Promethazine is an antihistamine.

Pronunciation: pro-METH-a-zeen

What are promethazine’s uses?

Promethazine is used in the treatment of allergy symptoms, for example, a runny nose, itchiness, sneezing, watery eyes, and itchy skin rashes.

It is also used for motion sickness and to treat nausea and vomiting.

What dosage should you take?

The dosage for promethazine will depend on the condition being treated. It is important to not take more or less of this medicine than what is prescribed. To prevent motion sickness, it should typically be taken about an hour before travelling. 

Check the correct dosages with your Clicks pharmacist.

What special precautions should you take?

  • Promethazine may cause side effects that could affect your thinking or reaction time. It may therefore affect your ability to drive or operate machinery. It is advised that you don’t undertake these potentially dangerous activities until you know how this medicine will affect you.
  • Avoid drinking alcohol with this medication.
  • Promethazine should not be given to a child younger than two years old, as it can cause severe breathing problems.
  • Dosage in children depends on their weight, so always be as accurate as possible with this information if this medication is being prescribed for a child.
  • This medication can cause unusual results in certain medical tests, so advise any doctor treating you that you are taking it.
  • Promethazine should be used with caution in the elderly as they are more likely to suffer from the side effects.
  • Promethazine is not safe to use if you are pregnant or planning to become pregnant, or are breastfeeding.

Promethazine should be avoided if you suffer from the following conditions:

  • A promethazine allergy
  • Recurrent bouts of dizziness, drowsiness or headache

Promethazine should be used with caution if you suffer from the following conditions:

  • Asthma
  • Bronchitis
  • Increased eye pressure (glaucoma)
  • Epilepsy
  • Impaired liver or kidney function
  • Prostate problems
  • Diabetes
  • Reye’s syndrome (a rare condition that causes swelling in the liver and brain)

What drug interactions could you experience?

As a rule, always inform your doctor or Clicks pharmacist what prescription and non-prescription medications, vitamins, nutritional supplements and herbal products you are taking or planning to take to ensure you don’t suffer the effects of adverse drug interactions.

What are promethazine’s side effects?

Side effects could include:

  • Dizziness
  • Restlessness
  • Headache
  • Disorientation
  • Dry mouth
  • Nightmares
  • Skin rashes
  • Abdominal pain, indigestion, nausea, vomiting
  • Loss of appetite
  • Sensitivity to light

This is not a complete list of side effects. It’s essential that you call your doctor should you notice any severe or odd side effects.

What are the overdose symptoms?

Call a doctor or the ambulance immediately if you notice the following symptoms:
In children:

  • Decreased coordination
  • Excitability
  • Any involuntary movements
  • Hallucinations
  • Slowed breathing
  • Increase in heart rate

In adults:

  • Drowsiness
  • Convulsions
  • Increased or abnormal heart rate
  • Slowed breathing
The accuracy of this information was checked and approved by Clicks' pharmacist Waheed Abdurahman in August 2015