Acetaminophen / dextromethorphan / guaifenesin / phenylephrine Side Effects
For the Consumer
Applies to acetaminophen / dextromethorphan / guaifenesin / phenylephrine: oral capsule, oral liquid, oral tablet
What are some side effects that I need to call my doctor about right away?
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 or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Not able to pass urine or change in how much urine is passed.
- A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
What are some other side effects of this drug?
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:
- Feeling nervous and excitable.
- Not able to sleep.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
For Healthcare Professionals
Applies to acetaminophen / dextromethorphan / guaifenesin / phenylephrine: oral capsule, oral liquid, oral powder for reconstitution, oral tablet
Cardiovascular side effects of phenylephrine have included palpitations, arrhythmias, and cardiovascular collapse with hypotension.[Ref]
Gastrointestinal side effects of dextromethorphan have included upset stomach.
Gastrointestinal side effects of guaifenesin have included stomach upset and vomiting with higher than recommended doses. Doses recommended for expectoration have rarely been associated with gastrointestinal upset.
Gastrointestinal side effects of phenylephrine have included nausea.[Ref]
General side effects of phenylephrine have included pallor and weakness.[Ref]
Genitourinary side effects of phenylephrine have included dysuria.[Ref]
Hepatic side effects of acetaminophen have included severe and sometimes fatal dose dependent hepatitis in alcoholic patients. Hepatotoxicity has been increased during fasting.[Ref]
Hypersensitivity side effects of dextromethorphan have included rare reports of fixed-drug eruptions.[Ref]
Nervous system side effects of dextromethorphan have included drowsiness and dizziness. Other side effects such as excitation, mental confusion, and opioid like respiratory depression have been rare and occurred at higher dosages. In some cases of abuse, patients experienced euphoria, hyperactivity, mania, and auditory and visual hallucinations.
Nervous system side effects of guaifenesin have occasionally included dizziness and headache.
Nervous system side effects of phenylephrine have included headache, dizziness, nervousness, restlessness, tremor, insomnia, convulsions, and central nervous system depression.[Ref]
Psychiatric side effects of phenylephrine have included hallucinations, fear, and anxiety.[Ref]
Respiratory side effects of phenylephrine have included respiratory difficulty.[Ref]
Dermatologic side effects associated with acetaminophen includes the risk of rare but potentially fatal serious skin reactions known as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP).
Dermatologic side effects of guaifenesin have included rare reports of rash.[Ref]
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3. Wolfe TR, Caravati EM "Massive dextromethorphan ingestion and abuse." Am J Emerg Med 13 (1995): 174-6
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5. O'Dell JR, Zetterman RK, Burnett DA "Centrilobular hepatic fibrosis following acetaminophen-induced hepatic necrosis in an alcoholic." JAMA 255 (1986): 2636-7
6. Keaton MR "Acute renal failure in an alcoholic during therapeutic acetaminophen ingestion." South Med J 81 (1988): 1163-6
7. Seeff LB, Cuccherini BA, Zimmerman HJ, Adler E, Benjamin SB "Acetaminophen hepatotoxicity in alcoholics." Ann Intern Med 104 (1986): 399-404
8. Kaysen GA, Pond SM, Roper MH, Menke DJ, Marrama MA "Combined hepatic and renal injury in alcoholics during therapeutic use of acetaminophen." Arch Intern Med 145 (1985): 2019-23
9. McJunkin B, Barwick KW, Little WC, Winfield JB "Fatal massive hepatic necrosis following acetaminophen overdose." JAMA 236 (1976): 1874-5
10. Zimmerman HJ, Maddrey WC "Acetaminophen (paracetamol) hepatotoxicity with regular intake of alcohol: analysis of instances of therapeutic misadventure." Hepatology 22 (1995): 767-73
11. Kumar S, Rex DK "Failure of physicians to recognize acetaminophen hepatotoxicity in chronic alcoholics." Arch Intern Med 151 (1991): 1189-91
12. Stubb S, Reitamo S "Fixed-drug eruption due to dextromethorphan ." Arch Dermatol 126 (1990): 970-1
13. Helfer J, Kim OM "Psychoactive abuse potential of Robitussin-DM." Am J Psychiatry 147 (1990): 672-3
14. Bostwick JM "Dextromethorphan-induced manic symptoms in a bipolar patient on lithium." Psychosomatics 37 (1996): 571-2
15. Polles A, Griffith JL "Dextromethorphan-induced mania." Psychosomatics 37 (1996): 71-4
16. Hall RC, Beresford TP, Stickney SK, Nasdahl CS, Coleman JH "Psychiatric reactions produced by respiratory drugs." Psychosomatics 26 (1985): 605-8,616-7
17. Murray S, Brewerton T "Abuse of over-the-counter dextromethorphan by teenagers." South Med J 86 (1993): 1151-3
18. "Product Information. Robitussin (guaifenesin)." Wyeth-Ayerst Laboratories, Philadelphia, PA.
Some side effects of acetaminophen / dextromethorphan / guaifenesin / phenylephrine may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.
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