NZ Formulary



What does it do?

Dexamethasone is a steroid medicine used to treat and prevent a variety of conditions that involve inflammation. It is also used to treat and prevent severe nausea and vomiting.

How should you take it?

Take dexamethasone regularly as directed, with food and a glass of water.
Measure the liquid carefully with an oral syringe or measuring spoon.

What if you forget a dose?

Take the missed dose as soon as possible. If it is close to the time for your next dose, skip the missed dose and carry on as normal. Do not take two doses at the same time.

Can you take other medicines?

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

  • anti-inflammatories, such as diclofenac (e.g. Voltaren®), ibuprofen (e.g. Nurofen®), or aspirin (e.g. Disprin®, in doses used for pain relief). These can also be found in some cold and flu medicines (e.g. Nurofen Cold and Flu®).

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products or recreational drugs.

What side effects might you notice?

Side EffectsRecommended action

Changes in vision

Peeing more often, feeling thirsty

Muscle or bone aches and pains

Tell your doctor

Mood changes, restlessness, trouble sleeping

Weight gain, swollen feet or legs

Skin thinning, acne

Tell your doctor if troublesome

Stomach upset

Take with food and tell your doctor if symptoms persist

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

Other information:

  • Long term use of steroids may be associated with a range of side effects such as: round face, change in body shape, change in hair growth, thinning of the bones, increased blood pressure and diabetes.
  • If you take dexamethasone for a long time, infections may be worse or more common. Contact your doctor if you become unwell or come into contact with someone who has a contagious illness such as chicken pox or measles.
  • If you take dexamethasone in large doses or for a long time, it is dangerous to stop taking it suddenly. Your doctor may reduce the dose gradually when it is time to stop.
  • Dexamethasone affects your immune system. Before you start and while you are using it, check with your doctor what vaccines you might need. You should not have a live vaccine while using it.
  • Tell your doctor if you have stomach, heart, kidney or liver problems, high blood pressure, diabetes, glaucoma or osteoporosis (weak bones), a mood disorder, or if you have ever had a seizure.
  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
  • It is important to tell anyone who gives you medical or dental treatment that you are taking dexamethasone.
  • Dexamethasone liquid expires 7 days after you first open the bottle. If you have any liquid leftover after 7 days, take it back to your pharmacy.