Examqo › Examqo library › Dermatology and venereology › Dermatologic treatments · IMLE
Topical corticosteroids
Topical corticosteroids are the basis of treatment for inflammatory skin disease; the choice is made by potency, body site, age and vehicle, and the amount is measured in "fingertip units" — this is how efficacy is achieved and side effects prevented.
Why it matters in the exam
The exam shows a baby with facial eczema and asks which potency suits (mild), an adult with palmoplantar psoriasis (very potent), a patient with redness and papules around the mouth after months of a potent facial steroid (perioral dermatitis), or "tinea" with a strange look after steroid treatment (tinea incognito). The question tests the potency ladder — mild (hydrocortisone 1%), moderate, potent (betamethasone valerate, mometasone) and very potent (clobetasol propionate 0.05%) — absorption differences between sites (eyelids, face, folds and genitals absorb a lot; palms and soles absorb little), and side effects: atrophy, striae, telangiectasia, acne and rosacea, glaucoma and cataract around the eyes, and HPA-axis suppression in babies and with widespread use. Remember that "steroid phobia" in parents is a common cause of treatment failure, and that explaining the right amount and a limited duration improves adherence. One fingertip unit is about 0.5 g and covers an area of two adult palms. The vehicle matters too: ointment for dry thick skin, cream for moist areas, and lotion or foam for the scalp.
Key points
- Topical corticosteroids are the basis of treatment for inflammatory skin disease, chosen by potency, site, age and vehicle.
- Potencies range from mild (hydrocortisone 1%) to very potent (clobetasol propionate 0.05%).
- Face, eyelids, folds and babies get a mild steroid; palms and thick plaques get a very potent steroid.
- One fingertip unit is about 0.5 g and covers an area of two adult palms.
- Side effects include atrophy, striae, telangiectasia, perioral dermatitis, tinea incognito and HPA-axis suppression.
Summary table
| Potency | Example | Suitable use | Notes |
|---|---|---|---|
| Mild | Hydrocortisone 1% | Face, eyelids, folds and babies | Relatively safe for long-term use |
| Moderate | Clobetasone butyrate 0.05% | Mild body eczema, face for a short time | Step between mild and potent |
| Potent | Betamethasone valerate 0.1%, mometasone 0.1% | Eczema and psoriasis on the body and limbs | Once daily is usually enough |
| Very potent | Clobetasol propionate 0.05% | Palmoplantar psoriasis, lichen sclerosus, lichen planus, pemphigoid | Limited time; not on the face and folds except in special cases |
| Side effects | Atrophy, striae, telangiectasia, perioral dermatitis, tinea incognito | Long-term use, high potency, thin sites | Babies and widespread use — HPA-axis suppression |
In the full version for subscribers
- A simple algorithm
- Memory aid
- Exam traps
- 5 review cards
- Enough for IMLE
The full version is open to subscribers of: Dermatology and venereology, Medical licensing exam (IMLE), Family medicine, Pediatrics.
Subscriber? Read the full topic Plans and prices 25 free questions
Sources
- British National Formulary — topical corticosteroids, 2025 — Potency and fingertip units
- National Eczema Society and BAD guidance on topical steroid use, 2023 — Safe use and withdrawal
- AAD guidelines of care for the management of atopic dermatitis with topical therapies, 2023 — Topical corticosteroids
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.