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Topical Retinoid — Acne / Photoaging Pregnancy: CONTRAINDICATED — teratogenic; effective contraception required; all topical retinoids contraindicated in pregnancy

Tretinoin (Topical)

Brand names: Retin-A, Retrieve, Acnecide (different ingredient)

Adult dose

Dose: 0.025–0.1% cream or gel — start low (0.025%), apply a pea-sized amount
Route: Topical
Frequency: Once nightly (every other night initially to build tolerance)
Max: 0.1% once nightly
Used for acne vulgaris (mild-moderate — combined with topical antibiotic or benzoyl peroxide) and photoaging (off-label in UK — licensed for acne). Start at lowest strength, apply to entire face after washing, increase concentration gradually. Sun protection mandatory.

Paediatric dose

Dose: Apply pea-sized amount to face nightly topical/kg
Route: Topical
Frequency: Once nightly (every other night initially)
Max: 0.05% for acne in adolescents
BNFc: licensed from 12 years for acne. Start with 0.025% to minimise retinoid dermatitis.

Dose adjustments

Renal

No dose adjustment required (topical — negligible systemic absorption)

Hepatic

No dose adjustment required

Paediatric weight-based calculator

BNFc: licensed from 12 years for acne. Start with 0.025% to minimise retinoid dermatitis.

Clinical pearls

  • CONTRAINDICATED in pregnancy — teratogenic (topical retinoids absorbed systemically; pregnancy test and contraception required in women of childbearing potential on systemic therapy; topical tretinoin systemic absorption is low but contraindication maintained)
  • Initial flare: acne worsens weeks 1–4 (purging effect — comedone expulsion); warn patients not to stop treatment during this phase
  • Apply at night: photolabile — UV light degrades tretinoin; morning sun protection (SPF 30+) mandatory
  • Adapalene (0.1%) is generally better tolerated in sensitive skin — less irritating than tretinoin 0.025%; good alternative for acne
  • Benzoyl peroxide interaction: apply benzoyl peroxide in the morning, tretinoin at night — benzoyl peroxide oxidises tretinoin if applied simultaneously, reducing efficacy
  • Photoaging (UK off-label): strongest evidence for any topical product in reducing fine lines and photodamage (Kligman studies)

Contraindications

  • Pregnancy — CONTRAINDICATED (teratogenic — all topical retinoids)
  • Breastfeeding
  • Eczema or rosacea (can exacerbate)
  • Broken or sunburned skin

Side effects

  • Retinoid dermatitis (erythema, peeling, dryness — most common; resolves with continued use)
  • Photosensitivity
  • Initial acne flare (weeks 1–4)
  • Hyperpigmentation or hypopigmentation (post-inflammatory)
  • Skin thinning (long-term high concentration)

Interactions

  • Other topical retinoids — additive irritation
  • Keratolytics (salicylic acid) — additive irritation; avoid concurrent use
  • Benzoyl peroxide — inactivates tretinoin if applied simultaneously; use AM/PM split

Monitoring

  • Skin tolerability (retinoid dermatitis)
  • Acne response at 8–12 weeks
  • Sun protection compliance

Reference: BNFc; BNF 90; BNFc; BAD Acne Guidelines 2020; Kligman et al. (1986) Retin-A photoaging; NICE NG198 (Acne). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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