NZ Formulary

Levomepromazine (injection)


What does it do?

Levomepromazine is used to treat nausea and vomiting, some mental health problems, and sometimes other conditions.

Before you start

  • Tell your doctor if you have heart, liver, bowel, bladder or prostate problems.
  • Tell your doctor if you have diabetes, Parkinson’s disease, angle-closure glaucoma, have ever had a seizure, blood clot, stroke or ‘mini-stroke’, or if you have experienced strange body movements with another medicine.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
  • Your doctor may do a heart test (ECG) before you start and while you are taking levomepromazine.

How is it given?

Levomepromazine is given as an injection into a muscle, vein or under the skin by a health professional.

Can you take other medicines?

Some medicines available without a prescription may react with levomepromazine including:

  • some antihistamines or anti-nausea medicines such as promethazine (e.g. Phenergan®), hyoscine (e.g. Scopoderm®), meclozine (e.g. Sea-legs®)

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products (e.g. St John's wort, valerian) or recreational drugs (e.g. cannabis).

What side effects might you notice?

Side EffectsRecommended action

Fever, stiffness, sweating, confusion

Feeling restless, strange or uncontrolled movements, tremor

Fast or irregular heartbeat, fainting

Symptoms of a blood clot including: sudden shortness of breath, swelling or pain in one leg


Symptoms of liver problems including: yellow skin or eyes, itching, dark urine, pale bowel motions, abdominal pain

Prolonged erection (longer than four hours)

Tell your doctor immediately

Dry mouth, blurred vision, constipation or trouble peeing (anticholinergic effects)

Drowsiness, dizziness

Weight gain, stomach upset

Changes in periods, sore or enlarged breasts, breastmilk production

Less interest in sex, impotence

Change in skin colour (blue, grey)

Pain, tenderness or redness at injection site

Tell your doctor if troublesome

If you notice any other effects, discuss them with your doctor or pharmacist.

Other information:

  • Levomepromazine can impair your ability to do tasks such as driving or using machines. Alcohol makes this worse. Discuss your risk with your health professional. (search NZTA - Are you safe to drive?)
  • Protect yourself from too much sunlight while being treated with levomepromazine. Always cover up and apply a thick layer of broad spectrum sunscreen (at least SPF 30) when outside. Do not use sunbeds.
  • Levomepromazine reduces your body’s ability to maintain a normal temperature. Be careful of becoming too cold or too hot. When exercising, drink plenty of water.
  • You have an increased risk of getting diabetes while taking levomepromazine. Discuss with your doctor.
  • Do not stop taking levomepromazine without talking to your doctor first.
  • This medicine is also known as methotrimeprazine.