Hydroquinone is a skin-lightening agent used to treat pigmentation. It has been the gold standard for treating hyperpigmentation for more than 50 years. Clinically, it is used to treat areas of dyschromia such as in melasma, chloasma, solar lentigines, freckles and post-inflammatory hyperpigmentation. It can also help reduce the appearance of acne scars. Hydroquinone can be purchased over-the-counter in concentrations up to 2%. A prescription is required for concentrations higher than 2% and the highest dose available is 4%. Doses higher than 2% need to be administered carefully by a medical professional. Hydroquinone can be mixed into a cream or a serum and it is often best used as part of a combination with other medications such as retinoids and corticosteroids.
How does hydroquinone work?
Hydroquinone acts as a skin depigmentation agent by inhibiting the process of melanin synthesis. Hydroquinone stops the conversion of L-DOPA to melanin by inhibiting the enzyme tyrosinase. It also acts to increase the breakdown of melanosomes in melanocytes. Melanocytes are the melanin forming cells in the skin. Melanosomes are the structures within the melanocytes that are directly responsible for making melanin. Hydroquinone is thought to modify the formation of melanosomes and/or reduce their activity, thus reducing the amount of melanin produced.
Hydroquinone should always be used under the supervision of a doctor so as to prevent unwanted side effects. We generally recommend using a safe dose of hydroquinone once or twice per day for a period of 3 to 6 months. We will check in with you after 3 months to see if you have noticed any improvement with the hydroquinone. If you have not seen any results after 3months we will discontinue this medication. After 6 months of use, we will generally stop the medication for a period to decrease the risk of side effects. Following this, we may recommend a safe maintenance dose. We recommend applying hydroquinone only to the hyperpigmented areas of your skin as it will lighten normal skin as well. Avoid applying near the eyes and mouth. Apply hydroquinone to your skin first then wait a few minutes before applying sunscreen, moisturiser and/or makeup.