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Codeine, Phenylephrine, and Triprolidine

Index Terms

  • Codeine Phosphate, Phenylephrine Hydrochloride, and Triprolidine Hydrochloride
  • Phenylephrine, Triprolidine, and Codeine
  • Triprolidine, Codeine, and Phenylephrine

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Syrup, Oral:

Histex-AC: Codeine phosphate 10 mg, phenylephrine hydrochloride 10 mg, and triprolidine hydrochloride 2.5 mg per 5 mL (473 mL) [alcohol free, dye free, sugar free; contains methylparaben, propylene glycol, propylparaben; bubble-gum flavor]

Brand Names: U.S.

  • Histex-AC [OTC]

Pharmacologic Category

  • Alkylamine Derivative
  • Alpha/Beta Agonist
  • Analgesic, Opioid
  • Antitussive
  • Decongestant
  • Histamine H1 Antagonist
  • Histamine H1 Antagonist, First Generation

Pharmacology

See individual agents.

Use: Labeled Indications

Common cold or upper respiratory allergies: Temporarily relieves symptoms due to common cold, hay fever (allergic rhinitis), or other upper respiratory allergies

Contraindications

OTC labeling: When used for self-medication, do not use if you are taking a monoamine oxidase inhibitor (MAOI), or for 2 weeks after stopping the MAOI

Dosing: Adult

Common cold or upper respiratory allergies: Oral: Histex AC (codeine 10 mg, phenylephrine 10 mg, and triprolidine 2.5 mg per 5 mL): 5 mL every 4 hours (maximum: 20 mL per 24 hours)

Dosing: Pediatric

Common cold or upper respiratory allergies: Oral: Histex AC (codeine 10 mg, phenylephrine 10 mg, and triprolidine 2.5 mg per 5 mL):

Children 6 to <12 years: 2.5 mL every 4 hours (maximum: 10 mL per 24 hours)

Children ≥12 years and Adolescents: Refer to adult dosing

Dosing: Renal Impairment

There are no dosage adjustments provided in the manufacturer’s labeling.

Dosing: Hepatic Impairment

There are no dosage adjustments provided in the manufacturer’s labeling.

Storage

Store at 15°C to 30°C (59°F to 86°F).

Drug Interactions

AbobotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of AbobotulinumtoxinA. Monitor therapy

Acetaminophen: May increase the serum concentration of Phenylephrine (Systemic). Monitor therapy

Acetylcholinesterase Inhibitors: May diminish the therapeutic effect of Anticholinergic Agents. Anticholinergic Agents may diminish the therapeutic effect of Acetylcholinesterase Inhibitors. Monitor therapy

Aclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Monitor therapy

Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha1-Agonists. Similarly, Alpha1-Agonists may antagonize Alpha1-Blocker vasodilation. Monitor therapy

Alvimopan: Analgesics (Opioid) may enhance the adverse/toxic effect of Alvimopan. This is most notable for patients receiving long-term (i.e., more than 7 days) opiates prior to alvimopan initiation. Management: Alvimopan is contraindicated in patients receiving therapeutic doses of opioids for more than 7 consecutive days immediately prior to alvimopan initiation. Consider therapy modification

Amphetamines: May enhance the analgesic effect of Analgesics (Opioid). Monitor therapy

Amphetamines: May diminish the sedative effect of Antihistamines. Monitor therapy

Analgesics (Opioid): Anticholinergic Agents may enhance the adverse/toxic effect of Analgesics (Opioid). Specifically, the risk for constipation and urinary retention may be increased with this combination. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of other Anticholinergic Agents. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of Analgesics (Opioid). Specifically, the risk for constipation and urinary retention may be increased with this combination. Monitor therapy

Antipsychotic Agents (Phenothiazines): May enhance the hypotensive effect of Analgesics (Opioid). Monitor therapy

AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Benzylpenicilloyl Polylysine: Antihistamines may diminish the diagnostic effect of Benzylpenicilloyl Polylysine. 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. Consider therapy modification

Benzylpenicilloyl Polylysine: Alpha1-Agonists may diminish the diagnostic effect of Benzylpenicilloyl Polylysine. Management: Consider use of a histamine skin test as a positive control to assess a patient's ability to mount a wheal and flare response. Consider therapy modification

Betahistine: Antihistamines may diminish the therapeutic effect of Betahistine. Monitor therapy

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cimetropium: Anticholinergic Agents may enhance the anticholinergic effect of Cimetropium. Avoid combination

CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Monitor therapy

CYP2D6 Inhibitors (Moderate): May diminish the therapeutic effect of Codeine. These CYP2D6 inhibitors may prevent the metabolic conversion of codeine to its active metabolite morphine. Monitor therapy

CYP2D6 Inhibitors (Strong): May diminish the therapeutic effect of Codeine. These CYP2D6 inhibitors may prevent the metabolic conversion of codeine to its active metabolite morphine. Consider therapy modification

