Hydroquinone
Hydroquinone is the standard ingredients use in hyperpigmentation treatment creams. For the over-the-counter products, the hydroquinone concentration is no more than 2% while the prescription ones usually does not exceed more than 4%.
Some claim that hydroquinone is not safe to use. It may cause ochronosis, an untreatable skin discoloration when used in very high concentration or on long-term basis.
When you shop for hydroquinone creams, it is important to check the concentration. Don’t buy it if the label does not state the strength of hydroquinone because you don’t know if it is safe to use. Some imported skin brightening creams exceed the allowed hydroquinone concentration and even some of their labels may report the wrong concentration.