1. Clinical Overview
A fixed-dose combination topical medication containing a potent corticosteroid (Betamethasone dipropionate) and a vitamin D3 analogue (Calcipotriol). It is a first-line treatment for moderate to severe plaque psoriasis in adults, offering synergistic anti-inflammatory, immunosuppressive, and anti-proliferative effects. It is formulated as an ointment, cream, or gel for topical application.
| Onset | Duration | Bioavailability |
|---|---|---|
| Clinical improvement in scaling and erythema is typically observed within 1-2 weeks of treatment initiation. | The therapeutic effect is maintained during the treatment period. Rebound or relapse may occur after discontinuation, typically within 4-8 weeks. | Topical bioavailability is low and variable. Systemic absorption of Calcipotriol is <1% and Betamethasone is <5% when applied to intact skin. Absorption increases significantly with application to inflamed skin, damaged skin, occlusive dressings, or large surface areas. |
2. Mechanism of Action
The combination exerts a synergistic effect on psoriasis by targeting multiple pathogenic pathways. Betamethasone provides rapid anti-inflammatory and immunosuppressive action, while Calcipotriol normalizes keratinocyte differentiation and proliferation, and has immunomodulatory effects.
3. Indications & Uses
- Treatment of stable plaque psoriasis (psoriasis vulgaris) in adults
- Moderate to severe chronic plaque psoriasis affecting up to 30% body surface area
4. Dosage & Administration
Adult Dosage: Apply a thin layer once daily to the affected areas. Maximum recommended dose is 100g per week. Initial treatment period should be limited to 4 weeks. For maintenance, intermittent use (e.g., weekends-only therapy) may be employed under medical supervision.
Administration: Apply to clean, dry skin. Gently rub in until absorbed. Wash hands after application unless hands are being treated. Do not use with occlusive dressings unless specifically advised by a physician. Avoid contact with eyes, mouth, and mucous membranes. Do not apply on broken or infected skin.
5. Side Effects
Common side effects may include:
- Local burning, itching, or stinging sensation
- Skin irritation, erythema, or dryness at application site
- Mild folliculitis
- Skin atrophy with prolonged use (especially on thin skin areas)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Other Topical Corticosteroids | Increased risk of skin atrophy, striae, and systemic corticosteroid effects. | Major |
| Thiazide Diuretics (e.g., Hydrochlorothiazide) | Increased risk of hypercalcemia due to reduced calcium excretion. | Moderate |
| Systemic Corticosteroids (e.g., Prednisolone) | Additive risk of HPA axis suppression and Cushingoid features. | Major |
| Calcium Supplements/Vitamin D | Increased risk of hypercalcemia. | Moderate |
| CYP3A4 Inhibitors (e.g., Ketoconazole, Itraconazole - topical or systemic) | May inhibit metabolism of betamethasone, increasing systemic exposure and risk of side effects. | Moderate |
7. Patient Counselling
- DO apply a thin layer once daily only to affected psoriatic plaques.
- DO wash hands before and after application.
- DO inform your doctor if you are using any other creams/ointments.
- DON'T use on face, underarms, groin, or other sensitive areas unless directed.
- DON'T use more than 100g in a week (roughly 2 standard 50g tubes).
- DON'T use with tight, occlusive dressings.
- DON'T stop other psoriasis medications without consulting your doctor.
8. Toxicology & Storage
Overdose: Topical Overdose: Signs of systemic corticosteroid excess (Cushing's syndrome: moon face, central obesity, hypertension, hyperglycemia) and/or hypercalcemia (thirst, polyuria, constipation, nausea, vomiting, confusion, fatigue). Local overdose can cause severe skin atrophy, striae, telangiectasia, and HPA axis suppression.
Storage: Store below 25°C. Do not freeze. Keep the tube tightly closed. Protect from light and moisture. Keep out of reach and sight of children. Do not use after the expiry date printed on the pack.