Promethazine Overview

Generic Name: Promethazine (oral)
Drug Classes: Antihistamines, Phenothiazine antiemetics

What is Promethazine?

Promethazine belongs to a group of drugs called phenothiazines, which work by altering chemicals in the brain. It also acts as an antihistamine by blocking the effects of histamine, a naturally occurring chemical in the body.

Uses:

• Treats allergy symptoms (itching, runny nose, sneezing, itchy or watery eyes, hives, and skin rashes)
• Prevents motion sickness
• Treats nausea, vomiting, and pain after surgery
• Used as a sedative or sleep aid

Note: Promethazine is not suitable for treating symptoms of asthma, pneumonia, or other lower respiratory tract infections.

Warnings

• Severe Side Effects: Stop using promethazine and contact your doctor if you experience twitching or uncontrollable movements of your eyes, lips, tongue, face, arms, or legs. These could be early signs of serious side effects.
• Children: Do not give promethazine to children under 2 years old due to the risk of severe breathing problems or death. Follow your doctor’s instructions carefully when giving this medicine to children of any age.
• Impaired Thinking: Promethazine may impair your thinking or reactions. Exercise caution if you need to drive or perform tasks requiring alertness.
• Alcohol: Avoid alcohol as it can increase some side effects of promethazine.
• Medication Interactions: Promethazine can interact with many medications. Inform your doctor about all prescription, over-the-counter medications, vitamins, minerals, herbal products, and any other drugs you are using.

Before Taking Promethazine

Do not take promethazine if you are allergic to it or other similar medicines (e.g., chlorpromazine, fluphenazine, mesoridazine). Inform your doctor if you have:

• Respiratory conditions (e.g., asthma, COPD, sleep apnea)
• A history of seizures
• Weak immune system
• Glaucoma
• Enlarged prostate
• Stomach ulcer or obstruction
• Heart disease or high blood pressure
• Liver disease
• Adrenal gland tumor (pheochromocytoma)
• Low calcium levels (hypocalcemia)
• A history of serious side effects from phenothiazines

Pregnancy and Breastfeeding:

• The effects of promethazine on an unborn baby are unknown. Consult your doctor if you are pregnant or planning to become pregnant.
• It is not known if promethazine passes into breast milk. Breastfeeding while using this medicine is not recommended.

How to Take Promethazine

• Take promethazine exactly as prescribed by your doctor.
• For motion sickness, take promethazine within 1 hour before traveling.
• When used for surgery, it is usually taken the night before.
• Measure liquid medicine accurately with a dosing syringe or special measuring device.
• Doses in children are based on weight; inform your doctor of any weight changes.

Missed Dose: Take the missed dose as soon as you remember. Skip it if it’s nearly time for the next dose. Do not double up doses.

Overdose: Seek emergency help or contact the Poison Help line.

What to Avoid

• Avoid driving or activities requiring alertness if you feel drowsy or dizzy.
• Rise slowly from sitting or lying positions to prevent dizziness.
• Avoid alcohol, which can enhance side effects.
• Stay out of direct sunlight, as promethazine increases sun sensitivity.

Side Effects

Serious Side Effects (Seek medical attention immediately):

• Severe drowsiness, weak or shallow breathing
• Confusion, agitation, hallucinations, nightmares
• Seizures
• Fast or slow heartbeats
• Jaundice (yellowing of skin or eyes)
• Uncontrolled muscle movements
• Easy bruising or bleeding

Common Side Effects:

• Drowsiness, dizziness
• Ringing in your ears
• Double vision
• Feeling nervous
• Dry mouth
• Sleep problems (insomnia)

Note: This is not an exhaustive list of side effects. Contact your doctor for medical advice about side effects. Report side effects to FDA.

Drug Interactions

Promethazine can interact with many medications. Some key interactions include:

• Medications: Lithium, atropine, blood pressure medications, bronchodilators, bladder or urinary medications, MAO inhibitors, Parkinson’s disease medications, and stomach ulcer medications.

Always keep a list of your current medications and share it with any healthcare provider treating you. Do not start new medications without consulting your doctor.

Note: 

The brand name displayed above is specific to this product. Brand names can vary depending on the manufacturer.