Potent corticosteroid Pregnancy: Betamethasone readily crosses the placenta; prolonged or repeated use may increase the risk of intrauterine growth retardation. Should only be prescribed when benefits to mother and child outweigh the risks. May pass into breast milk; infants of mothers taking high doses for prolonged periods may have a degree of adrenal suppression.

Betamethasone

Brand names: Betnesol, Celestone, Betnovate (topical)

Betamethasone is a potent synthetic corticosteroid used for its anti-inflammatory and immunosuppressive effects across many conditions and, antenatally, to promote fetal lung maturation.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Short-term treatment: 2-3 mg daily for the first few days, then reducing the daily dose by 250 or 500 mcg (0.25 or 0.5 mg) every two to five days depending on response

Route: Oral (soluble tablets)

Frequency: Once daily (single morning dose preferred)

Dose depends on disease, severity and clinical response; regimens are for guidance only, divided dosage usually employed, and the lowest dose producing an acceptable result should be used. Rheumatoid arthritis: 500 mcg (0.5 mg) to 2 mg daily; lowest effective dose for maintenance. Most other conditions: 1.5 to 5 mg daily for one to three weeks, then reducing to the minimum effective dosage; larger doses may be needed for mixed connective tissue diseases and ulcerative colitis. Undesirable effects minimised by lowest effective dose, single morning dose, or alternate-day dosing. Withdrawal should not be abrupt after more than physiological doses (approximately 1 mg betamethasone or equivalent) for greater than 3 weeks. Paediatric population: a proportion of the adult dose may be used (e.g. 75% at 12 years, 50% at 7 years and 25% at 1 year) with due weight to clinical factors.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or any excipient
Systemic infections, unless specific anti-infective therapy is employed

Side effects

Suppression of the HPA axis; growth suppression in infancy, childhood and adolescence; menstrual irregularity and amenorrhoea
Cushingoid facies, hirsutism, weight gain, impaired carbohydrate tolerance
A wide range of psychiatric reactions (common)
Peptic ulceration with perforation and haemorrhage, acute pancreatitis, dyspepsia
Osteoporosis, vertebral and long bone fractures, avascular osteonecrosis, proximal myopathy

Clinical monograph

How it works

It binds glucocorticoid receptors to modulate gene transcription, reducing inflammatory mediator production and suppressing immune cell activity, with minimal mineralocorticoid effect.

Prescribing in practice

Abrupt withdrawal after prolonged systemic use can precipitate adrenal insufficiency, so courses should be tapered and patients given steroid-awareness advice.
Long-term or high-dose use carries risks of hyperglycaemia, osteoporosis, infection, hypertension and mood disturbance, requiring regular review.
Antenatal betamethasone is used to accelerate fetal lung maturity in anticipated preterm birth, given to the mother.

Monitoring

With prolonged use monitor blood glucose, blood pressure, weight and bone health, and watch for signs of infection or adrenal suppression on withdrawal.

Counselling the patient

A steroid that reduces inflammation and calms overactive immune responses.
Do not stop a longer course suddenly, and carry a steroid alert card if advised.
Report signs of infection, mood changes or increased thirst and urination.

Evidence & guidelines

Betamethasone is a long-established corticosteroid, and antenatal corticosteroids to reduce neonatal respiratory complications are recommended by NICE for anticipated preterm birth.

Reference: RCOG GTG 7; BAD; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways