Promethazine

What is Promethazine for?

Promethazine belongs to a group of medicines known as antihistamines. It can be used for the following conditions:

• Relief of redness and swelling of the skin and eyes
• Relief of itch in the eyes, nose or skin (due to an insect bite or allergies)
• Relief of runny nose and sneezing      
• Treat nausea and vomiting
• Prevent or treat motion sickness
• Help you to fall asleep

Promethazine may be used for other conditions. Check with your healthcare professional if you are unsure why you are given this medication.

You can also find out about this medication by watching these videos:
They are available in English, 中文, Melayu and தமிழ்: Antihistamines(oral)

How should I take or use Promethazine?

This medication may be taken with or without food. 

Take this medication when necessary to relieve your symptoms.

Do not exceed the maximum dose as recommended by your healthcare professional.

What should I do if I forget to take or use Promethazine?

As the medicine is to be taken only on an “as-needed” basis; there is no need to take the medication if you are not experiencing any symptoms.

What precautions should I take when taking or using Promethazine?

Inform your healthcare professional if:

• You are allergic to this medication or any of the other ingredients of this medication.
• You are pregnant, planning to become pregnant, or breastfeeding. If you are pregnant and/or breastfeeding, your doctor would have discussed the potential benefits and side-effects with you and should you have further questions or concerns, do consult your doctor.
• You are taking any other medications (including those that can be bought without a prescription), supplements, traditional medications and herbal remedies. Some of them may affect how this medication works or cause serious drug interactions.
• You have or have ever had:
  • Increased eye pressure (glaucoma)
  • Difficulty in urinating or have a history of other bladder conditions
  • Stomach ulcers
  • Seizures  
  • Kidney, liver, respiratory or thyroid diseases
  • High blood pressure or abnormal heart rhythm

What food or medication should I avoid when I take or use Promethazine?

Avoid alcoholic drinks as this may increase drowsiness.

Avoid taking sedating medications as this medicine may increase the drowsy effects.

Do not take with or within 14 days of stopping monoamine oxidase inhibitors (MAOIs).

Many over-the-counter medications contain antihistamines, always check with your health care professional before taking two over-the-counter medications at the same time to prevent overdosing.

What are some common side effects of Promethazine?

• Drowsiness or feeling tired
  • Avoid driving or taking part in activities that require concentration.
  • Discuss with your doctor if you can take your medication at a different time of the day.
• Dizziness
  • Get up slowly from a sitting or lying down position.
• Dry mouth
  • Chew sugar-free gum, suck on sugar-free hard candies or ice chips, or take sips of water regularly.
• Constipation
  • Drink more water (if you do not have any fluid restriction), eat more high-fibre foods, and exercise regularly.
  • Speak to your doctor or pharmacist if you need medication to help with your constipation.
• Headache
• Difficulty in passing urine or constipation
  • Stop taking this medication and consult your healthcare professional for alternatives.

Most of the side effects listed here will improve with time. Speak with your doctor if any of them continues, worsens or affects your daily life.

What are some rare but serious side effects that I need to seek medical advice immediately?

The symptoms of a drug allergy include one or more of the following:

• Swollen face/eyes/lips/tongue
• Difficulty in breathing
• Itchy skin rashes over your whole body

You can also find out about drug allergies by watching these videos:
They are available in English, 中文, Melayu and தமிழ்: Drug Allergies

Rarely, this medication may cause:

• Restless muscle movements in your eyes, tongue, jaw or neck (dyskinesia)
• Confusion, high fever, severe muscle stiffness, irregular blood pressure (signs and symptoms of neuroleptic malignant syndrome)
• Seeing or hearing things that are not there (hallucinations)
• Confusion
• Fast or irregular heartbeat, fainting episodes (signs and symptoms of an abnormal heart beating rhythm (prolonged QTc interval))
• Tremors
• Seizures (fits)
• Blurred vision

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

If you continue to experience symptoms for more than 2 weeks even with self-treatment or have any of the following symptoms:

• Blood in your phlegm or mucous
• Unexplained weight loss, constant fatigue, night sweats

Your condition may be too serious for self-treatment and you should consult a doctor.

How should I store Promethazine?

Store in a cool and dry place below 30°C, away from direct sunlight. Keep this medication away from children.

How do I throw away Promethazine safely?

Pack this medication into a trash bag and seal it tightly before throwing into the rubbish chute or bin.