Most dark spots in your 20s and 30s are marks left after breakouts or irritation, which are more common and slower to fade in deeper skin tones, or sun spots from UV; melasma is a different, hormone- and light-driven patchiness that needs a doctor's diagnosis. Daily SPF50+ is the foundation, with niacinamide, vitamin C or azelaic acid helping the look of uneven tone over 2 to 4 months.
Marks after breakouts are the most common kind. Inflammation from a pimple, eczema or irritation tells pigment cells to make more melanin, leaving a flat brown mark called post-inflammatory hyperpigmentation [1]. It can happen to anyone but is more common, darker and longer lasting in deeper skin tones; in one study of acne patients it affected about half of Asian patients [1][2]. Marks in the top layer can take months to years to fade on their own, while blue-grey marks deeper in the skin may last much longer [2].
Sun spots come from years of UV. Solar lentigines are flat, harmless brown spots on sun-exposed skin, and strict sun protection helps prevent new ones [3]. Because any new or changing spot needs a check in Australia, a spot should never be assumed to be a sun spot without a doctor looking at it [6].
Melasma is its own thing. It shows as blotchy, usually symmetrical brown patches on the cheeks, forehead or upper lip, most often in women aged 20 to 40 and in people who tan easily or have naturally brown skin [4][5]. UV and visible light drive it, pregnancy and hormonal contraception are involved in about a quarter of affected women, it runs in families, and it tends to return with summer sun [4].
Irritation can make all three worse. Over-exfoliating and stacking strong actives inflame skin, which can deepen marks, especially in deeper skin tones [2].
When to see a doctor
A spot is new (especially after 25), or is changing in size, shape or colour, has an irregular or notched edge or several colours, becomes raised, or is rough, scaly, itchy or bleeding: book a skin check with your GP [6].You have symmetrical brown patches on the cheeks, forehead or upper lip that could be melasma, especially in pregnancy or on hormonal contraception [4].Marks look blue-grey rather than brown, which can mean pigment sits deeper and responds poorly to skincare [2].Nothing has changed after three months of a consistent routine and daily SPF50+; a GP or dermatologist can discuss prescription options and procedures [1][4].Ask a pharmacist about azelaic acid 15% gel or 20% lotion, pharmacy medicines that dermatology guidelines recommend for post-inflammatory marks [13][14].For skin cancer questions, the Cancer Council Helpline is 13 11 20 [7].
Marks in the top layer of skin can take months to years to fade without help, and longer in deeper skin tones [2]. Consistent SPF50+ plus a tone-evening serum can help them look lighter over 2 to 4 months [1][14].
General information only, not medical advice.