Dexamethasone

What Is Dexamethasone and What Is It Used For?

Dexamethasone is a fluorinated synthetic glucocorticoid first synthesized in 1957. It has become one of the most widely prescribed corticosteroids worldwide due to its high potency, long duration of action, and minimal mineralocorticoid activity (meaning it causes very little sodium and water retention compared to other corticosteroids). It is included on the WHO Model List of Essential Medicines, underscoring its critical importance in global healthcare.

Corticosteroids like dexamethasone work by binding to intracellular glucocorticoid receptors. Once bound, the drug-receptor complex moves into the cell nucleus and modulates the transcription of numerous genes. This leads to a broad suppression of inflammatory mediators including prostaglandins, leukotrienes, and pro-inflammatory cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor alpha (TNF-α). The net effect is a powerful reduction in inflammation and immune activity.

Dexamethasone has an anti-inflammatory potency approximately 25-30 times that of hydrocortisone and 6-7 times that of prednisolone, making it suitable for conditions requiring intensive glucocorticoid therapy. Its biological half-life is 36-54 hours, which is significantly longer than most other corticosteroids, allowing for once-daily or even less frequent dosing in many indications.

Approved Indications

Dexamethasone is approved for the treatment of a broad spectrum of conditions. The specific indications may vary by country and formulation, but commonly include:

• Cerebral edema — Swelling of the brain caused by tumors (primary or metastatic), neurosurgery, or brain abscesses. Dexamethasone is often the corticosteroid of choice because it has minimal mineralocorticoid activity and does not promote additional fluid retention.
• Severe acute asthma — As part of acute exacerbation management, particularly in emergency settings or when oral prednisolone is not adequate.
• Severe skin diseases — Including pemphigus, severe eczema, and other autoimmune dermatological conditions refractory to first-line therapy.
• Autoimmune disorders — Such as systemic lupus erythematosus (SLE), autoimmune hemolytic anemia, and immune thrombocytopenic purpura (ITP).
• Rheumatoid arthritis — For acute flares and when disease-modifying antirheumatic drugs (DMARDs) are insufficient.
• Chemotherapy-induced nausea and vomiting (CINV) — Dexamethasone is a cornerstone of antiemetic regimens for both prevention and treatment of CINV, often combined with 5-HT3 receptor antagonists and NK1 receptor antagonists.
• Croup (laryngotracheobronchitis) — A single dose of dexamethasone is the standard treatment for children with moderate to severe croup, significantly reducing symptoms and the need for hospitalization.
• Allergic reactions — Including severe acute allergic reactions and anaphylaxis (as adjunctive therapy alongside epinephrine).
• COVID-19 — In adults and adolescents (aged 12 years and older, weighing at least 40 kg) with respiratory failure requiring supplemental oxygen therapy. The landmark RECOVERY trial demonstrated a significant reduction in mortality.
• Multiple myeloma — As part of combination chemotherapy regimens (e.g., with bortezomib and lenalidomide).

What Should You Know Before Taking Dexamethasone?

Dexamethasone is a powerful medication that requires careful medical supervision. Before starting treatment, your doctor needs a comprehensive understanding of your medical history and current health status. This allows them to weigh the benefits against potential risks and establish appropriate monitoring protocols throughout your treatment.

Contraindications

You should not take dexamethasone if you are allergic to dexamethasone or any of the other ingredients in the formulation. Beyond this absolute contraindication, there are several relative contraindications where the drug should be used with extreme caution or avoided unless the benefits clearly outweigh the risks:

• Systemic fungal infections (unless specific antifungal therapy is being administered concurrently)
• Active untreated tuberculosis or other serious bacterial infections without appropriate antimicrobial coverage
• Live or live-attenuated vaccines (immunosuppressive doses of corticosteroids can impair vaccine efficacy and increase the risk of vaccine-strain infection)
• Herpes simplex keratitis (eye infection) — corticosteroids can cause corneal perforation
• Active peptic ulcer disease without adequate gastroprotection

Warnings and Precautions

Discuss the following conditions with your doctor before starting dexamethasone, as they may require dose adjustment, additional monitoring, or alternative treatment:

Adrenal insufficiency: Depending on the dose and duration of treatment, adrenal suppression caused by dexamethasone may persist for months or, in exceptional cases, more than a year after discontinuation. This means your body may be unable to produce adequate cortisol during periods of physiological stress such as surgery, trauma, fever, or serious illness. Your doctor may prescribe supplemental corticosteroid coverage during these periods. Acute adrenal crisis can be minimized by gradual, planned dose tapering.

