Idiopathic Guttate Hypomelanosis – Specialist Diagnosis of White Skin Spots in London

What is idiopathic guttate hypomelanosis?

Idiopathic guttate hypomelanosis (IGH) is a benign skin condition where multiple small, round white spots develop on areas exposed to the sun. The exact cause is unknown, but chronic sun damage and ageing of melanocytes are believed to play a role. While harmless, IGH is often a cosmetic concern.

Causes and development

IGH develops gradually, most often in middle-aged or older adults. Long-term sun exposure accelerates pigment cell changes, leading to areas of reduced melanin. Genetics and skin type may also influence susceptibility.

Symptoms and appearance

• White macules, usually 2–6 mm in diameter.
• Round or oval, with smooth surface.
• Appear most often on arms, shins, face, and chest.
• Asymptomatic — no itching, pain, or scaling.
• Lesions increase in number with age.

Diagnosis and tests

Diagnosis is clinical, based on the appearance and distribution of spots. Dermoscopy shows reduced pigmentation without inflammation. It is important to distinguish IGH from conditions like vitiligo, pityriasis alba, or fungal infections.

Treatment options and management

Topical treatments

Retinoid creams and mild corticosteroids may stimulate pigment production and smooth skin appearance.

Procedural options

Treatments like cryotherapy, dermabrasion, chemical peels, and fractional laser therapy can help reduce visibility of lesions and improve skin tone.

Sun protection

Daily broad-spectrum sunscreen is essential to prevent new lesions and protect against further sun damage.

When urgent review is needed

If white patches spread rapidly, involve mucous membranes, or have associated symptoms, a dermatologist should assess to rule out vitiligo or systemic causes.

Why choose Skinhorizon for IGH?

• Specialist diagnosis to confirm benign IGH and rule out other pigment conditions.
• Access to advanced treatments like fractional lasers and chemical peels in London.
• Personalised, consultant-led care under CQC standards for safe and effective management.

Your first visit — what to expect

1. History: Onset, sun exposure, family history, and skin type.
2. Examination: Dermoscopic and clinical assessment of white spots.
3. Discussion: Explanation of benign nature and treatment options.
4. Treatment plan: Tailored combination of topical or procedural treatments and strict sun protection advice.
5. Follow-up: Monitoring cosmetic outcomes and preventing recurrence.

Reviewed by: Dr Mohammad Ghazavi, Consultant Dermatologist
Skinhorizon Clinic, 4 Clarendon Terrace, Maida Vale, London W9 1BZ
Last reviewed: 21 August 2025