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Guaifenesin and Phenylephrine

Medically reviewed by Drugs.com. Last updated on Mar 3, 2020.

Pronunciation

(gwye FEN e sin & fen il EF rin)

Index Terms

  • Guaifenesin and Phenylephrine Tannate
  • Guaifenesin/Phenylephrine HCl
  • Phenylephrine Hydrochloride and Guaifenesin

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Liquid, oral:

Ed Bron GP: Guaifenesin 100 mg and phenylephrine hydrochloride 5 mg per 5 mL (480 mL) [dye free, ethanol free, sugar free; contains propylene glycol; orange flavor]

Mucinex Children's Stuffy Nose & Cold: Guaifenesin 100 mg and phenylephrine hydrochloride 2.5 mg per 5 mL (118 mL) [contains edetate disodium, fd&c red #40, propylene glycol, and sodium benzoate; mixed berry flavor]

Nu-COPD: Guaifenesin 200 mg and phenylephrine hydrochloride 10 mg per 5 mL (480 mL [DSC])

Syrup, oral:

J-Max: Guaifenesin 200 mg and phenylephrine hydrochloride 5 mg per 5 mL (473 mL [DSC]) [ethanol free, sugar free; contains propylene glycol; strawberry cream flavor]

Triaminic Children's Chest & Nasal Congestion: Guaifenesin 50 mg and phenylephrine hydrochloride 2.5 mg per 5 mL (118 mL) [contains benzoic acid, propylene glycol, sodium 3 mg/5 mL; tropical flavor]

Tablet, oral:

Ambi 10PEH/400GFN: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

Deconex IR: Guaifenesin 385 mg and phenylephrine hydrochloride 10 mg [contains tartrazine]

Fenesin PE IR: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

Gcon IR: Guaifenesin 385 mg and phenylephrine hydrochloride 10 mg

Medent-PEI: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

MucaphEd: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg [DSC]

Mucus Relief Sinus: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

Nu-COPD: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

OneTab Congestion & Cold: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

Refenesen PE: Guaifenesin 400 mg and phenylephrine hydrochloride 10 mg

Relcof IR: Guaifenesin 380 mg and phenylephrine hydrochloride 10 mg [DSC]

Sudafed PE Non-Drying Sinus: Guaifenesin 200 mg and phenylephrine hydrochloride 5 mg [DSC]

Brand Names: U.S.

  • Ambi 10PEH/400GFN [OTC]
  • Deconex IR [OTC]
  • Ed Bron GP [OTC]
  • Fenesin PE IR
  • Gcon IR [OTC]
  • J-Max [OTC] [DSC]
  • Medent®-PEI [OTC]
  • MucaphEd [OTC] [DSC]
  • Mucinex Children's Stuffy Nose & Cold
  • Mucus Relief Sinus [OTC]
  • Nu-COPD [OTC] [DSC]
  • OneTab Congestion & Cold [OTC]
  • Refenesen PE [OTC]
  • Relcof IR [OTC] [DSC]
  • Sudafed PE Non-Drying Sinus [OTC] [DSC]
  • Triaminic Children's Chest & Nasal Congestion [OTC]

Pharmacologic Category

  • Decongestant
  • Expectorant

Pharmacology

See individual agents.

Use: Labeled Indications

Expectorant/decongestant: Temporary relief of nasal congestion, sneezing, nasal/throat irritation, and itchy/watery eyes associated with common cold, hay fever, or other respiratory allergies; loosens mucus and thins bronchial secretions making coughs more productive; reduces swelling of nasal passages

Contraindications

Concurrent administration with or within 2 weeks of discontinuing an MAO inhibitor

Dosing: Adult

Expectorant/decongestant: Oral: Dosing may vary by product; consult specific product labeling.

Liquid:

Guaifenesin 50 mg/phenylephrine 2.5 mg per 5 mL: 20 mL every 4 hour; maximum: 120 mL per 24 hours.

Guaifenesin 100 mg/phenylephrine 5 mg per 5 mL: 10 mL every 4 hours; maximum: 60 mL per 24 hours.

Tablet: Guaifenesin 385 mg/phenylephrine 10 mg per tablet: One tablet every 4 hours; maximum: 6 tablets per 24 hours.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Cold/allergy symptoms: Note: Multiple concentrations of oral liquid formulations and solid oral dosage forms exist; close attention must be paid to the concentration when ordering or administering.