Desmopressin: Analgesics (Opioid) may enhance the adverse/toxic effect of Desmopressin. Monitor therapy

Dimethindene: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Diuretics: Analgesics (Opioid) may enhance the adverse/toxic effect of Diuretics. Analgesics (Opioid) may diminish the therapeutic effect of Diuretics. Monitor therapy

Doxofylline: Sympathomimetics may enhance the adverse/toxic effect of Doxofylline. Monitor therapy

Doxylamine: May enhance the CNS depressant effect of CNS Depressants. Management: The manufacturer of Diclegis (doxylamine/pyridoxine), intended for use in pregnancy, specifically states that use with other CNS depressants is not recommended. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (e.g., opioids, barbiturates) with concomitant use. Consider therapy modification

Eluxadoline: Analgesics (Opioid) may enhance the constipating effect of Eluxadoline. Avoid combination

Eluxadoline: Anticholinergic Agents may enhance the constipating effect of Eluxadoline. Avoid combination

Ergot Derivatives: May enhance the hypertensive effect of Alpha1-Agonists. Ergot Derivatives may enhance the vasoconstricting effect of Alpha1-Agonists. Exceptions: Ergoloid Mesylates; Nicergoline. Avoid combination

FentaNYL: Alpha1-Agonists may decrease the serum concentration of FentaNYL. Specifically, fentanyl nasal spray serum concentrations may decrease and onset of effect may be delayed. Monitor therapy

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification

Gastrointestinal Agents (Prokinetic): Anticholinergic Agents may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy

Glucagon: Anticholinergic Agents may enhance the adverse/toxic effect of Glucagon. Specifically, the risk of gastrointestinal adverse effects may be increased. Avoid combination

Glycopyrrolate (Oral Inhalation): Anticholinergic Agents may enhance the anticholinergic effect of Glycopyrrolate (Oral Inhalation). Avoid combination

Hyaluronidase: May enhance the vasoconstricting effect of Phenylephrine (Systemic). Management: Avoid the use of hyaluronidase to enhance dispersion or absorption of phenylephrine. Use of hyaluronidase for other purposes in patients receiving phenylephrine may be considered as clinically indicated. Avoid combination

HYDROcodone: CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Consider starting with a 20% to 30% lower hydrocodone dose when using together with any other CNS depressant. Dose reductions in the other CNS depressant may also be warranted. Consider therapy modification

HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Iobenguane I 123: Sympathomimetics may diminish the therapeutic effect of Iobenguane I 123. Avoid combination

Ioflupane I 123: Phenylephrine (Systemic) may diminish the diagnostic effect of Ioflupane I 123. Monitor therapy

Ipratropium (Oral Inhalation): May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Itopride: Anticholinergic Agents may diminish the therapeutic effect of Itopride. Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Levosulpiride: Anticholinergic Agents may diminish the therapeutic effect of Levosulpiride. Avoid combination

Linezolid: May enhance the hypertensive effect of Sympathomimetics. Management: Reduce initial doses of sympathomimetic agents, and closely monitor for enhanced pressor response, in patients receiving linezolid. Specific dose adjustment recommendations are not presently available. Consider therapy modification

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

MAO Inhibitors: May enhance the hypertensive effect 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. Exceptions: Linezolid; Tedizolid. Avoid combination

MAO Inhibitors: May enhance the adverse/toxic effect of Codeine. Monitor therapy

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

Mianserin: May enhance the anticholinergic effect of Anticholinergic Agents. Monitor therapy

Minocycline: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mirabegron: Anticholinergic Agents may enhance the adverse/toxic effect of Mirabegron. Monitor therapy

Mirtazapine: CNS Depressants may enhance the CNS depressant effect of Mirtazapine. Monitor therapy

Mixed Agonist / Antagonist Opioids: May diminish the analgesic effect of Analgesics (Opioid). Management: Seek alternatives to mixed agonist/antagonist opioids in patients receiving pure opioid agonists, and monitor for symptoms of therapeutic failure/high dose requirements (or withdrawal in opioid-dependent patients) if patients receive these combinations. Avoid combination

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Nalmefene: May diminish the therapeutic effect of Analgesics (Opioid). Management: Avoid the concomitant use of nalmefene and opioid analgesics. Discontinue nalmefene 1 week prior to any anticipated use of opioid analgesics. If combined, larger doses of opioid analgesics will likely be required. Consider therapy modification

Naltrexone: May diminish the therapeutic effect of Analgesics (Opioid). Management: Seek therapeutic alternatives to opioids. See full drug interaction monograph for detailed recommendations. Consider therapy modification

OnabotulinumtoxinA: Anticholinergic Agents may enhance the anticholinergic effect of OnabotulinumtoxinA. Monitor therapy

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination

Oxatomide: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: When oxycodone is combined with another CNS depressant, a dose reduction of one or both agents should be considered. The extended release oxycodone starting dose should be reduced 50% to 67% when initiated in patients already receiving CNS depressants. Consider therapy modification

