Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Topical Retinoid — Acne / Photoaging Pregnancy: US label (the dedicated pregnancy section was cut off at the source-fetch limit; the full statement was retrieved in the Warnings/Precautions text): oral tretinoin has been shown to be teratogenic in rats, mice, hamsters and subhuman primates; topical tretinoin in animal teratogenicity tests has generated equivocal results, with fetotoxicity at 0.5 mg/kg/day in rabbits (8 times the maximum human systemic dose adjusted for total body surface area). Thirty human cases of temporally associated congenital malformations have been reported during two decades of clinical use; no definite pattern or causal association has been established, but five describe holoprosencephaly. There are no adequate and well-controlled studies in pregnant women. Tretinoin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Nursing mothers: it is not known whether the drug is excreted in human milk; caution should be exercised when administered to a nursing woman.

Tretinoin (Topical)

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

A topical retinoid (all-trans retinoic acid) used in the treatment of acne vulgaris, particularly comedonal acne, and applied to the skin as a cream or gel.

Adult dose

Dose: Acne vulgaris (tretinoin cream 0.025%): apply once a day, before retiring, to the skin where acne lesions appear, using enough to cover the entire affected area lightly.
Route: Topical, to the skin where acne lesions appear. Keep away from the eyes, the mouth, angles of the nose, and mucous membranes.
Frequency: Once a day, before retiring.
SCOPE: the pinned US label is tretinoin CREAM 0.025% and is indicated only for acne vulgaris; it states that the safety and efficacy of long-term use in other disorders have not been established, so no photoageing regimen is written. The dosage section itself does not state a concentration - the 0.025% strength is from the label's How Supplied section. If therapy has to be temporarily discontinued or the frequency reduced, it may be resumed or the frequency increased once the patient is able to tolerate treatment; alteration of vehicle, drug concentration or dose frequency should be closely monitored by careful observation of clinical response and skin tolerance. Application may cause a transitory feeling of warmth or slight stinging. During the early weeks an apparent exacerbation of inflammatory lesions may occur and should not be considered a reason to discontinue therapy. Therapeutic results should be noticed after two to three weeks, but more than six weeks of therapy may be required before definite beneficial effects are seen. Once lesions have responded satisfactorily, it may be possible to maintain the improvement with less frequent applications, or other dosage forms (no frequency is printed). The area to be treated should be cleansed thoroughly before the medication is applied; cosmetics may be used. Safety and effectiveness in patients below the age of 12 have not been established. No UK SPC for topical tretinoin is listed on eMC — this dose is from US prescribing information (Tretinoin cream USP 0.025%, Redpharm Drug) and must be verified against UK practice.

Dose adjustments

Renal

No renal dosing statement in the retrieved label sections (topical use).

Hepatic

No hepatic dosing statement in the retrieved label sections (topical use).

Dose independently re-sourced from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Use should be discontinued if hypersensitivity to any of the ingredients is noted

Side effects

  • Transitory feeling of warmth or slight stinging on application
  • Skin of certain sensitive individuals may become excessively red, oedematous, blistered or crusted - the medication should be discontinued until skin integrity is restored, or adjusted to a level the patient can tolerate
  • Topical use may induce severe local erythema and peeling at the site of application; severe irritation on eczematous skin
  • Temporary hyper- or hypopigmentation with repeated application
  • Heightened susceptibility to sunlight while under treatment
  • Apparent exacerbation of inflammatory lesions during the early weeks of therapy
  • True contact allergy to topical tretinoin is rarely encountered; all adverse effects reported to date have been reversible on discontinuing therapy

Interactions

  • Concomitant topical medication, medicated or abrasive soaps and cleansers, soaps and cosmetics with a strong drying effect, and products with high concentrations of alcohol, astringents, spices or lime - use with caution
  • Preparations containing sulfur, resorcinol or salicylic acid - particular caution; it is advisable to 'rest' the patient's skin until the effects of such preparations subside before starting tretinoin

Monitoring

  • Clinical therapeutic response and skin tolerance, particularly if the vehicle, drug concentration or frequency is altered
  • Minimise exposure to sunlight, including sunlamps; patients with sunburn should not use the product until fully recovered; use sunscreen and protective clothing over treated areas when exposure cannot be avoided
  • Weather extremes such as wind or cold may also be irritating
  • Signs of sensitivity or chemical irritation - discontinue use if a reaction suggesting sensitivity or chemical irritation occurs; use the medication less frequently, discontinue temporarily or discontinue altogether if irritation warrants
  • Eczematous skin - use with utmost caution

Clinical monograph

How it works

Tretinoin binds nuclear retinoic acid receptors to normalise follicular keratinocyte differentiation and reduce abnormal cohesion of corneocytes, preventing microcomedone formation and promoting expulsion of existing comedones.

Prescribing in practice

  • Topical retinoids are contraindicated in pregnancy and should be avoided in women planning pregnancy, with effective contraception advised during use.
  • It commonly causes skin irritation, dryness, erythema and peeling, and increases photosensitivity, so daytime sun protection and avoidance of UV/sunbeds are important.
  • An initial apparent worsening of acne can occur before improvement, and concurrent use of harsh or abrasive skin products should be avoided.

Monitoring

No laboratory monitoring is required; review tolerability and acne response, adjusting frequency of application if irritation is excessive.

Counselling the patient

  • Apply a thin amount to clean, dry skin at night and use a daytime sunscreen.
  • Expect some dryness, redness and peeling initially; reduce frequency if too irritating and allow several weeks for benefit.
  • Do not use if pregnant or trying to conceive.

Evidence & guidelines

Topical retinoids such as tretinoin are recommended by NICE as a core component of topical acne treatment, often combined with benzoyl peroxide or a topical antibiotic.

Reference: BAD Acne Guidelines 2020; Kligman et al. (1986) Retin-A photoaging; NICE NG198 (Acne); 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).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways