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Chlor-Trimeton

Generic name: chlorpheniramine

Brand names: Aller-Chlor, Allergy Relief (Chlorpheniramine), Ed-Chlor Ped Jr, Wal-finate, Allergy Relief, C.P.M, Chlo-Amine, Chlor-Mal, Chlor-Trimeton, ChlorTan, Ed ChlorPed, Ed-Chlortan, PediaTan, Triaminic Allergy

Used for common cold
Last updated November 1, 2026 0 views
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What is Chlor-Trimeton?

Chlor-Trimeton is an antihistamine that decreases the effects of the natural chemical histamine in the body. Histamine can cause symptoms like sneezing, itching, watery eyes, and a runny nose.

Chlor-Trimeton is used to treat a runny nose, sneezing, itching, and watery eyes due to allergies, the common cold, or the flu.

Chlor-Trimeton may also be used for other reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

How should I take Chlor-Trimeton?

Use 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. Chlor-Trimeton is usually taken only for a short time until your symptoms clear up.

Do not take for longer than 7 days in a row. Talk with your doctor if your symptoms do not improve after 7 days of treatment, or if you have a fever with a headache or skin rash.

Do not crush, chew, or break an extended-release tablet. Swallow it whole. Breaking the pill may cause too much of the drug to be released at one time.

Measure liquid medicine 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.

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.

If you need surgery or medical tests, tell the surgeon or doctor ahead of time if you have taken this medicine within the past few days.

Store at room temperature away from moisture and heat. Do not allow the liquid form of this medicine to freeze.

This section was rewritten for readability and reviewed for meaning.

Warnings

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.

You should not use Chlor-Trimeton if you have narrow-angle glaucoma, a blockage in your stomach or intestines, an enlarged prostate, if you are unable to urinate, or if you are having an asthma attack.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use Chlor-Trimeton if you are allergic to it, or if you have:

  • narrow-angle glaucoma;
  • a blockage in your stomach or intestines;
  • an enlarged prostate;
  • if you are unable to urinate; or
  • if you are having an asthma attack.

Ask a doctor or pharmacist if it is safe for you to take Chlor-Trimeton if you have:

  • a blockage in your digestive tract (stomach or intestines), a colostomy or ileostomy;
  • liver or kidney disease;
  • asthma or COPD, cough with mucus, or cough caused by smoking, emphysema, or chronic bronchitis;
  • high blood pressure, heart disease, coronary artery disease, or recent heart attack;
  • epilepsy or other seizure disorder;
  • urination problems;
  • pheochromocytoma (an adrenal gland tumor); or
  • overactive thyroid.

FDA pregnancy category B. Chlor-Trimeton is not expected to harm an unborn baby. Do not use this medicine without your doctor's advice if you are pregnant.

Chlorpheniramine may pass into breast milk and may harm a nursing baby. Antihistamines may also slow breast milk production. Do not use this medicine without your doctor's advice if you are breast-feeding a baby.

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

This section was rewritten for readability and reviewed for meaning.

Chlor-Trimeton side effects

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

Chlor-Trimeton may cause serious side effects. Stop using Chlor-Trimeton and call your doctor right away if you have:

  • fast or uneven heart rate;
  • mood changes;
  • tremor, seizure (convulsions);
  • easy bruising or bleeding, unusual weakness;
  • feeling short of breath; or
  • little or no urinating.

Common side effects of Chlor-Trimeton may include:

  • dizziness, drowsiness;
  • dry mouth, nose, or throat;
  • constipation;
  • blurred vision; or
  • feeling nervous or restless.

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.

This section was rewritten for readability and reviewed for meaning.

What happens if I miss a dose?

Since this medicine is taken as needed, you might not have a regular dosing schedule. If you are taking the medication regularly and miss a dose, take it as soon as you remember. If it is almost time for your next scheduled dose, skip the missed dose. Do not take extra medicine to make up for the missed dose.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

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

Overdose symptoms may include severe forms of some of the side effects listed in this medication guide.

Chlor-Trimeton may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Drinking alcohol can increase certain side effects of chlorpheniramine.

Ask a doctor or pharmacist before using any other cold, cough, allergy, or sleep medicine. Antihistamines 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.

Avoid becoming overheated or dehydrated during exercise and in hot weather. Chlor-Trimeton can decrease sweating and you may be more prone to heat stroke.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect Chlor-Trimeton?

Taking Chlor-Trimeton with other drugs that cause sleepiness or slow your breathing can make these effects worse. Talk to your doctor before using this medicine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medication for anxiety, depression, or seizures.

Check with a doctor or pharmacist before using this medicine if you are also taking any other drugs, including prescription and over-the-counter medicines, vitamins, and herbal products. Some medicines can lead to unwanted or dangerous effects when taken together. Not all possible interactions are listed in this medication guide.

This section was rewritten for readability and reviewed for meaning.

Common questions about Chlor-Trimeton

Which antihistamines make you drowsy?
First-generation antihistamines, like Benadryl (diphenhydramine) and Chlor-Trimeton (chlorpheniramine), often cause sedation. This can include drowsiness, fatigue, and reduced alertness or concentration. Continue reading
Can you take antihistamines when pregnant?
According to the American College of Obstetricians and Gynecologists (ACOG), several over-the-counter (OTC) antihistamines may be taken during pregnancy. Older, first-generation antihistamines can be taken, but they may cause drowsiness. Newer, second-generation antihistamines can also be taken and have less risk of drowsiness. Continue reading

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Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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Content is provided for education and is not medical advice. See our medical disclaimer.