Comtrex Non-Drowsy

Since this medicine is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

Other drugs may interact with acetaminophen, dextromethorphan, and pseudoephedrine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Applies to acetaminophen / dextromethorphan / pseudoephedrine: oral capsule, oral liquid, oral tablet

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.

Applies to acetaminophen / dextromethorphan / pseudoephedrine: oral capsule, oral liquid, oral powder for reconstitution, oral syrup, oral tablet, oral tablet chewable

Cardiovascular

Cardiovascular side effects of pseudoephedrine have included tachycardia. Some patients have developed hypertension and/or arrhythmias.[Ref]

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

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 pseudoephedrine have included insomnia in up to 30% of patients. Tremor, anxiety, nervousness, and headache have also been reported.[Ref]

Gastrointestinal

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

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

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

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).

Some side effects of Comtrex Non-Drowsy may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.