In this Article

• What is chlorpheniramine (Chlor-Trimeton)?
• What are the possible side effects of chlorpheniramine?
• What is the most important information I should know about chlorpheniramine?
• What should I discuss with my healthcare provider before taking chlorpheniramine?
• How should I take chlorpheniramine?
• What happens if I miss a dose?
• What happens if I overdose?
• What should I avoid while taking chlorpheniramine?
• What other drugs will affect chlorpheniramine?
• Where can I get more information?

What should I discuss with my healthcare provider before taking chlorpheniramine?

Do not take this medication if you are allergic to chlorpheniramine.

Do not use chlorpheniramine if you have used an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have:

• glaucoma;
• a stomach ulcer;
• severe constipation;
• kidney disease;
• urination problems or an enlarged prostate; or
• a thyroid disorder.

FDA pregnancy category B. Chlorpheniramine is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Chlorpheniramine can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Older adults may be more likely to have side effects from this medication.

How should I take chlorpheniramine?

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. Cold or allergy medicine is usually taken only for a short time until your symptoms clear up.

Take this medication with a full glass of water.

Take chlorpheniramine with food or milk if it upsets your stomach.

Do not crush, chew, break, or open an extended-release tablet or capsule. Swallow it whole. Breaking or opening 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 cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

This medication can cause unusual results with allergy skin tests. Tell any doctor who treats you that you are taking an antihistamine.

Store at room temperature away from moisture and heat.