Hormonal pigmentation, an unlabelled whitening cream and a wedding in six weeks
Mrs Petrou, 34, is breastfeeding a 4-month-old and is a bridesmaid in six weeks. She has symmetrical slate-grey-brown patches on both cheeks, the upper lip and the forehead that appeared eight months ago after she started a combined oral contraceptive. For three months she has used an unlabelled "whitening" cream bought online, which stings on application. She wants "the strongest laser" before the wedding. Assessment: Fitzpatrick III, a mixed epidermal and dermal pattern under Wood's lamp, mild telangiectasia, no atrophy but slight mottling over the malar areas, no patch test ever performed, a light tan from a beach holiday five days ago, and no sunscreen use. She had post-inflammatory marks after teenage acne.
1. What does your assessment tell you, and what else must you ask before proposing anything?
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The history - onset after starting a combined oral contraceptive, symmetrical distribution, slate-grey tone, mixed Wood's lamp pattern - fits melasma with a hormonal and ultraviolet driver. The mixed pattern means the dermal component will respond slowly and incompletely, which is central to managing expectations.
The unlabelled cream is the bigger concern. Stinging, mottling and three months of an unknown product raise the possibility of an unregulated corticosteroid, hydroquinone or mercury-containing preparation, with risks of steroid-induced rosacea, atrophy, rebound pigmentation and exogenous ochronosis. I record the exact product name, batch and duration, and advise stopping it immediately.
Additional questions: other photosensitising medication, thyroid disease, family history of melasma, current skincare actives, prior laser or peel reactions, and whether she has discussed the contraceptive with her doctor. Fitzpatrick III–IV plus a recent tan plus a six-week deadline means post-inflammatory hyperpigmentation risk is high.
Breastfeeding is a hard constraint. Oral tranexamic acid is avoided, hydroquinone is not appropriate, and energy-based devices are deferred. She is not a candidate for "the strongest laser" today regardless of her wishes - the correct clinical answer is no, with a reason.
2. Build a realistic six-week plan and explain how you would gain informed consent for it.
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Plan, worked backwards from the wedding:
- Today: stop the unlabelled cream; start a bland barrier routine; tinted broad-spectrum SPF 50 every morning, reapplied every two hours outdoors, plus a wide-brimmed hat. Sun protection is the single most effective intervention and is compatible with breastfeeding.
- Week 1: 48-hour patch test behind the ear for azelaic acid 15–20%, which is considered compatible with breastfeeding and addresses both pigmentation and the mild vascular component. Add niacinamide and a stabilised vitamin C if tolerated; avoid essential oils and fragranced products.
- Weeks 2–6: gentle monthly superficial exfoliation only if the tan has faded and no irritation is present. No medium-depth peels or lasers before the wedding: PIH typically appears two to four weeks after injury, i.e. exactly on the wedding photographs.
- After the wedding and after breastfeeding ends: reassess for tranexamic acid or a carefully selected laser with priming.
Consent discussion: state the diagnosis in plain terms, that melasma is chronic and controllable rather than curable, that the dermal component limits clearance, and that no result is guaranteed by a date. Explain PIH risk with her skin type, the breastfeeding limits, the alternatives including doing nothing, and her right to stop. Document her questions and her agreement in writing, including the fact that she was offered and declined a laser.