Can hydroquinone cause exogenous ochronosis?

Exogenous ochronosis is a pigmentary reaction in treated skin. It often affects areas where a lightening product has been applied, such as the cheeks, forehead, or around the mouth. The colour may look grey, blue-grey, brown, or speckled, and the skin can develop small darker bumps. It may be confused with melasma or post-inflammatory pigmentation. The risk is influenced by how the product is used, how long it is used, and individual skin response; a darkening reaction is not proof of ochronosis by itself.

Stop using hydroquinone and arrange a dermatology review if treated skin becomes progressively blue-grey, unusually dark, irritated, or develops bumps. Keep the product container or a clear photograph of its ingredients, and tell the clinician how often and where it was applied. Avoid adding bleaching agents, exfoliating acids, or steroid mixtures without advice. Gentle cleansing, moisturising, and broad-spectrum sun protection can reduce irritation and pigment contrast while the diagnosis is assessed.

Seek prompt care for rapid spreading discolouration, marked burning, swelling, blistering, or open skin. Obtain urgent help for facial swelling, wheezing, or widespread hives after applying a product. A clinician should also review pigmentation that persists after stopping treatment, because several conditions can resemble ochronosis and may require different management.

Ask whether the colour and texture fit exogenous ochronosis or another pigment disorder, whether dermoscopy or biopsy is appropriate, and which treatments are safe for your skin tone. Discuss a replacement plan for the original pigmentation concern and how to monitor change without irritating the area.