Infections: Dexamethasone can increase susceptibility to new infections and mask the signs and symptoms of existing infections, making them harder to diagnose. Latent infections, including tuberculosis and hepatitis B, may become reactivated. If you have not had chickenpox or measles and come into contact with someone who has these infections, seek medical advice immediately as corticosteroids can cause these viral infections to be more severe.

Pheochromocytoma crisis: Treatment with dexamethasone can trigger a potentially fatal pheochromocytoma crisis. Pheochromocytoma is a rare tumor of the adrenal glands. Seek immediate medical attention if you experience sudden headache, excessive sweating, palpitations, or severe high blood pressure.

Diabetes: Dexamethasone can significantly increase blood glucose levels and may worsen pre-existing diabetes or unmask latent diabetes. Blood glucose monitoring is essential, and adjustments to diabetes medications (oral agents or insulin) may be necessary.

Osteoporosis: Long-term corticosteroid use is one of the most common causes of secondary osteoporosis. Bone density monitoring should be considered, and preventive measures such as calcium and vitamin D supplementation may be recommended.

Psychiatric effects: Corticosteroids can cause a range of psychiatric effects including euphoria, insomnia, mood swings, depression, personality changes, and in severe cases, psychotic episodes. These effects can occur at any dose but are more common with higher doses. Patients with a history of psychiatric illness should be closely monitored.

Cardiovascular: Dexamethasone can cause elevated blood pressure, fluid retention, and increased risk of atherosclerosis and thrombosis with prolonged use. Patients with severe heart failure or poorly controlled hypertension require careful monitoring.

Gastrointestinal: The risk of peptic ulcer disease and gastrointestinal bleeding is increased, particularly when dexamethasone is combined with NSAIDs. High doses may mask the symptoms of gastrointestinal perforation.

Ophthalmologic effects: Long-term use increases the risk of cataracts and glaucoma. Blurred vision or other visual disturbances should be reported to your doctor immediately. Regular eye examinations are recommended during prolonged treatment.

Children and Adolescents

Dexamethasone can delay growth in children, and therefore growth should be monitored regularly during treatment. The drug should only be used in children when the benefit clearly outweighs the risk, and at the lowest effective dose for the shortest possible duration. For COVID-19 treatment, dexamethasone is approved for adolescents aged 12 years and older weighing at least 40 kg.

Elderly Patients

Older adults are generally more susceptible to the adverse effects of corticosteroids, particularly osteoporosis, diabetes, hypertension, and skin thinning. Lower starting doses and more frequent monitoring are typically recommended. The risk-benefit balance should be carefully assessed before initiating therapy in elderly patients.

Pregnancy and Breastfeeding

Dexamethasone should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. Unlike prednisolone, dexamethasone crosses the placenta efficiently — a property that is clinically exploited when accelerating fetal lung maturation in cases of threatened preterm delivery. However, prolonged use during pregnancy may increase the risk of intrauterine growth restriction and neonatal adrenal suppression.

Dexamethasone is excreted in breast milk. Your healthcare provider will advise whether to discontinue breastfeeding or discontinue the medication, taking into account the importance of the drug to the mother. If breastfeeding is continued, the infant should be monitored for signs of adrenal suppression.

Driving and Operating Machinery

Dexamethasone is not generally expected to affect the ability to drive or operate machinery. However, if you experience side effects such as blurred vision, visual disturbances, or dizziness, you should not drive or operate heavy machinery until these effects resolve. You are responsible for assessing your own fitness to perform these activities.

How Does Dexamethasone Interact with Other Drugs?

Because dexamethasone is extensively metabolized by the cytochrome P450 enzyme system (primarily CYP3A4) and affects numerous physiological processes, it interacts with a wide variety of medications. Understanding these interactions is crucial for safe and effective therapy.

