Dexamethasone is a powerful corticosteroid doctors use to cut inflammation fast. You’ve probably heard it used for severe allergies, asthma flares, some autoimmune problems, certain cancers, and to control swelling after surgery. It works by tamping down your immune response. That’s useful when inflammation is doing more harm than good, but it’s also why we need to be careful with how it’s used.
Doctors give dexamethasone in several forms: pills, injections, topical creams, eye drops, or inhaled versions. Short courses (a few days) are common for bad allergic reactions or a sudden flare. Longer courses help control chronic conditions like severe asthma, rheumatoid arthritis, or to prevent nausea with cancer chemo. If you’re getting a single injection in hospital or a short oral taper at home, that’s very different from months of daily tablets.
Typical short-course examples: a few milligrams a day for several days to a week for severe allergy or swelling. Long-term therapy can be higher and needs close follow-up. Always follow your prescriber’s instructions—dosing varies a lot by condition and patient.
Because it lowers your immune system and changes metabolism, dexamethasone can cause side effects. Short-term effects may include trouble sleeping, mood swings, higher blood sugar, and increased appetite. On longer courses you might see weight gain, thinning skin, easy bruising, higher infection risk, bone thinning (osteoporosis), and adrenal suppression where your body makes less of its natural steroids.
If you have diabetes, watch blood sugar closely—steroids raise glucose. If you’re due for vaccines, talk to your doctor first, because live vaccines are often not safe during steroid therapy. Also tell any surgeon or dentist you’re taking steroids; you may need extra doses around procedures.
Never stop long-term dexamethasone suddenly. Stopping abruptly after weeks or months can cause withdrawal and low adrenal function. Your doctor will give a taper plan to reduce dose slowly and let your body recover.
Other drugs can interact with dexamethasone—blood thinners, some diabetes drugs, certain antibiotics and antifungals, and anti-seizure medicines. Ask your pharmacist or prescriber about interactions before starting.
Buying online? Use a licensed pharmacy, require a prescription when needed, check that the site uses secure connections (https), and read reviews. If something looks too cheap or avoids prescriptions, avoid it. When in doubt, call the pharmacy and ask to speak to a pharmacist.
Short term, dexamethasone can be a real lifesaver. Long term, it needs careful monitoring. If you notice high fevers, severe new weakness, sudden vision changes, or signs of infection while on steroids, contact your healthcare provider right away.
