Comtrex Non-Drowsy Side Effects
Generic name: acetaminophen / dextromethorphan / pseudoephedrine
Medically reviewed by Drugs.com. Last updated on Aug 20, 2022.
Note: This document contains side effect information about acetaminophen / dextromethorphan / pseudoephedrine. Some of the dosage forms listed on this page may not apply to the brand name Comtrex Non-Drowsy.
For the Consumer
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, swallowing, 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 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
For Healthcare Professionals
Pseudoephedrine causes vasoconstriction which generally does not produce hypertension, but may be problematic for patients with preexisting hypertension. Arrhythmias may be produced in predisposed patients. Rarely, pseudoephedrine has been reported to cause coronary artery spasm and chest pain.
One report evaluated the effect with 60 mg of pseudoephedrine on individuals in a hyperbaric chamber at 1 atmosphere (simulated scuba dive to 66 feet of sea water). Pseudoephedrine and depth (simulated) were found to have significant but opposite effects on heart rate, although these effects were unlikely to be clinically significant during diving.[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.
Gastrointestinal side effects of dextromethorphan have included upset stomach.
Gastrointestinal side effects of pseudoephedrine have included anorexia and gastric irritation in approximately 5% of patients. Dry mouth, nose, or throat have occurred in up to 15% of patients.[Ref]
Hypersensitivity side effects of dextromethorphan have included rare reports of fixed-drug eruptions.
Hypersensitivity side effects of pseudoephedrine have included fixed drug eruptions.[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]
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).
Frequently asked questions
More about Comtrex Non-Drowsy (acetaminophen / dextromethorphan / pseudoephedrine)
- Drug interactions
- Dosage information
- During pregnancy
- Drug images
- Drug class: upper respiratory combinations
Related treatment guides
1. Mariani PJ "Pseudoephedrine-induced hypertensive emergency: treatment with labetalol." Am J Emerg Med 4 (1986): 141-2
2. Rosen RA "Angina associated with pseudoephedrine ." Ann Emerg Med 10 (1981): 230-1
3. Wiener I, Tilkian AG, Palazzolo M "Coronary artery spasm and myocardial infarction in a patient with normal coronary arteries: temporal relationship to pseudoephedrine ingestion." Cathet Cardiovasc Diagn 20 (1990): 51-3
4. Gordon RD, Ballantine DM, Bachmann AW "Effects of repeated doses of pseudoephedrine on blood pressure and plasma catecholamines in normal subjects and in patients with phaeochromocytoma." Clin Exp Pharmacol Physiol 19 (1992): 287-90
5. Stroh JE, Jr Ayars GH, Bernstein IL, Kemp JP, Podleski WK, Prenner BM, Schoenwetter WF, Salzmann JK "A comparative tolerance study of terfenadine-pseudoephedrine combination tablets and pseudoephedrine tablets in patients with allergic or vasomotor rhinitis." J Int Med Res 16 (1988): 420-7
6. Dickerson J, Perrier D, Mayersohn M, Bressler R "Dose tolerance and pharmacokinetic studies of L (+) pseudoephedrine capsules in man." Eur J Clin Pharmacol 14 (1978): 253-9
7. Lyon CC, Turney JH "Pseudoephedrine toxicity in renal failure." Br J Clin Pract 50 (1996): 396-7
8. Knowles SR, Weber E "Dextromethorphan anaphylaxis." J Allerg Clin Immunol 102 (1998): 316-7