Major Interactions

Additional Interactions

The following drug interactions, while generally less severe, are clinically relevant and may require dose adjustments or enhanced monitoring:

• Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — Increased risk of tendon damage, tendinitis, and tendon rupture. This risk is further elevated in patients over 60, those with kidney transplants, or those taking other drugs known to affect tendons.
• Oral contraceptives (estrogens) — May increase the plasma concentration of dexamethasone by reducing its hepatic clearance, potentially enhancing both therapeutic and adverse effects.
• Antimalarials (chloroquine, hydroxychloroquine, mefloquine) — Increased risk of myopathy (muscle disease) and cardiomyopathy (heart muscle disease) when used concomitantly.
• Muscle relaxants (rocuronium, vecuronium) — Dexamethasone may alter the duration of neuromuscular blockade.
• Growth hormone (somatotropin) — The growth-promoting effect of somatotropin may be reduced.
• Vaccines (live) — Immunosuppressive doses of dexamethasone may diminish the immune response to vaccines. Live vaccines should be avoided; inactivated vaccines may have reduced efficacy.
• Antacids (aluminum hydroxide, magnesium hydroxide) — May reduce the absorption of dexamethasone. Separate administration by at least 2 hours.

What Is the Correct Dosage of Dexamethasone?

Dexamethasone dosing varies enormously depending on the condition being treated, the severity of disease, and individual patient factors. Unlike many medications with fixed dosing schedules, corticosteroid therapy often requires careful dose titration and individualization. Your doctor will determine the optimal dose and treatment duration based on your specific clinical situation.

The general principle of corticosteroid therapy is to use the lowest effective dose for the shortest possible time. This minimizes the risk of serious adverse effects associated with prolonged corticosteroid exposure while maintaining therapeutic benefit.

Adults

Children

Pediatric dosing is generally calculated based on body weight or body surface area. Children are at particular risk of growth suppression with long-term corticosteroid use, so treatment should be limited to the minimum effective dose and duration. Regular growth monitoring is essential.

Elderly

No specific dose adjustments are mandated for elderly patients, but lower starting doses and more cautious dose escalation are generally advisable. Elderly patients are at increased risk of osteoporosis, diabetes, hypertension, cataracts, and skin fragility. Bone protection measures (calcium, vitamin D, and possibly bisphosphonates) should be considered from the outset if prolonged treatment is anticipated.

Missed Dose

If you miss a dose, take it as soon as you remember. However, if it is close to the time for your next scheduled dose, skip the missed dose and resume your normal dosing schedule. Do not take a double dose to make up for a missed one. If you are unsure, consult your pharmacist or doctor.

Overdose

There are no well-documented cases of acute dexamethasone toxicity from single overdoses. However, in case of significant overdose, the adverse effects described in this article may occur in a more severe form. If you suspect an overdose, contact your local poison control center or emergency services immediately for risk assessment and advice.

What Are the Side Effects of Dexamethasone?

Dexamethasone, like all corticosteroids, has the potential to cause significant adverse effects, although not everyone experiences them. The likelihood and severity of side effects depend primarily on the dose and duration of treatment. Short courses at moderate doses are generally well-tolerated, while prolonged high-dose therapy carries a substantially higher risk of serious complications.

The following side effects have been reported with dexamethasone use. They are categorized by frequency and body system to help you understand the relative likelihood of each adverse effect.

Blurred vision and visual disturbances: If you experience blurred vision, visual loss, or other visual changes while taking dexamethasone, contact your doctor promptly. These symptoms may indicate cataracts, glaucoma, central serous chorioretinopathy, or other ophthalmologic conditions that require evaluation.

Psychiatric effects: Corticosteroid-induced psychiatric effects can range from mild mood changes to severe psychosis. Symptoms such as suicidal thoughts, severe depression, mania, or confusion should be reported to your healthcare provider immediately. These effects are generally reversible upon dose reduction or discontinuation.

How Should You Store Dexamethasone?

