Promethazine

This form:

Pronounced

"pro-METH-uh-zeen"

Common brand names:

Histantil

Uses

See also Warning section.

Promethazine is used to prevent and treat nausea and vomiting related to certain conditions (such as before/after surgery, motion sickness). It is also used to treat allergy symptoms such as rash, itching, and runny nose. It may be used to help you feel sleepy/relaxed before and after surgery or to help certain opioid pain relievers (such as meperidine) work better. It may also be used for a short time to treat a runny nose due to the common cold.

Promethazine is an antihistamine and works by blocking a certain natural substance (histamine) that your body makes during an allergic reaction. Its other effects (such as anti-nausea, calming, pain relief) may work by affecting other natural substances (such as acetylcholine) and by acting directly on certain parts of the brain.

Cough-and-cold products have not been shown to be safe or effective in children younger than 6 years. Do not use this product to treat cold symptoms in children younger than 6 years unless specifically directed by the doctor. Some products (such as long-acting tablets/capsules) are not recommended for use in children younger than 12 years. Ask your doctor or pharmacist for more details about using your product safely.

These products do not cure or shorten the length of the common cold and may cause serious side effects. To decrease the risk for serious side effects, carefully follow all dosage directions. Do not give other cough-and-cold medication that might contain the same or similar ingredients (see also Drug Interactions section). Ask the doctor or pharmacist about other ways to relieve cough and cold symptoms (such as drinking enough fluids, using a humidifier or saline nose drops/spray).

How to Use This Medication

Read the Patient Information Leaflet if available from your pharmacist before you start taking promethazine and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually 2 to 4 times daily. For motion sickness, the first dose of promethazine should be taken 30 to 60 minutes before beginning travel. For allergies, this medication may be taken once daily at bedtime to avoid being drowsy during the day. When used before surgery, promethazine may be taken the night before or just before the procedure and may be continued afterwards as directed.

If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.

The dosage is based on your age, medical condition, and response to treatment. Children's dosage may also be based on weight. Do not increase your dose or take this medication more often than directed.

Tell your doctor if your condition does not improve or if it worsens.

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