Promethazine (Phenergan) belongs to a group of medicines known as sedating antihistamines. It has several uses.
It is used to prevent (or treat) feelings of sickness (nausea). It is commonly recommended for sickness associated with travel and for vertigo.
It is also used to relieve allergies such as hay fever and allergic skin rashes.
Promethazine also makes you feel sleepy (has a sedative effect). It may be taken (for a few days only) to help promote sleep in adults with sleeping problems. It has been popular in the past as a means of 'settling' children, but promethazine should not be used in this way.
Promethazine is available on prescription, or you can buy it without a prescription from White Pharmacy. It is not suitable for children under 2 years of age.
Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. There are a number of different brands and strengths of promethazine tablet. The manufacturer's leaflet will give you more information about the brand you have been given. It will also contain a full list of the side-effects which you may experience from taking promethazine.
Take promethazine exactly as your doctor or pharmacist has told you to. You may be asked to take one or more doses during a day, depending upon the reason why you are taking it.
Children 2-5 years: See your local pharmacy for Phenergan Elixir for this age group.
Children 5-10 years:
Phenergan 10mg Tablets - Either a single dose of 1 or two tablets at night or 1 tablet twice daily. The total dose must not exceed 2 tablets per day.
Phenergan 25mg Tablets - A single night time dose of 1 tablet. The total dose must not exceed 1 tablet per day.
Children over 10 years & Adults:
Phenergan 10mg Tablets - Start with one tablet twice a day, this may be increased to a maximum of two tablets three times a day if necessary.
Phenergan 25mg Tablets - A single daily dose of one tablet at night increasing to a maximum of 1 tablet twice daily if necessary.
You can take Phenergan before or after meals. Some people find it helps to swallow the tablets with a drink of water.
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains the most common one associated with promethazine. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any continue or become troublesome.
Common promethazine side-effects
- Feeling dizzy or sleepy, and blurred vision
- Dry mouth
- Difficulty passing urine
- Stomach upset, constipation
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.
To make sure this is the right treatment for you, before you start taking promethazine it is important that you discuss the treatment with a doctor or pharmacist if:
- You are pregnant, trying for a baby or breastfeeding.
- You have a problem with the way your liver works, or if you have a problem with your kidneys.
- You have a condition which causes increased pressure in your eyes, such as glaucoma.
- You have prostate problems or if you have been experiencing any difficulty passing urine.
- You know you have a blockage in your small intestines.
- You have epilepsy.
- You have any long-term breathing problems, such as asthma or chronic obstructive pulmonary disease (COPD).
- You are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
- You have ever had an allergic reaction to a medicine.
The patient information leaflet (PIL) is a leaflet containing specific information about medical conditions, doses and side effects. You can download a copy of the PIL here:
Patient Info Leaflet