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Fenesin Side Effects

Generic Name: guaifenesin

Note: This document contains side effect information about guaifenesin. Some of the dosage forms listed on this page may not apply to the brand name Fenesin.

For the Consumer

Applies to guaifenesin: oral capsule, oral capsule extended release, oral elixir, oral liquid, oral packet, oral solution, oral syrup, oral tablet, oral tablet extended release

Along with its needed effects, guaifenesin (the active ingredient contained in Fenesin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Some side effects of guaifenesin may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less Common or Rare

For Healthcare Professionals

Applies to guaifenesin: compounding powder, oral capsule, oral capsule extended release, oral granule, oral liquid, oral solution, oral tablet, oral tablet extended release

General

Guaifenesin (the active ingredient contained in Fenesin) has been generally well tolerated.[Ref]

Gastrointestinal

Gastrointestinal side effects have included stomach upset and vomiting with higher than recommended doses. Doses recommended for expectoration have rarely been associated with gastrointestinal upset.[Ref]

Nervous system

Nervous system side effects have occasionally included dizziness and headache.[Ref]

Dermatologic

Dermatologic side effects have included rare reports of rash.[Ref]

Hypersensitivity

Hypersensitivity side effects have included a report of an anaphylactic reaction.[Ref]

References

1. Covington TR, Lawson LC, Young LL, eds. "Handbook of Nonprescription Drugs. 10th ed." Washington, DC: American Pharmaceutical Association (1993):

2. "Product Information. Robitussin (guaifenesin)." Wyeth-Ayerst Laboratories, Philadelphia, PA.

3. Manujendra R, Faltay B, Haller NA "Case report: anaphylactic reaction to guaifenesin." Hosp Pract 37 (2009): 60-3

Further information

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

Some side effects may not be reported. You may report them to the FDA.

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