METADEXAN Tablet — Dexamethasone 0.5mg by Beximco Pharmaceuticals

METADEXAN Tablet — Dexamethasone 0.5mg | Beximco Pharmaceuticals

Overview

METADEXAN contains Dexamethasone — the most potent commonly available synthetic glucocorticoid corticosteroid. Dexamethasone has approximately 25 times the anti-inflammatory potency of hydrocortisone and 6 times that of prednisolone, with minimal mineralocorticoid activity (causing less sodium and water retention than older steroids). It is used for a wide range of inflammatory, allergic, autoimmune, and haematological conditions, as well as for cerebral oedema, severe COVID-19 (RECOVERY trial evidence), and as a component of cancer chemotherapy regimens. Dexamethasone has critical implications for diabetic patients — it is one of the most potent drivers of steroid-induced hyperglycaemia.

Mechanism of Action

Dexamethasone binds glucocorticoid receptors in virtually all body cells, translocating to the nucleus and altering transcription of hundreds of genes. Anti-inflammatory effects: suppresses COX-2, phospholipase A2, and pro-inflammatory cytokines (IL-1, IL-6, TNF-α). Immunosuppressive effects: reduces lymphocyte and eosinophil counts, suppresses T-cell activation. Metabolic effects: promotes gluconeogenesis, increases hepatic glucose output, induces peripheral insulin resistance, and stimulates lipolysis — all mechanisms contributing to steroid-induced hyperglycaemia.

Indications

• Severe allergic reactions — anaphylaxis adjunct, angioedema
• Asthma — severe exacerbations
• Inflammatory conditions — rheumatoid arthritis, inflammatory bowel disease
• Autoimmune diseases — SLE, myasthenia gravis, pemphigus
• Cerebral oedema — vasogenic (tumour, abscess)
• Haematological — ITP, AIHA, multiple myeloma regimens
• Severe COVID-19 requiring oxygen — 6mg once daily × 10 days (RECOVERY protocol)
• Nausea and vomiting in chemotherapy (antiemetic)
• Dexamethasone suppression test — Cushing's syndrome diagnosis

Dosage (Adult)

Take oral tablets with food to reduce GI irritation. Never stop abruptly after prolonged use — taper dose gradually to prevent adrenal insufficiency.

Critical Diabetic Patient Warnings

• Steroid-induced hyperglycaemia: Dexamethasone is the most potent cause of steroid-induced hyperglycaemia of all commonly used steroids. Even a single dose can raise blood glucose by 5–10 mmol/L in diabetic patients. Monitor BGL every 2–4 hours during steroid treatment. Insulin dose adjustments are almost always required.
• Pattern of hyperglycaemia: Dexamethasone given as a morning dose typically causes afternoon and evening hyperglycaemia with less effect on fasting morning glucose. Basal insulin adjustments alone may be insufficient — prandial/correction doses must be increased.
• Masking hypoglycaemia: Steroids reduce sympathetic hypoglycaemia symptoms — patients may not feel the warning signs. Frequent BGL testing is essential.
• New-onset diabetes: Dexamethasone can unmask latent diabetes or cause new-onset steroid diabetes — especially in patients with pre-diabetes, obesity, or family history. Monitor non-diabetic patients on steroids as well.
• Metformin caution: During steroid treatment, hyperglycaemia may necessitate insulin. If the patient is very unwell or dehydrated, withhold metformin (lactic acidosis risk). Resume when stable.
• Immunosuppression: Steroids suppress immune function — monitor diabetic patients carefully for infection (particularly opportunistic fungal, bacterial, or viral).

Side Effects

Short-term: hyperglycaemia, insomnia, mood changes, increased appetite, fluid retention. Long-term: Cushing's syndrome, osteoporosis, adrenal suppression, weight gain, cataracts, glaucoma, increased infection risk, muscle wasting, skin thinning. Never stop abruptly — risk of adrenal crisis.

Contraindications

Systemic fungal infections (without antifungal cover). Active untreated tuberculosis. Live vaccine administration during immunosuppressive doses. Use with extreme caution in: diabetes, peptic ulcer, osteoporosis, psychiatric disorders, heart failure, hypertension.

Storage

Store below 25°C in a dry place. Protect from light and moisture. Keep out of reach of children.

Medical Disclaimer: Dexamethasone causes significant hyperglycaemia in diabetic patients — blood glucose monitoring and insulin dose adjustment are essential during corticosteroid treatment. Never self-prescribe corticosteroids. Prescription required. Do not stop abruptly after prolonged use.