Chlorpheniramine is an antihistamine that reduces the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.

Chlorpheniramine is used to treat sneezing, itching, watery eyes, and runny nose caused by allergies or the common cold.

Chlorpheniramine may also be used for purposes not listed in this medication guide.

Do not give this medication 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.

Do not take chlorpheniramine if you are allergic to it.

Ask a doctor or pharmacist before taking chlorpheniramine if you have glaucoma, a stomach ulcer, severe constipation, kidney disease, urination problems, an enlarged prostate, or a thyroid disorder.

Ask a doctor or pharmacist before using any other cold, cough, or allergy medicine. Chlorpheniramine is 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.

Chlorpheniramine 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 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.