Authored by Helen Allen, 23 Sep 2016

Patient is a certified member of
The Information Standard

Reviewed by:
Dr John Cox, 23 Sep 2016

Dexamethasone belongs to a class of medicines known as corticosteroids (more commonly called steroids).

Take dexamethasone with food.

If your pharmacist gives you a blue 'Steroid Treatment Card', carry this with you at all times.

If you need any medical treatment, make sure the person treating you knows you are taking dexamethasone. This is because your dose may need to be increased for a short while.
Type of medicineA corticosteroid medicine
Used forAllergic and inflammatory conditions; an inherited adrenal glands disorder called congenital adrenal hyperplasia (CAH); diagnosis of Cushing's disease; alongside chemotherapy; symptom control in palliative care; and in children, croup
Available asTablets, oral liquid medicine, and injection

Dexamethasone belongs to a group of medicines called corticosteroids. It is sometimes referred to simply as an oral steroid. Corticosteroids are produced naturally in your body. They help to keep you healthy. By boosting your body with extra corticosteroid, it can help treat conditions involving inflammation.

Oral steroids are used to treat a wide variety of conditions. Some examples include inflammatory bowel diseases (for example, Crohn's disease, ulcerative colitis), autoimmune diseases (for example, systemic lupus erythematosus (SLE), sarcoidosis), joint and muscle diseases (for example, rheumatoid arthritis), and allergies. Dexamethasone is also used in the treatment of some cancers and in people receiving palliative care. In children, it is prescribed to treat a breathing condition called croup.

Dexamethasone is also used to diagnose Cushing's disease (an adrenal gland disorder), and is prescribed as a treatment for people who have a disorder called congenital adrenal hyperplasia (CAH).

Some medicines are not suitable for people with certain conditions, and sometimes a medicine can only be used if extra care is taken. For these reasons, before you start taking dexamethasone it is important that your doctor knows:

  • If you have high blood pressure.
  • If you have had a heart attack, or if you have any other heart problems.
  • If you have any problems with the way your liver works, or if you have any problems with the way your kidneys work.
  • If you (or a close family member) have either sugar diabetes or an eye condition called glaucoma.
  • If you have any of the following conditions: an underactive thyroid, 'thinning' of the bones (osteoporosis), epilepsy, a condition causing muscle weakness (called myasthenia gravis), a stomach ulcer, or a bowel disorder.
  • If you have ever had a mental health problem.
  • If you are pregnant or breast-feeding. (Oral steroids like dexamethasone can be taken while you are expecting or breast-feeding; however, it is important that your doctor knows about the baby.)
  • If you have any kind of infection at the moment, or if you have ever had tuberculosis (TB).
  • If you have ever had an unwanted blood clot in an artery or a vein.
  • If you have recently had, or are about to have, any vaccinations.
  • If you are taking or using any other medicines. This includes any medicines which are available to buy without a prescription, as well as herbal and complementary medicines.
  • If you have ever had an allergic reaction to a medicine, or if you have ever developed muscle pain after taking a steroid medicine.
  • Before starting the treatment, read the manufacturer's printed information leaflet from inside the pack and any additional information you are given by your doctor. These will give you more information about dexamethasone and will also provide you with a full list of side-effects which you could experience from taking it.
  • Your doctor or pharmacist will tell you how much to take, and when to take your doses. Depending upon the reason why you are taking dexamethasone, you will be prescribed either a single dose, or a course of treatment. If you are prescribed a single dose, your doctor will tell you at what time to take the medicine. If you are prescribed a course of treatment, it is usual to take the doses once a day, straight after breakfast. However, if you are taking dexamethasone for CAH or as a test for Cushing's syndrome, you will be advised to take your doses at bedtime.
  • Take dexamethasone with something to eat. Swallow the tablet with a drink of water.
  • If you forget to take a dose at your usual time, take it as soon as you remember (with something to eat). If you do not remember until the following day, leave out the missed dose. Do not take two doses together to make up for a forgotten dose.
  • Continue to take dexamethasone until your doctor tells you to stop. Once you have been taking dexamethasone for more than three weeks, stopping taking it suddenly can cause problems, so your doctor will want to reduce your dose gradually over a period of time if/when this becomes necessary.
  • If your course of treatment is due to last more than three weeks, you will be given a 'Steroid Treatment Card' which says that you are on steroids and contains some important advice for you. It is important that you read this card and carry it with you at all times. It also contains details about your dose, how long you have been taking dexamethasone for, and who prescribed it for you. Please make sure that this information is kept up to date. If you are having an operation or dental treatment or any treatment for an injury, tell the person carrying out the treatment that you are taking dexamethasone and show them your treatment card. This is because your dose may need adjusting.
  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. Your doctor will want you to have tests from time to time to make sure you remain free from some of the unwanted side-effects of treatment.
  • Dexamethasone can suppress your immune system, so it is important if you become ill that you make an appointment to see your doctor straightaway. Also, if you come into contact with anyone who has measles, shingles or chickenpox (or anyone who suspects they might have them), you must see your doctor as soon as possible.
  • Some vaccines are not suitable for you while you are being treated with dexamethasone. If you need any immunisations, make sure you mention that you are taking an oral steroid.
  • If you buy any medicines, check with your pharmacist that they are suitable to take with dexamethasone.

Along with its useful effects, dexamethasone can cause unwanted side-effects which your doctor will discuss with you. The benefits of taking an oral steroid usually outweigh the side-effects; however, they can sometimes be troublesome. The table below contains some of the most common ones associated with dexamethasone. The best place to find a full list of the side-effects which can be associated with your medicine, is from the manufacturer's printed information leaflet supplied with the medicine. Alternatively, you can find an example of a manufacturer's information leaflet in the reference section below.

Although not everyone experiences side-effects, and some will improve as your body adjusts to the new medicine, speak with your doctor or pharmacist if you become concerned about any of the following:

Common dexamethasone side-effects What can I do if I experience this?
Tummy (abdominal) pain, indigestion, feeling sickStick to simple foods. If you are sick and there is blood present, you must speak with your doctor straightaway
Muscle weakness or feeling tiredDo not drive and do not use tools or machines while affected
Mood or behavioural changes, especially at the beginning of treatmentIf you become confused, irritable or start having worrying thoughts about harming yourself, speak with your doctor straightaway
Difficulties sleeping, headache, increased weight, and irregular periods in womenIf any of these become troublesome, speak with your doctor
Increased risk of getting an infectionIf you become ill, make an appointment to see your doctor straightaway
Long-term treatment with dexamethasone may cause other unwanted effectsIf you have any symptoms which are causing you concern, you should arrange to see your doctor for advice

For more information about side-effects which are possible when dexamethasone is taken long-term, see the separate leaflet called Oral Steroids.

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Further reading and references

  • Manufacturer's PIL, Dexamethasone Tablets; Aspen, The electronic Medicines Compendium. Dated July 2016.

  • British National Formulary; 71st Edition (March-September 2016) British Medical Association and Royal Pharmaceutical Society of Great Britain, London

I have very low cortisol, and I'm waiting for further tests. I suspect my deficiency is caused by a medication, but it might be autoimmune. I'm just speculating. What I really want to know, is, is...

Krazy Kitten
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