Exogenous ochronosis is a very controversial skin disorder due to the over-use of the skin lightening agent hydroquinone. Exogenous ochronosis is generally seen in Blacks, though reportedly seen in Hispanics, Asians, Indians, and Caucasians. Prolonged use of hydroquinone causes a clinical presentation of blue/black patches seen mostly in the sun-exposed areas of the face. A higher incidence is seen among South African women with at least 1/3 of those affected using hydroquinone products since the early 80s.
In the United States, blacks affected by exogenous ochronosis have a long history of using hydroquinone. Most use over-the-counter skin lightening products containing only 2% hydroquinone. The long-term use of this ingredient is generally the cause, studies suggest that it also may be an inherent family history.
Over-the-counter skin lightening products used in the U.S. contain only 2% hydroquinone compared to the 6% to 8% hydroquinone found in products purchased in South Africa. South Africa, with the sun, a high concentration of hydroquinone, and preparations containing ochronotic agents such as resorcinol, mercury, and phenol provides the fundamental onset of the blue-black, sometimes gray-blue discolorations of the skin.
Many times physicians misdiagnose this disorder as melasma and prescribe a regimen of 4% hydroquinone. This compounds the problem with the patient’s already long-term use of an agent that is causing the condition..
The FDA has confirmed that hydroquinone can be safely used in 2 percent concentrations.
Clients receiving a 2% hydroquinone product should be informed of the risk factors when using long-term. It should be used in the evenings on the pigmented areas only unless otherwise instructed by a licensed professional. If there is no significant reduction of a darkened area within 3 months, it should be discontinued. This generally denotes that the pigment is within the dermal layers of the skin.
Treatment of dermal pigmentation is quite challenging especially for people of color. There has been appreciable improvement with advanced exogenous ochronosis with the use of lasers. Unfortunately, more clinical, and long-term studies are needed to assess the safety and long-term results.
If brightening your skin is your goal, choose a fading product that is hydroquinone-free. Look for ingredients that are tyrosinase inhibitors. Such as:
- Vitamin A
- Kojic Acid
- Azelaic acid
- L-ascorbic acid – Vitamin C.
- Tranexamic acid.