine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Lofexidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Loxapine: CNS Depressants may increase CNS depressant effects of Loxapine. Management: Consider reducing the dose of CNS depressants administered concomitantly with loxapine due to an increased risk of respiratory depression, sedation, hypotension, and syncope. Risk D: Consider Therapy Modification
Magnesium Sulfate: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Maprotiline: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Maprotiline. Risk C: Monitor
Mavorixafor: May increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk X: Avoid
Melitracen [INT]: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Melperone: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Memantine: NMDA Receptor Antagonists may increase adverse/toxic effects of Memantine. Risk C: Monitor
Mequitazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Metergoline: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Methotrimeprazine: May increase CNS depressant effects of Products Containing Ethanol. Management: Avoid products containing alcohol in patients treated with methotrimeprazine. Risk X: Avoid
Methoxyflurane: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Methscopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Methscopolamine. Risk C: Monitor
Metoclopramide: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
MetroNIDAZOLE (Systemic): May increase adverse/toxic effects of Products Containing Ethanol. A disulfiram-like reaction may occur. Risk X: Avoid
MetroNIDAZOLE (Topical): May increase adverse/toxic effects of Products Containing Ethanol. A disulfiram-like reaction may occur. Risk C: Monitor
MetyroSINE: CNS Depressants may increase sedative effects of MetyroSINE. Risk C: Monitor
Minocycline (Systemic): May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Mirabegron: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Mirabegron. Risk C: Monitor
Monoamine Oxidase Inhibitors: Dextromethorphan may increase serotonergic effects of Monoamine Oxidase Inhibitors. This may cause serotonin syndrome. Risk X: Avoid
Moxonidine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Nabilone: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Nalfurafine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
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
Noscapine: CNS Depressants may increase adverse/toxic effects of Noscapine. Risk X: Avoid
OLANZapine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OLANZapine. Risk C: Monitor
Olopatadine (Nasal): May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Opicapone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Opioid Agonists: CNS Depressants may increase CNS depressant effects of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider Therapy Modification
Opipramol: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Opipramol: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Orphenadrine: CNS Depressants may increase CNS depressant effects of Orphenadrine. Risk X: Avoid
Oxatomide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Oxomemazine: May increase CNS depressant effects of CNS Depressants. Risk X: Avoid
Oxybate Salt Products: CNS Depressants may increase CNS depressant effects of Oxybate Salt Products. Management: Consider alternatives to this combination when possible. If combined, dose reduction or discontinuation of one or more CNS depressants (including the oxybate salt product) should be considered. Interrupt oxybate salt treatment during short-term opioid use Risk D: Consider Therapy Modification
OxyBUTYnin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of OxyBUTYnin. Risk C: Monitor
OxyCODONE: CNS Depressants may increase CNS depressant effects of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Risk D: Consider Therapy Modification
Paliperidone: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Paraldehyde: CNS Depressants may increase CNS depressant effects of Paraldehyde. Risk X: Avoid
Parecoxib: May increase serum concentration of Dextromethorphan. Risk C: Monitor
Peginterferon Alfa-2b: May decrease serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Peginterferon Alfa-2b may increase serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Risk C: Monitor
Perampanel: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Perazine: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk C: Monitor
Periciazine: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Perphenazine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Perphenazine. Risk C: Monitor
Pipamperone: May increase adverse/toxic effects of CNS Depressants. Risk C: Monitor
Piribedil: CNS Depressants may increase CNS depressant effects of Piribedil. Risk C: Monitor