9. Mores N, Campia U, Navarra P, Cardillo C, Preziosi P "No cardiovascular effects of single-dose pseudoephedrine in patients with essential hypertension treated with beta-blockers." Eur J Clin Pharmacol 55 (1999): 251-4
10. Gill ND, Shield A, Blazevich AJ, Zhou S, Weatherby RP "Muscular and cardiorespiratory effects of pseudoephedrine in human athletes." Br J Clin Pharmacol 50 (2000): 205-13
11. Taylor DM, O'Toole KS, Auble TE, Ryan CM, Sherman DR "The psychometric and cardiac effects of pseudoephedrine in the hyperbaric environment." Pharmacotherapy 20 (2000): 1045-50
12. Hall RC, Beresford TP, Stickney SK, Nasdahl CS, Coleman JH "Psychiatric reactions produced by respiratory drugs." Psychosomatics 26 (1985): 605-8,616-7
13. Loizou LA, Hamilton JG, Tsementzis SA "Intracranial haemorrhage in association with pseudoephedrine overdose." J Neurol Neurosurg Psychiatry 45 (1982): 471-2
14. Helfer J, Kim OM "Psychoactive abuse potential of Robitussin-DM." Am J Psychiatry 147 (1990): 672-3
15. Covington TR, eds., Lawson LC, Young LL "Handbook of Nonprescription Drugs." Washington, DC: American Pharmaceutical Association (1993):
16. Murray S, Brewerton T "Abuse of over-the-counter dextromethorphan by teenagers." South Med J 86 (1993): 1151-3
17. Wolfe TR, Caravati EM "Massive dextromethorphan ingestion and abuse." Am J Emerg Med 13 (1995): 174-6
18. Polles A, Griffith JL "Dextromethorphan-induced mania." Psychosomatics 37 (1996): 71-4
19. Bostwick JM "Dextromethorphan-induced manic symptoms in a bipolar patient on lithium." Psychosomatics 37 (1996): 571-2
20. Dowd J, Bailey D, Moussa K, Nair S, Doyle R, CulpepperMorgan JA "Ischemic colitis associated with pseudoephedrine: Four cases." Am J Gastroenterol 94 (1999): 2430-4
21. Stubb S, Reitamo S "Fixed-drug eruption due to dextromethorphan ." Arch Dermatol 126 (1990): 970-1
22. Shelley WB, Shelley ED "Nonpigmenting fixed drug eruption as a distinctive reaction pattern: examples caused by sensitivity to pseudoephedrine hydrochloride and tetrahydrozoline." J Am Acad Dermatol 17 (1987): 403-7
23. Tomb RR, Lepoittevin JP, Espinassouze F, Heid E, Foussereau J "Systemic contact dermatitis from pseudoephedrine." Contact Dermatitis 24 (1991): 86-8
24. Camisa C "Fixed drug eruption due to pseudoephedrine." Cutis 41 (1988): 339-40
25. Quan MB, Chow WC "Nonpigmenting fixed drug eruption after pseudoephedrine." Int J Dermatol 35 (1996): 367-70
26. Vidal C, Prieto A, PerezCarral C, Armisen M "Nonpigmenting fixed drug eruption due to pseudoephedrine." Ann Allergy Asthma Immunol 80 (1998): 309-10
27. 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
28. O'Dell JR, Zetterman RK, Burnett DA "Centrilobular hepatic fibrosis following acetaminophen-induced hepatic necrosis in an alcoholic." JAMA 255 (1986): 2636-7
29. Seeff LB, Cuccherini BA, Zimmerman HJ, Adler E, Benjamin SB "Acetaminophen hepatotoxicity in alcoholics." Ann Intern Med 104 (1986): 399-404
30. Keaton MR "Acute renal failure in an alcoholic during therapeutic acetaminophen ingestion." South Med J 81 (1988): 1163-6
31. Kumar S, Rex DK "Failure of physicians to recognize acetaminophen hepatotoxicity in chronic alcoholics." Arch Intern Med 151 (1991): 1189-91
32. McJunkin B, Barwick KW, Little WC, Winfield JB "Fatal massive hepatic necrosis following acetaminophen overdose." JAMA 236 (1976): 1874-5
33. Zimmerman HJ, Maddrey WC "Acetaminophen (paracetamol) hepatotoxicity with regular intake of alcohol: analysis of instances of therapeutic misadventure." Hepatology 22 (1995): 767-73
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.