Skip to Content

Dexamethasone: 7 things you should know

Medically reviewed by Carmen Fookes, BPharm. Last updated on June 9, 2020.

1. How it works

  • Dexamethasone may be used in the treatment of conditions characterized by inflammation. Dexamethasone helps to reduce inflammation and calms down an overactive immune system.
  • Dexamethasone works by mimicking the effect of cortisol, a hormone released by the adrenal glands (which are located on top of the kidneys) that controls metabolism and stress.
  • Dexamethasone belongs to the class of medicines known as corticosteroids. It is specifically a glucocorticoid.

2. Upsides

  • May be used to help control inflammation associated with a wide range of conditions, such as skin diseases, endocrine disorders, ulcerative colitis, multiple sclerosis, blood disorders, nerve disorders, eye disease, renal disease, respiratory disease, rheumatic disease, and in palliative care.
  • Usually only prescribed for short-term use; however, in certain instances, dexamethasone may be prescribed for longer periods of time.
  • Dexamethasone acts similarly to prednisolone but has more potent anti-inflammatory, hormonal, and metabolic effects.
  • When given at the same dosage, dexamethasone is less likely than hydrocortisone to cause fluid retention.
  • Generic dexamethasone is available.

3. Downsides

If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:

  • Mood effects such as agitation, anxiety, and irritability; blurred vision; a change in heart rate; swelling of the limbs (sodium and water retention); increased appetite and weight gain; and concentration difficulties are the most common side effects.
  • Indigestion, facial hair growth (especially in women), high blood pressure, slow skin healing and skin thinning, osteoporosis (brittle bones), low potassium levels, and problems with blood glucose control may also occur.Rarely, severe allergic reactions have been reported.
  • Should not be used in people with systemic fungal infections or with viral infections. Dexamethasone may also increase the risk of infection and its anti-inflammatory action can mask signs of infection.
  • May not be suitable for people with certain medical conditions such as heart failure, diabetes, osteoporosis, tuberculosis, cushingoid syndrome, and peptic ulcers.
  • Overdosage may cause sodium retention, fluid retention, potassium loss, and weight gain.
  • Should not be stopped suddenly if dexamethasone has been used long-term. Reduce dosage gradually over several weeks or months to allow the adrenal glands to return to their normal patterns of secretion. Too rapid a withdrawal of dexamethasone may cause symptoms such as bone and muscle pain, fatigue, weight loss, nausea, and vomiting.
  • Alcohol use should be limited or avoided while taking dexamethasone to help prevent stomach ulcers.
  • The administration of "live vaccines" needs to be delayed for several months after dexamethasone treatment has stopped.
  • May interact with a number of other drugs including aspirin, digoxin, NSAIDs, hormonal contraceptives, other drugs metabolized by CYP 3A4, and warfarin. Dexamethasone may cause low blood potassium levels which may affect how some heart medications work.

Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects

4. Bottom Line

  • Dexamethasone reduces inflammation and calms down an overactive immune system and is significantly more potent than prednisolone. Long-term use can adversely affect the way the immune system reacts.

5. Tips

  • Take exactly as directed, do not increase or decrease the dosage of dexamethasone unless directed by your doctor. Dosage requirements for dexamethasone are variable and must be individualized based on the disease and patient response.
  • Limit or avoid alcohol use while taking dexamethasone to help prevent stomach ulcers.
  • If you are taking Intensol, an oral solution of dexamethasone, this needs to be mixed with liquid or semi-solid food such applesauce or puddings. Consume the entire amount of the stored product immediately, do not save for future use.
  • Seek medical advice as soon as possible if you develop a fever or any other signs of infection while taking dexamethasone. Also, talk to your doctor if you notice any changes with your mood or any other worrying side effects.
  • Wear a medical alert bracelet that states you are taking dexamethasone.
  • Try to avoid exposing yourself to people with an active viral infection such as chickenpox or measles. Seek medical advice urgently if you think you have been exposed inadvertently.
  • Do not stop dexamethasone suddenly if used long-term. Your doctor will advise you how to reduce the dosage of dexamethasone gradually over several weeks or months to allow the adrenal glands to return to their normal patterns of secretion. Too rapid a withdrawal of dexamethasone may cause symptoms such as bone and muscle pain, fatigue, weight loss, nausea, and vomiting.
  • Delay the administration of "live vaccines" for several months after dexamethasone treatment has stopped.
  • Make sure you inform your dentist or other health professionals that you are taking dexamethasone.

6. Response and Effectiveness

  • Peak effects of dexamethasone are reached within 10 to 30 minutes of administration; however, it may take a couple of days before any inflammation is well controlled.

7. Interactions

Medicines that interact with dexamethasone may either decrease its effect, affect how long it works for, increase side effects, or have less of an effect when taken with dexamethasone. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.

Common medications that may interact with dexamethasone include:

  • antacids
  • antibiotics, such as clarithromycin, erythromycin, rifabutin, rifampin, or troleandomycin
  • anticholinesterases, such as neostigmine, or pyridostigmine
  • anticoagulants (blood thinners) such as apixaban, dabigatran, fondaparinux, heparin, or warfarin
  • antidepressants, such as desipramine, fluoxetine, sertraline, or St. John's Wort
  • antifungal medications, such as itraconazole, ketoconazole, or voriconazole
  • antinausea medications, such as aprepitant
  • aspirin
  • clozapine
  • cobicistat
  • CYP 3A4 inducers, such as phenobarbital, phenytoin, rifampicin, St. John's Wort or glucocorticoids
  • CYP 3A4 inhibitors, such as clarithromycin, erythromycin, diltiazem, itraconazole, ketoconazole, ritonavir, verapamil, goldenseal or grapefruit
  • echinacea
  • epilepsy medications, such as carbamazepine, oxcarbazepine, phenobarbital, phenytoin, or primidone
  • estrogen-containing hormonal contraceptives (includes birth control pills, patches, rings, implants, and injections)
  • heart medications, such as amiodarone, diltiazem, or verapamil
  • HIV medications (eg, atazanavir, delavirdine, efavirenz, indinavir, etravirine, ritonavir, nevirapine, saquinavir, or tipranavir)
  • immunosuppressants, such a cyclosporine
  • nonsteroidal anti-inflammatories (NSAIDs), such as celecoxib, diclofenac, etodolac, ibuprofen, ketorolac, meloxicam, nabumetone, or naproxen
  • other corticosteroids, such as prednisone
  • potassium-depleting agents, such as amphotericin B Injection and diuretics (eg, furosemide, hydrochlorothiazide)
  • some asthma medications, such as zafirlukast
  • vaccines (may inhibit the immune response)
  • others, such as aminoglutethimide, bupropion, cholestyramine, cyclosporine, digoxin, isoniazid, quetiapine, or thalidomide.

Dexamethasone may increase blood glucose concentrations in people with diabetes and dosage adjustments of antidiabetic agents (eg, insulin, glyburide) may be required. Use with fluoroquinolone antibiotics (such as ciprofloxacin, levofloxacin) may increase the risk of tendon rupture with fluoroquinolones.

In addition, alcohol can increase the likelihood of gastrointestinal side effects with dexamethasone, and possibly liver and kidney damage. Dexamethasone may suppress the inflammatory response to skin tests.

Note that this list is not all-inclusive and includes only common medications that may interact with dexamethasone. You should refer to the prescribing information for dexamethasone for a complete list of interactions.


Dexamethasone [Package Insert]. Revised 01/2020.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use dexamethasone only for the indication prescribed.

Copyright 1996-2021 Revision date: June 9, 2020.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.