Proper storage of medication is essential to maintain its effectiveness and safety. Follow these guidelines for storing dexamethasone:

• Store at room temperature (typically below 25°C / 77°F) unless otherwise directed on the packaging.
• Keep in the original packaging to protect from light and moisture.
• Keep out of the sight and reach of children.
• Do not use the medication after the expiry date stated on the label (EXP). The expiry date refers to the last day of the stated month.
• For eye drops: note the specific expiry after opening (typically 28 days) and discard any remaining solution after this period.
• Do not dispose of medications via wastewater or household waste. Ask your pharmacist about proper disposal methods to protect the environment.

What Does Dexamethasone Contain?

Dexamethasone is available in several different formulations, each containing the active ingredient in a different salt form or concentration. The specific inactive ingredients (excipients) vary between manufacturers and product forms:

• Tablets (1 mg, 4 mg): The active substance is dexamethasone. Typical excipients include lactose monohydrate, microcrystalline cellulose, magnesium stearate, and croscarmellose sodium. Specific formulations vary by manufacturer.
• High-dose tablets (40 mg — e.g., Neofordex): Used in multiple myeloma treatment protocols. Excipients include lactose, microcrystalline cellulose, magnesium stearate, and colloidal anhydrous silica.
• Oral dissolving film (e.g., Zeqmelit): Contains dexamethasone in an orodispersible film form. Excipients include hypromellose and glycerol. Available in 4 mg, 6 mg, and 8 mg strengths.
• Eye drops / suspension (e.g., Isopto-Maxidex): Contains dexamethasone as the active ingredient, typically at 0.1% (1 mg/ml). Excipients typically include benzalkonium chloride (preservative), sodium chloride, disodium edetate, polysorbate 80, and purified water.
• Intravitreal implant (OZURDEX): Contains 700 micrograms of dexamethasone in a biodegradable polymer matrix for sustained release directly into the eye. Used for macular edema and non-infectious uveitis.

If you have known allergies to specific excipients (such as lactose intolerance or sensitivity to benzalkonium chloride), always check the full ingredient list in the patient information leaflet of your specific product, or ask your pharmacist.

References

This article is based on the following peer-reviewed sources and international clinical guidelines:

1. RECOVERY Collaborative Group. Dexamethasone in Hospitalized Patients with Covid-19. N Engl J Med. 2021;384(8):693-704. doi:10.1056/NEJMoa2021436
2. World Health Organization. Corticosteroids for COVID-19: Living Guidance. WHO. 2020. WHO-2019-nCoV-Corticosteroids-2020.1
3. World Health Organization. WHO Model List of Essential Medicines — 23rd List. WHO. 2023. WHO Essential Medicines 2023
4. European Medicines Agency. Dexamethasone — Summary of Product Characteristics (SmPC). EMA. 2024. ema.europa.eu
5. National Institute for Health and Care Excellence (NICE). Corticosteroids — Glucocorticoid therapy. British National Formulary (BNF). 2025. bnf.nice.org.uk
6. Liu D, et al. A practical guide to the monitoring and management of the complications of systemic corticosteroid therapy. Allergy Asthma Clin Immunol. 2013;9(1):30. doi:10.1186/1710-1492-9-30
7. Czock D, et al. Pharmacokinetics and pharmacodynamics of systemically administered glucocorticoids. Clin Pharmacokinet. 2005;44(1):61-98. doi:10.2165/00003088-200544010-00003
8. Russell CD, et al. Clinical evidence does not support corticosteroid treatment for 2019-nCoV lung injury [updated with RECOVERY trial data]. The Lancet. 2020;395(10223):473-475.
9. Hoes JN, et al. EULAR evidence-based recommendations on the management of systemic glucocorticoid therapy in rheumatic diseases. Ann Rheum Dis. 2007;66(12):1560-1567.

Medical Editorial Team

This article has been written and medically reviewed by our editorial team of licensed physicians specializing in clinical pharmacology, endocrinology, and internal medicine. All content follows evidence-based medicine principles and adheres to international guidelines (WHO, EMA, FDA, BNF, NICE).

Published: May 9, 2025 | Last reviewed: January 2, 2026 | Evidence level: 1A (systematic reviews and RCTs)