Alka-Seltzer Plus Cold Powerfast Fizz Night

Generic name: aspirin, dextromethorphan, doxylamine, and phenylephrine [ AS-pir-in, DEX-troe-meth-OR-fan, dox-IL-a-meen, and-FEN-il-EF-rin ]
Brand names: Alka-Seltzer Plus Cold Powerfast Fizz Night, Alka-Seltzer Plus Severe Cold Powerfast Fizz Day and Night
Drug class: Upper respiratory combinations

Medically reviewed by Drugs.com on Jan 12, 2024. Written by Cerner Multum.

What is Alka-Seltzer Plus Cold Powerfast Fizz Night?

Alka-Seltzer Plus Cold Powerfast Fizz Night is a combination medicine used in adults and children at least 12 years old to temporarily relieve minor aches and pains, headaches, runny nose, sinus congestion and pressure, cough, sneezing, sore throat, nasal congestion, and fever caused by the common cold.

Alka-Seltzer Plus Cold Powerfast Fizz Night may also be used for purposes not listed in this medication guide.

Alka-Seltzer Plus Cold Powerfast Fizz Night side effects

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Alka-Seltzer Plus Cold Powerfast Fizz Night may cause serious side effects. Call your doctor at once if you have:

• severe sore throat that lasts for more than 2 days, or followed by fever, headache, rash, nausea, or vomiting.

Alka-Seltzer Plus Cold Powerfast Fizz Night may cause serious side effects. Stop using Alka-Seltzer Plus Cold Powerfast Fizz Night and call your doctor at once if you have:

• stomach bleeding--bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;

• stomach pain that does not go away;

• pain, cough, or nasal congestion that gets worse or lasts more than 7 days;

• fever that gets worse or lasts more than 3 days;

• redness or swelling;

• ringing in the ears or hearing loss;

• cough returns or occurs with rash or headache; or

• nervousness, dizziness, or sleep problems.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

Do not use this medicine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, and tranylcypromine.

Before taking this medicine

You should not use Alka-Seltzer Plus Cold Powerfast Fizz Night if you are allergic to it, or to any other pain reliever or fever reducer.

Do not use Alka-Seltzer Plus Cold Powerfast Fizz Night if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, and tranylcypromine.

Using Alka-Seltzer Plus Cold Powerfast Fizz Night in a child or teenager with flu symptoms or chickenpox can cause a serious or fatal condition called Reye's syndrome.

Ask a doctor or pharmacist if this medicine is safe to use if you have or have ever had:

• stomach ulcers or bleeding problems;

• stomach problems such as heartburn;

• if you are age 60 or older;

• a habit of drinking more than 3 alcoholic beverages per day;

• high blood pressure, or heart disease;

• asthma;

• emphysema or chronic bronchitis;

• diabetes;

• thyroid disorder;

• glaucoma;

• cough with or without mucus;

• problems with urination;

• if you are on a low-salt diet; or

• liver or kidney disease.

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

How should I take Alka-Seltzer Plus Cold Powerfast Fizz Night?

Use exactly as directed on the label, or as prescribed by your doctor. Cold or cough medicine is only for short-term use.

Take 2 tablets fully dissolved in 4 ounces (120 mL) of water every 4 to 6 hours.

Do not take more than 4 tablets in 12 hours or 8 tablets in 24 hours unless told otherwise by your doctor.

Wait 4 hours after taking the last Night dose before taking the Day product.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Alka-Seltzer Plus Cold Powerfast Fizz Night is used when needed. If you are on a dosing schedule, skip any missed dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Alka-Seltzer Plus Cold Powerfast Fizz Night?

Drinking alcohol with Alka-Seltzer Plus Cold Powerfast Fizz Night can cause side effects.

Ask a doctor or pharmacist before taking other cough or cold medicines that may contain similar ingredients.

Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.

What other drugs will affect Alka-Seltzer Plus Cold Powerfast Fizz Night?

Using Alka-Seltzer Plus Cold Powerfast Fizz Night with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Ask a doctor or pharmacist before using Alka-Seltzer Plus Cold Powerfast Fizz Night with any other medicines, especially:

• gout medication;

• arthritis medication;

• diabetes medications;

• a diuretic or "water pill";

• steroids;

• a blood thinner--warfarin, Coumadin, Jantoven; or

• NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may affect Alka-Seltzer Plus Cold Powerfast Fizz Night, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Copyright 1996-2025 Cerner Multum, Inc. Version: 1.02.