Dexamethasone

What it is

Dexamethasone is a corticosteroid, prescription-only, and one of the more potent and longer-acting members of the class. Like other steroids it acts on receptors inside cells to damp down inflammation and immune signalling. It is used in autoimmune inflammation and in allergic conditions.

Used for

• Autoimmune inflammation
• Allergy

What to know while taking it

It is taken with food and in the morning, which reduces stomach upset and fits the body's own cortisol cycle. It raises blood glucose and depletes calcium with continued use, so glucose is the value usually followed, and bone health matters over longer courses. Its immune-suppressing effect also blunts the usual signs of infection, so an illness can be further along than it feels.

When to see a doctor

Signs of infection such as fever or a wound that will not settle, or persistent thirst, frequent urination and blurred vision suggesting high blood sugar, are reasons to see a doctor. Stopping abruptly is not safe; the course is tapered under medical direction.

Worth knowing

• Do not stop abruptly
• Raises blood glucose
• Raises infection risk

Markers to watch

• Glucose
• Potassium

Nutrients affected

• calcium — depleted by (Calcium, ionized, Calcium, total, Ferritin)