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Pegvisomant: Analgesics (Opioid) may diminish the therapeutic effect of Pegvisomant. Monitor therapy

Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification

Piribedil [INT]: CNS Depressants may enhance the CNS depressant effect of Piribedil [INT]. Monitor therapy

Potassium Chloride: Anticholinergic Agents may enhance the ulcerogenic effect of Potassium Chloride. Management: Patients on drugs with substantial anticholinergic effects should avoid using any solid oral dosage form of potassium chloride. Avoid combination

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

Pramlintide: May enhance the anticholinergic effect of Anticholinergic Agents. These effects are specific to the GI tract. Consider therapy modification

Propacetamol: May increase the serum concentration of Phenylephrine (Systemic). Management: Monitor patients closely for increased side effects of phenylephrine if propacetamol is used concomitantly. Patients with underlying blood pressure issues or arrhythmias may need closer monitoring and may warrant consideration of alternative therapies. Monitor therapy

Ramosetron: Anticholinergic Agents may enhance the constipating effect of Ramosetron. Monitor therapy

Ramosetron: Analgesics (Opioid) may enhance the constipating effect of Ramosetron. Monitor therapy

RimabotulinumtoxinB: Anticholinergic Agents may enhance the anticholinergic effect of RimabotulinumtoxinB. Monitor therapy

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Secretin: Anticholinergic Agents may diminish the therapeutic effect of Secretin. Management: Avoid using drugs with substantial anticholinergic effects in patients receiving secretin whenever possible. If such agents must be used in combination, monitor closely for a diminished response to secretin. Consider therapy modification

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Serotonin Modulators: Analgesics (Opioid) may enhance the serotonergic effect of Serotonin Modulators. This could result in serotonin syndrome. Exceptions: Nicergoline. Monitor therapy

Sodium Oxybate: May enhance the CNS depressant effect of CNS Depressants. Management: Consider alternatives to combined use. When combined use is needed, consider minimizing doses of one or more drugs. Use of sodium oxybate with alcohol or sedative hypnotics is contraindicated. Consider therapy modification

Somatostatin Analogs: May decrease the metabolism of Codeine. The formation of two major codeine metabolites (morphine and norcodeine) may be impaired by somatostatin analogs. Monitor therapy

Succinylcholine: May enhance the bradycardic effect of Analgesics (Opioid). Monitor therapy

Suvorexant: CNS Depressants may enhance the CNS depressant effect 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. Consider therapy modification

Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy

Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Start tapentadol at a dose of one-third to one-half of the normal dose if being initiated in a patient who is taking another drug with CNS depressant effects. Monitor closely for evidence of excessive CNS depression. Consider therapy modification

Tedizolid: May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Thiazide and Thiazide-Like Diuretics: Anticholinergic Agents may increase the serum concentration of Thiazide and Thiazide-Like Diuretics. Monitor therapy

Tiotropium: Anticholinergic Agents may enhance the anticholinergic effect of Tiotropium. Avoid combination

Topiramate: Anticholinergic Agents may enhance the adverse/toxic effect of Topiramate. Monitor therapy

Tricyclic Antidepressants: May enhance the vasopressor effect of Alpha1-Agonists. Tricyclic Antidepressants may diminish the vasopressor effect of Alpha1-Agonists. Monitor therapy

Trimeprazine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Umeclidinium: May enhance the anticholinergic effect of Anticholinergic Agents. Avoid combination

Zolpidem: CNS Depressants may enhance the CNS depressant effect 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. Consider therapy modification

Adverse Reactions

See individual agents.

Warnings/Precautions

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 which require mental alertness (eg, operating machinery or driving).

• Constipation: Use may cause or aggravate constipation

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

• Sedatives: Effects may be potentiated when used with other sedative drugs or ethanol.

Special populations:

• Pediatric: Antihistamines may cause excitation in young children.

Other warnings/precautions:

• Appropriate use: When used for self-medication (OTC use), contact health care provider prior to use if you have breathing problems (eg, chronic bronchitis, emphysema, or other chronic pulmonary disease), persistent or chronic cough (eg, cough associated with asthma, emphysema, smoking), a cough with excessive mucus, diabetes, glaucoma, heart disease, hypertension, difficulty urinating due to enlarged prostate, or thyroid disease. Discontinue use and contact health care provider if new symptoms develop; if cough or nasal symptoms persist for >1 week, recur, or are accompanied by a fever, rash, or persistent headache; if dizziness, nervousness, or sleepiness occur. Do not exceed recommended dosage.

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience anxiety, insomnia, or sweating a lot. Have patient report immediately to prescriber severe dizziness, passing out, angina, tachycardia, difficulty breathing, slow breathing, shallow breathing, noisy breathing, severe fatigue, confusion, arrhythmia, hallucinations, mood changes, seizures, severe abdominal pain, severe headache, difficulty passing urine, tremors, vision changes, severe nausea, severe vomiting, severe constipation, or severe loss of strength and energy (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.

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