Liquid:

Guaifenesin 100 mg and phenylephrine 2.5 mg per 5 mL (eg, Mucinex Children's Stuffy Nose and Cold):

Children ≥4 years to <6 years: Oral: 5 mL every 4 hours; maximum daily dose: 30 mL/24 hours

Children ≥6 years to <12 years: Oral: 10 mL every 4 hours; maximum daily dose: 60 mL/24 hours

Guaifenesin 100 mg and phenylephrine 5 mg per 5 mL (eg, Ed Bron GP):

Children ≥6 years to <12 years: Oral: 5 mL every 4 hours; maximum daily dose: 30 mL/24 hours

Children ≥12 years and Adolescents: Oral: 10 mL every 4 hours; maximum daily dose: 60 mL/24 hours

Tablet:

Guaifenesin 385 mg and phenylephrine 10 mg per tablet (eg, Deconex IR):

Children ≥6 years to <12 years: Oral: 1/2 tablet every 4 hours; maximum daily dose: 3 tablets/24 hours

Children ≥12 years and Adolescents: Oral: 1 tablet every 4 hours; maximum daily dose: 6 tablets/24 hours

Guaifenesin 400 mg and phenylephrine 10 mg per tablet (eg, Mucus Relief D): Children ≥12 years and Adolescents: Oral: 1 tablet every 4 hours; maximum daily dose: 6 tablets/24 hours

Dietary Considerations

May be taken with or without food. Taking with food, water or milk may help decrease gastric irritation. Some products may contain sodium.

Storage

Store at 15°C to 30°C (59°F to 86°F).

Drug Interactions

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

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

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

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

Cannabinoid-Containing Products: May enhance the tachycardic effect of Sympathomimetics. Exceptions: Cannabidiol. Monitor therapy

Chloroprocaine: May enhance the hypertensive effect of Phenylephrine (Systemic). Monitor therapy

CloZAPine: May diminish the therapeutic effect of Phenylephrine (Systemic). Monitor therapy

Cocaine (Topical): May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification

Disulfiram: May enhance the adverse/toxic effect of Products Containing Ethanol. Management: Do not use disulfiram with dosage forms that contain ethanol. Avoid combination

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

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

Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. Monitor therapy

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

Iobenguane Radiopharmaceutical Products: Alpha1-Agonists may diminish the therapeutic effect 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. Avoid combination

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

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

Methotrimeprazine: Products Containing Ethanol may enhance the adverse/toxic effect of Methotrimeprazine. Specifically, CNS depressant effects may be increased. Management: Avoid products containing alcohol in patients treated with methotrimeprazine. Avoid combination

Monoamine Oxidase 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. Avoid combination

Ozanimod: May enhance the hypertensive effect of Sympathomimetics. Management: Concomitant use of ozanimod with sympathomimetic agents is not recommended. If combined, monitor patients closely for the development of hypertension, including hypertensive crises. Consider therapy modification

Procarbazine: May enhance the adverse/toxic effect of Sympathomimetics. Management: Consider alternatives to this combination when possible. Procarbazine prescribing information states that this combination should be avoided. 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

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

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

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

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

Adverse Reactions

See individual agents.

Warnings/Precautions

Disease-related concerns:

• Cardiovascular disease: Use with caution in patients with cardiovascular disease (including hypertension and ischemic heart disease); contraindicated with severe 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 GU obstruction.

• Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.

Special populations:

• Elderly: Use with caution in the elderly; may be more sensitive to adverse effects.

Dosage form specific issues:

• Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggest that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer's labeling.

• Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures, and respiratory depression; use caution (AAP ["Inactive" 1997]; Zar 2007).

Other warnings/precautions:

• Cough: Appropriate use: Underlying cause of cough should be determined prior to prescribing.

• Self-medication (OTC use): When used for self-medication (OTC), do not exceed recommended doses; discontinue use and contact health care provider if symptoms do not improve within 7 days or are accompanied by fever; if nervousness, dizziness, or sleeplessness occur; or if new symptoms occur.

Pregnancy Considerations

Refer to individual monographs.

Patient Education

What is this drug used for?

• It is used to treat nose stuffiness.

• It is used to thin mucus so it can be taken from the body by coughing.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Dizziness

• Anxiety

• Trouble sleeping

• Fatigue

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.