Reviewed on 8/16/2021

What Is Aspirin/Chlorpheniramine/Dextromethorphan and How Does It Work?

Aspirin/chlorpheniramine/dextromethorphan is an over-the-counter (OTC) product used for temporary relief of common cold cough and upper respiratory symptoms.

Aspirin/chlorpheniramine/dextromethorphan is available under the following different brand names: Alka-Seltzer Plus Flu.

What Are the Dosages of Aspirin/Chlorpheniramine/Dextromethorphan?

Dosages of Aspirin/Chlorpheniramine/Dextromethorphan:

Dosage Forms and Strengths

Tablet, Effervescent

  • 500mg/2mg/15mg

Dosage Considerations – Should be Given as Follows:

Temporary Relief of Common Cold Cough and Upper Respiratory Symptoms

Alka-Seltzer Plus Flu:

  • Adults and children over 12 years: 2 tablets fully dissolved in 4 oz of water every 6 hours; not to exceed 8 tablets/day
  • Children under 12 years: Ask a pediatrician

What Are Side Effects Associated with Using Aspirin/Chlorpheniramine/Dextromethorphan?

Side effects of aspirin/chlorpheniramine/dextromethorphan include:

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.


Which illness is known as a viral upper respiratory tract infection? See Answer

What Other Drugs Interact with Aspirin/Chlorpheniramine/Dextromethorphan?

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

Severe interactions of aspirin/chlorpheniramine/dextromethorphan include:

Aspirin/chlorpheniramine/dextromethorphan has serious interactions with at least 63 different drugs.

Aspirin/chlorpheniramine/dextromethorphan has moderate interactions with at least 498 different drugs.

Aspirin/chlorpheniramine/dextromethorphan has mild interactions with at least 115 different drugs.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

What Are Warnings and Precautions for Aspirin/Chlorpheniramine/Dextromethorphan? 


This medication contains aspirin/chlorpheniramine/dextromethorphan. Do not take Alka-Seltzer Plus Flu if you are allergic to aspirin/chlorpheniramine/dextromethorphan or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.


  • Hypersensitivity
  • Liver damage
  • Hypoprothrombinemia
  • Vitamin K deficiency
  • Bleeding disorders
  • Asthma
  • Due to the association of aspirin with Reye syndrome, do not use in children (under 16 years) with viral infections
  • Narrow-angle glaucoma
  • Symptomatic prostate hypertrophy
  • Bladder-neck obstruction
  • Stenosing peptic ulcer

Effects of Drug Abuse

  • No information available

Short-Term Effects

  • See "What Are Side Effects Associated with Using Aspirin/Chlorpheniramine/Dextromethorphan?”

Long-Term Effects

  • See "What Are Side Effects Associated with Using Aspirin/Chlorpheniramine/Dextromethorphan?”


  • Aspirin may cause a transient decrease in renal function and aggravate chronic kidney disease; avoid use in patients with severe anemia, with a history of blood coagulation defects, or taking anticoagulants
  • Dextromethorphan: do not take for persistent or chronic cough associated with smoking, asthma, or emphysema, or if it is accompanied by excessive phlegm unless directed by a healthcare provider; may slow respiration rate
  • Chlorpheniramine: may cause significant confusional symptoms; not for administration to premature or full-term neonates

Pregnancy and Lactation

Use aspirin/chlorpheniramine/dextromethorphan during pregnancy only in LIFE-THREATENING emergencies when no safer drug is available. There is positive evidence of human fetal risk. Avoid aspirin during pregnancy, particularly in the third trimester (risk of premature closure of ductus arteriosus).

Aspirin/chlorpheniramine/dextromethorphan is excreted in breast milk. Do not breastfeed.

Pregnant or breastfeeding patients should seek the advice of a health professional before using over-the-counter (OTC) drugs.


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