Pitolisant: Antihistamines may decrease therapeutic effects of Pitolisant. Risk X: Avoid
Pizotifen: May increase CNS depressant effects of CNS Depressants. 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
Pramipexole: CNS Depressants may increase sedative effects of Pramipexole. Risk C: Monitor
Pramlintide: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. These effects are specific to the GI tract. Risk X: Avoid
Procarbazine: May increase CNS depressant effects of CNS Depressants. 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
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
Revefenacin: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Revefenacin. Risk X: Avoid
Rilmenidine: May increase CNS depressant effects of CNS Depressants. 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
Ropeginterferon Alfa-2b: CNS Depressants may increase adverse/toxic effects of Ropeginterferon Alfa-2b. Specifically, the risk of neuropsychiatric adverse effects may be increased. Management: Avoid coadministration of ropeginterferon alfa-2b and other CNS depressants. If this combination cannot be avoided, monitor patients for neuropsychiatric adverse effects (eg, depression, suicidal ideation, aggression, mania). Risk D: Consider Therapy Modification
ROPINIRole: CNS Depressants may increase sedative effects of ROPINIRole. Risk C: Monitor
Rotigotine: CNS Depressants may increase sedative effects of Rotigotine. Risk C: Monitor
Scopolamine: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Scopolamine. Risk C: Monitor
Secnidazole: Products Containing Ethanol may increase adverse/toxic effects of Secnidazole. Risk X: Avoid
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 Inhibitors (Strong CYP2D6 Inhibitors): Dextromethorphan may increase serotonergic effects of Selective Serotonin Reuptake Inhibitors (Strong CYP2D6 Inhibitors). This could result in serotonin syndrome. Selective Serotonin Reuptake Inhibitors (Strong CYP2D6 Inhibitors) may increase serum concentration of Dextromethorphan. Management: Consider alternatives to this drug combination. The dose of dextromethorphan/bupropion product should not exceed 1 tablet once daily. Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity. Risk D: Consider Therapy Modification
Serotonergic Agents (High Risk): Dextromethorphan 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
Sofpironium: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Sofpironium. Risk X: Avoid
Suvorexant: CNS Depressants may increase CNS depressant effects of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Risk D: Consider Therapy Modification
Thalidomide: CNS Depressants may increase CNS depressant effects of Thalidomide. Risk X: Avoid
Thiazide and Thiazide-Like Diuretics: Agents with Clinically Relevant Anticholinergic Effects may increase serum concentration of Thiazide and Thiazide-Like Diuretics. Risk C: Monitor
Thiothixene: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Thiothixene. Risk C: Monitor
Tiapride: Agents with Clinically Relevant Anticholinergic Effects may decrease therapeutic effects of Tiapride. 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
Topiramate: Agents with Clinically Relevant Anticholinergic Effects may increase adverse/toxic effects of Topiramate. Risk C: Monitor
Tranylcypromine: May increase anticholinergic effects of Antihistamines, First Generation. Risk X: Avoid
Trimeprazine: May increase CNS depressant effects of CNS Depressants. 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
Umeclidinium: May increase anticholinergic effects of Agents with Clinically Relevant Anticholinergic Effects. Risk X: Avoid
Valerian: May increase CNS depressant effects of CNS Depressants. Risk C: Monitor
Zolpidem: CNS Depressants may increase CNS depressant effects of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Risk D: Consider Therapy Modification
Zuclopenthixol: Agents with Clinically Relevant Anticholinergic Effects may increase anticholinergic effects of Zuclopenthixol. Risk C: Monitor
Zuranolone: May increase CNS depressant effects of CNS Depressants. Management: Consider alternatives to the use of zuranolone with other CNS depressants or alcohol. If combined, consider a zuranolone dose reduction and monitor patients closely for increased CNS depressant effects. Risk D: Consider Therapy Modification
Refer to individual monographs.
Refer to individual monographs.
Dextromethorphan decreases the sensitivity of cough receptors and interrupts cough impulse transmission by depressing the medullary cough center through sigma receptor stimulation; structurally related to codeine.
Pyrilamine is an H1-receptor antagonist.
Note: No pharmacokinetic data available for this combination.
Pyrilamine: There are no published pharmacokinetic parameters available.
Dextromethorphan: See Dextromethorphan monograph.