Dimetapp

Generic name: brompheniramine and phenylephrine [ BROM-fen-IR-a-meen-and-FEN-il-EFF-rin ]
Other brand names of brompheniramine and phenylephrine include: Dimetapp Cold & Allergy
Drug class: Upper respiratory combinations

Medically reviewed by Melisa Puckey, BPharm. Last updated on Mar 1, 2024.

What is Dimetapp Cold & Allergy?

Dimetapp Cold & Allergy contains a combination of brompheniramine and phenylephrine. Brompheniramine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Phenylephrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).

Dimetapp Cold & Allergy is used to treat symptoms of the common cold or seasonal allergies, including sneezing, runny or stuffy nose, and itchy, watery eyes.

Dimetapp Cold & Allergy may also be used for purposes not listed in this medication guide.

Warnings

Do not use Dimetapp if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

Do not give Dimetapp Cold & Allergy to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Before taking this medicine

Do not use Dimetapp if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

You should not use Dimetapp Cold & Allergy if you are allergic to brompheniramine or phenylephrine.

Ask a doctor or pharmacist if it is safe for you to take Dimetapp Cold & Allergy if you have:

• asthma or COPD, cough with mucus, or cough caused by smoking, emphysema, or chronic bronchitis;

• a blockage in your stomach or intestines;

• kidney or liver disease;

• high blood pressure, heart disease, coronary artery disease, or recent heart attack;

• enlarged prostate or urination problems;

• glaucoma;

• diabetes;

• epilepsy or other seizure disorder;

• pheochromocytoma (an adrenal gland tumor);

• overactive thyroid; or

• if you take potassium (Cytra, Epiklor, K-Lyte, K-Phos, Kaon, Klor-Con, Polycitra, Urocit-K).

FDA pregnancy category C. It is not known whether Dimetapp Cold & Allergy will harm an unborn baby. Do not use Dimetapp Cold & Allergy without your doctor's advice if you are pregnant.

It is not known whether brompheniramine and phenylephrine passes into breast milk or if it could harm a nursing baby. Antihistamines and decongestants may also slow breast milk production. Do not use Dimetapp Cold & Allergy without your doctor's advice if you are breast-feeding a baby.

Older adults may be more likely to have side effects from Dimetapp Cold & Allergy.

Artificially sweetened liquid cold medicine may contain phenylalanine. If you have phenylketonuria (PKU), check the medication label to see if the product contains phenylalanine.

How should I take Dimetapp Cold & Allergy?

Use Dimetapp exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended. Cold medicine is usually taken only for a short time until your symptoms clear up.

Do not give Dimetapp Cold & Allergy to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Measure Dimetapp Cold & Allergy with a special dose-measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Call your doctor if your symptoms do not improve after 7 days of treatment, or if you have a fever with a headache, cough, or skin rash.

Dimetapp Cold & Allergy can cause unusual results with allergy skin tests. Tell any doctor who treats you that you are taking an antihistamine.

If you need surgery, tell the surgeon ahead of time if you have taken Dimetapp within the past few days.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since cold medicine is taken as needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

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

What to avoid

Dimetapp Cold & Allergy may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol can increase certain side effects of Dimetapp Cold & Allergy.

Ask a doctor or pharmacist before using any other cold, allergy, or sleep medicine. Brompheniramine and phenylephrine are contained in many combination medicines. Taking certain products together can cause you to get too much of a certain drug. Check the label to see if a medicine contains an antihistamine or decongestant.

Dimetapp Cold & Allergy side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Dimetapp: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using Dimetapp Cold & Allergy and call your doctor at once if you have:

• chest pain, rapid pulse, fast or uneven heart rate;

• confusion, hallucinations, severe nervousness;

• tremor, seizure (convulsions);

• little or no urinating;

• easy bruising or bleeding, unusual weakness; or

• dangerously high blood pressure (severe headache, buzzing in your ears, anxiety, shortness of breath).

Common Dimetapp side effects may include:

• dizziness, drowsiness, blurred vision;

• dry nose or mouth;

• nausea, stomach pain, constipation, loss of appetite;

• problems with memory or concentration; or

• feeling restless or excited (especially in children).

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

What other drugs will affect Dimetapp Cold & Allergy?

Ask a doctor or pharmacist before using Dimetapp Cold & Allergy if you are also using any other drugs, including prescription and over-the-counter medicines, vitamins, and herbal products. Some medicines can cause unwanted or dangerous effects when used together. Not all possible interactions are listed in this medication guide.

Taking this medicine with other drugs that make you sleepy or slow your breathing can worsen these effects. Ask your doctor before taking Dimetapp Cold & Allergy with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Dimetapp 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

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