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Ephedrine and Guaifenesin

Medically reviewed by Drugs.com. Last updated on Jun 9, 2020.

Pronunciation

(e FED rin & gwye FEN e sin)

Index Terms

  • Guaifenesin and Ephedrine

Dosage Forms

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

Tablet, Oral:

Bronkaid: Ephedrine sulfate 25 mg and guaifenesin 400 mg

Primatene Asthma: Ephedrine sulfate 12.5 mg and guaifenesin 200 mg [scored]

Brand Names: U.S.

  • Bronkaid [OTC]
  • Primatene Asthma [OTC]

Pharmacologic Category

  • Expectorant/Decongestant

Pharmacology

Ephedrine: Releases tissue stores of norepinephrine and thereby produces an alpha- and beta-adrenergic stimulation; longer-acting and less potent than epinephrine

Guaifenesin: Thought to act as an expectorant by irritating the gastric mucosa and stimulating respiratory tract secretions, thereby increasing respiratory fluid volumes and decreasing mucous viscosity

Contraindications

OTC labeling: When used for self-medication, do not use if asthma is not confirmed by a health care provider; coadministration with a monoamine oxidase inhibitor (MAOI) or 2 weeks after discontinuing an MAOI; hypersensitivity to ephedrine, guaifenesin, or any component of the formulation.

Administration

Administer without regard to food.

Storage

Store at 20° to 25°C (68° to 77°F).

Drug Interactions

Alkalinizing Agents: May increase the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. Similarly, Alpha-/Beta-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

Atropine (Systemic): May enhance the therapeutic effect of EPHEDrine (Systemic). Monitor therapy

Benzylpenicilloyl Polylysine: Alpha-/Beta-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

Bretylium: May enhance the therapeutic effect of Alpha-/Beta-Agonists (Direct-Acting). Monitor therapy

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

Carbonic Anhydrase Inhibitors: May increase the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Cardiac Glycosides: EPHEDrine (Systemic) may enhance the arrhythmogenic effect of Cardiac Glycosides. Monitor therapy

Chloroprocaine: May enhance the hypertensive effect of Alpha-/Beta-Agonists. Monitor therapy

CloNIDine: May enhance the therapeutic effect of EPHEDrine (Systemic). Monitor therapy

CloZAPine: May diminish the therapeutic effect of Alpha-/Beta-Agonists. 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

DexAMETHasone (Systemic): EPHEDrine (Systemic) may decrease the serum concentration of DexAMETHasone (Systemic). Monitor therapy

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

Droxidopa: EPHEDrine (Systemic) may enhance the hypertensive effect of Droxidopa. Monitor therapy

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

FentaNYL: Alpha-/Beta-Agonists (Indirect-Acting) 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 Alpha-/Beta-Agonists. Management: Avoid the use of hyaluronidase to enhance dispersion or absorption of alpha-/beta-agonists. Use of hyaluronidase for other purposes in patients receiving alpha-/beta-agonists may be considered as clinically indicated. Consider therapy modification

Inhalational Anesthetics: EPHEDrine (Systemic) may enhance the arrhythmogenic effect of Inhalational Anesthetics. Avoid combination

Iobenguane Radiopharmaceutical Products: Alpha-/Beta-Agonists (Indirect-Acting) 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

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 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. Exceptions: Linezolid. Avoid combination

Oxytocin: May enhance the hypertensive effect of EPHEDrine (Systemic). Monitor therapy

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

Propofol: May enhance the therapeutic effect of EPHEDrine (Systemic). Monitor therapy

QuiNIDine: May diminish the therapeutic effect of EPHEDrine (Systemic). EPHEDrine (Systemic) may diminish the therapeutic effect of QuiNIDine. Monitor therapy

Reserpine: May diminish the therapeutic effect of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Rocuronium: EPHEDrine (Systemic) may enhance the therapeutic effect of Rocuronium. Monitor therapy

Serotonin/Norepinephrine Reuptake Inhibitors: May enhance the tachycardic effect of Alpha-/Beta-Agonists. Serotonin/Norepinephrine Reuptake Inhibitors may enhance the vasopressor effect of Alpha-/Beta-Agonists. Management: If possible, avoid coadministration of direct-acting alpha-/beta-agonists and serotonin/norepinephrine reuptake inhibitors. If coadministered, monitor for increased sympathomimetic effects (eg, increased blood pressure, chest pain, headache). Consider therapy modification

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

Spironolactone: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. 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 vasopressor effect of Alpha-/Beta-Agonists. Management: Avoid, if possible, the use of alpha-/beta-agonists in patients receiving tricyclic antidepressants. If combined, monitor for evidence of increased pressor effects and consider reductions in initial dosages of the alpha-/beta-agonist. Consider therapy modification

Urinary Acidifying Agents: May decrease the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Adverse Reactions

Frequency not defined.

Cardiovascular: Hypertension, tachycardia

Central nervous system: Emotional disturbance, headache, insomnia, nervousness, seizure

Hypersensitivity: Hypersensitivity reaction

Neuromuscular & skeletal: Tremor

Respiratory: Cough, exacerbation of asthma, productive cough

Warnings/Precautions

Concerns related to adverse effects:

• Cardiovascular effect: May cause hypertension or tachycardia, increasing the risk of myocardial infarction (MI) and/or stroke. Serious cardiovascular events (eg, MI, stroke, arrhythmias), including deaths, have been previously reported with use of dietary supplements containing ephedra alkaloids (Haller, 2000).

Disease-related concerns:

• Asthma: Only use with a diagnosis of asthma; notify health care provider if asthma becomes worse during use. Inhaled bronchodilators provide more rapid symptomatic relief of asthma than ephedrine/guaifenesin.

• Cardiovascular disease: Use with caution in patients with heart disease and/or hypertension.

• Diabetes: Use with caution in patients with diabetes mellitus.

• Glaucoma: Use with caution in patients with narrow angle glaucoma.

• Prostatic hyperplasia/urinary stricture: Use with caution in patients with prostatic hyperplasia and/or urinary stricture.

• Psychiatric conditions: Use with caution in patients with psychiatric or emotional conditions.

• Seizures: Use with caution in patients with a history of seizure disorder.

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

Special populations:

• Pediatric: Not for OTC use in children <12 years.

Pregnancy Considerations

Refer to individual monographs.

Patient Education

What is this drug used for?

• It is used to treat asthma.

• 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:

• Trouble sleeping

• Tremors

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:

• Severe headache

• Severe dizziness

• Passing out

• Vision changes

• Chest pain

• Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight

• Fast heartbeat

• Seizures

• Severe anxiety

• 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.