Oral retinoids (isotretinoin / acitretin)
also: isotretinoin · Roaccutane · acitretin · alitretinoin
Overview
Powerful systemic vitamin-A derivatives for severe acne (isotretinoin) and psoriasis (acitretin) — highly teratogenic, specialist-initiated, under a Pregnancy Prevention Programme.
Mechanism
Isotretinoin (13-cis-retinoic acid) shrinks sebaceous glands and ↓sebum, normalises follicular keratinisation, is anti-inflammatory and reduces C. acnes — acting via nuclear retinoic-acid receptors. Acitretin normalises epidermal proliferation/differentiation in psoriasis.
Indications
- Severe / nodulocystic / scarring acne unresponsive to standard therapy (isotretinoin)
- Severe psoriasis (acitretin)
- Chronic severe hand eczema (alitretinoin)
The agents
fat-soluble; ~16–24 wk course
Contraception 1 month before/during/1 month after.
Avoid pregnancy for 3 YEARS after stopping (long retention).
Adverse effects
Severe — Pregnancy Prevention Programme; ideally 2 contraceptive methods; monthly pregnancy tests.
Baseline + on-treatment lipids/LFTs.
MHRA Oct 2023 — assess at baseline and monitor; counsel patient + family.
Do NOT co-prescribe with tetracyclines (additive risk).
Cautions & contraindications
Severe teratogen — absolute.
Intracranial hypertension.
MHRA 2023 — needs agreement of two independent prescribers that no other effective option exists.
Interactions
- Tetracyclines (IIH)
- Vitamin A supplements (additive toxicity)
- Alcohol + acitretin → re-esterification to etretinate (prolongs teratogenic window)
Monitoring & kinetics
Pregnancy Prevention Programme: monthly pregnancy tests + contraception,Baseline + periodic lipids & LFTs,Mental health + sexual function assessment (MHRA 2023)
Oral with food (fat-soluble). Specialist (dermatology) only.
Source: MHRA 2023 — Isotretinoin safety measures · BNF — Retinoids · NICE NG198 — Acne