Skip to Content

Flowtuss Side Effects

Generic Name: guaifenesin / hydrocodone

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

For the Consumer

Applies to guaifenesin/hydrocodone: oral solution

Along with its needed effects, guaifenesin / hydrocodone may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking guaifenesin / hydrocodone:

Incidence Not Known

  • Agitation
  • bladder pain
  • bloating or swelling of the face, arms, hands, lower legs, or feet
  • bloody or cloudy urine
  • changes in vision
  • chills
  • cough
  • darkening of the skin
  • diarrhea
  • difficult, burning, or painful urination
  • difficulty swallowing or breathing
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from lying or sitting position
  • fainting
  • fast heartbeat
  • frequent urge to urinate
  • hives, itching, skin rash
  • irregular, fast or slow, or shallow breathing
  • loss of appetite
  • loss of consciousness
  • mental depression
  • nausea
  • overactive reflexes
  • pains in stomach, side, or abdomen, possibly radiating to the back
  • pale or blue lips, fingernails, or skin
  • poor coordination
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • rapid weight gain
  • restlessness shivering talking or acting with excitement you cannot control
  • tightness in the chest
  • tingling of the hands or feet
  • trembling or shaking twitching
  • unusual weight gain or loss
  • vomiting
  • yellow eyes or skin

Some side effects of guaifenesin / hydrocodone 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:

More Common

  • Diarrhea
  • difficulty having a bowel movement
  • feeling of warmth
  • headache
  • lack or loss of strength
  • nausea
  • redness of the face, neck, arms, and occasionally, upper chest
  • sleepiness or unusual drowsiness
  • stomach pain
  • sudden sweating
  • trouble sleeping

For Healthcare Professionals

Applies to guaifenesin / hydrocodone: oral capsule, oral liquid, oral syrup, oral tablet, oral tablet extended release


The most commonly reported adverse effects have included headache, dizziness, sedation, nausea, diarrhea, decreased blood pressure, and flushing.[Ref]

Nervous system

Frequency not reported: Sedation (somnolence), headache, dizziness, decreased mental alertness with impaired mental and/or physical abilities


-Increased intracranial pressure[Ref]


Frequency not reported: Dose-related respiratory depression including fatal respiratory depression[Ref]


Frequency not reported: Nausea, diarrhea


Frequency not reported: Paralytic ileus[Ref]


Frequency not reported: Hot flush[Ref]


Frequency not reported: Decreased blood pressure[Ref]


Frequency not reported: Mental clouding, anxiety, fear, dysphoria, drug dependence, mood changes, sleeplessness


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

2. "Product Information. Flowtuss (guaifenesin-hydrocodone)." Mission Pharmacal Company, San Antonio, TX.

3. Turturro MA, Paris PM, Yealy DM, Menegazzi JJ "Hydrocodone versus codeine in acute musculoskeletal pain." Ann Emerg Med 20 (1991): 1100-3

4. Morrow PL, Faris EC "Death associated with inadvertent hydrocodone overdose in a child with a respiratory tract infection." Am J Forensic Med Pathol 8 (1987): 60-3

5. Sackner MA "Effects of hydrocodone bitartrate on breathing pattern of patients with chronic obstructive pulmonary disease and restrictive lung disease." Mt Sinai J Med 51 (1984): 222-6

6. Fricke J, Halladay SC, Bynum L, Francisco CA "Pain relief after dental impaction surgery using ketorolac, hydrocodone plus acetaminophen, or placebo." Clin Ther 15 (1993): 500-9

7. "Product Information. Vicodin Tuss (guaifenesin-hydrocodone)" Knoll Pharmaceutical Company, Mount Olive, NJ.

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

9. Sorensen JL, Hargreaves WA, Weinberg JA "Heroin addict responses to six weeks of detoxification with LAAM." Drug Alcohol Depend 9 (1982): 79-87

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.

More about Flowtuss (guaifenesin / hydrocodone)

Consumer resources

Other brands: Narcof, Monte-G HC, Canges-XP, CodiCLEAR DH, ... +5 more

Professional resources

Related treatment guides