Hydroquinone
As per most medical journals, hydroquinone is considered as the foremost topical ingredient used for inhibiting melanin production. Its components consist of very powerful antioxidant abilities.
Hyper Pigmentation
Hydroquinone is thus viewed as the most effective topical treatment used for skin lightening. Numerous clinical studies as well as research have been done on its effectiveness as well as its possible side-effects. Hydroquinone does not bleach the skin, but works by attacking a certain enzyme, tyrosinase, crucial to the production of melanin. It takes a few weeks in order to see a significant change in the skin pigmentation, as the existing melanin needs to be removed by natural exfoliation. Thus, hydroquinone as well as other melanin inhibiting agents are, at times, combined with powerful alpha hydroxyl acids to aid in exfoliation. But this increases the risk of skin irritation as each of these, in itself, is a potential skin irritant. This is especially true when the concentration gets higher than 4%. At times, in case this percentage is used, cortisone will be added as an anti-inflammatory ingredient. Hydroquinone can get unstable in cosmetic formulas, as when it is exposed to air or light, it may turn a strange shade of brown. In case you are considering purchasing a hydroquinone product, buy one that is packaged in a non-transparent container to ensure that its exposure to air as well as light is minimal. Hence, a product that is packaged in a jar is not recommended. Hydroquinone can even be purchased over-the-counter in concentrations of 0.5-2%, as anything higher than this requires a prescription. With short term use, the side effects tend to be mild, especially in case a lower concentration is used. Animal studies have shown that high dosages have the potential to even cause cancer. Thus its use is banned in many countries, including France. It can even cause a condition known as ochronosis, which is a bluish-black colouring of the tissue.
Continuing research is required in order to evaluate the risks associated with hydroquinone use as well as to determine the appropriate and safe doses. The fact is that that high-dosage, long term use may even cause cancer in laboratory mice but that does not necessarily correlate to the same outcome in humans. Hydroquinone treatment has already been used successfully by millions of people over many decades. Until further study has been conducted, it may be prudent to use the lower percentage concentrations of hydroquinone unless there is some compelling requirement for higher dosage. In that case, it should only be administered under close medical supervision. At this time, there is no substantial evidence of serious risks while using the lower concentrations of hydroquinone as well as using it for a short duration. However, it is important to keep up with the clinical studies as well as to follow the developments concerning hydroquinone.
Arbutin
It is derived from the leaves of bearberry, cranberry, mulberry or the blueberry shrubs. It is also found in most types of pears. Though some consider it as a unique skin-lightening product, it is actually quite similar to hydroquinone. It, too, attacks the enzyme tyrosinase which is required to suppress the body’s production of melanin. Arbutin seems to have lesser side effects than hydroquinone at the same concentrations. This may be due to its more gradual release into the system. It is generally available in concentrations that range from 3-7%.
Arbutin is considered gentler to the skin as compared to hydroquinone and hence causes less skin irritations. The concentration protocols are yet to be established for arbutin, as it is not known how much of it is needed in order to lighten skin when it is added to a cosmetic formulation. Many of the cosmetic companies use plant extracts containing arbutin but there is little clinical evidence showing that the plant extract source of arbutin has any impact on the skin, especially in the tiny amounts that is used in cosmetics.
Kojic acid
This is a naturally occurring substance produced as well as found in many species of fungi, especially Asperigillis oryzae, having the Japanese name koji. It is a by-product in the fermentation process of malting rice, used in the manufacturing of sake, which is the Japanese rice wine. Some research indicates that kojic acid is quite effective in inhibiting the production of melanin; it can also be unstable when it is used in cosmetic formulations. Besides, exposure to air or sunlight can make it turn brown and lose its efficacy. In order to help alleviate this product, many cosmetic companies tend to use kojic dipalmitate as an alternative as it is more stable. There is an ongoing debate as to whether this formulation is as effective as kojic acid itself in skin lightening. Furthermore, there is controversial research which suggests that kojic acid in large doses may have carcinogenic properties.
Azelaic acid
This is a component of grains, such as wheat, barley, as well as rye. It is a natural substance that is derived from a common yeast that lives on normal skin. It is applied topically as a cream formulation at a 20% concentration. It is used to treat acne, but research has shown it to be very effective for skin discolorations, as it may be an inhibitor of melanin production. With the safety concerns expressed about the use of hydroquinone, azelaic acid does make a more attractive alternative treatment for melasma as well as other hyper pigmentation disorders. However, topical azelaic acid has hardly any effect on age spots or freckles.
Glabridin
It is the main compound that is found in licorice extract. It is thought to work on the enzyme tyrosinase which, helps to inhibit the production of melanin. It has been used all over the world as an effective skin lightening agent since a long time as there seem to be little or no side effects associated with its use. However, no clinical studies have been performed on glabridin in order to successfully establish its effectiveness or what its optimum concentration should be.
Topical retinoids
These have been successfully used in the treatment of melasma as well as other skin pigmentation disorders for many years. In case they are used alone, they are not as effective as hydroquinone and it may take six months or more before any noticeable results are realized. These are believed to work by accelerating the natural exfoliation process, which is, the sloughing off of external skin cells. Some believe that they also inhibit the production of melanin but that is not a well documented claim.
People with hyper pigmentation disorders, who do not respond to treatment with hydroquinone only may have more positive results when tretinoin, a common topical retinoid, is added to their treatment regimen. But as both these compounds are potential skin irritants, you need to use them in combination with extreme caution. The addition of cortisone to the combination of hydroquinone and tretinoin can drastically reduce the amount of skin irritation that is sometimes associated with their use.
Alpha hydroxy acids
These are also known as AHAs, which are primarily in the form of lactic acid as well as glycolic acid, as these are the most researched forms of AHAs since they have a molecular size which allows effective penetration into the top layers of the skin. It is generally thought that AHAs in concentrations of 4% to 15% are not effective in inhibiting the production of melanin and will not actually lighten skin discolorations. Their true benefit lies in their ability to aid in accelerating cell turnover rates as well as removing unhealthy or abnormal layers of superficial skin cells, also known as exfoliation. This is where hyperpigmented cells tend to accumulate. Hence, when the exfoliation process occurs, these hyperpigmented cells too are taken away. However, other research shows that lactic and glycolic acids can definitely inhibit melanin production besides their successful use as exfoliants.
Just like laser treatments, alpha hydroxy acid peels, when used in 50% concentrations or more, may remove skin discolorations. Ensure that only a qualified physician performs these types of facial peels.
Laser resurfacing as well as chemical peels
Whether it is performed with a laser or a chemical agent, skin resurfacing significantly reduces hyperpigmented skin. A chemical peel uses a chemical solution in order to improve as well as smooth the texture of the facial skin by removing the damaged outer layers. Alpha hydroxy acids are the mildest of the peel formulas and hence, they produce light peels. Trichloroacetic acid (TCA) can be used in various concentrations but it is most commonly used for the medium-depth peeling. Hyper pigmentation problems are usually treated with TCA, whose results are usually less dramatic than and not as long lasting as those of a phenol peel. In fact, more than one TCA peel may be required in order to achieve the desired results. Phenol is the strongest of the chemical solutions as it produces a very deep peel, and is mainly used to treat people with very coarse facial wrinkles, areas of blotchy as well as sun-damaged skin, besides pre-cancerous growths. Phenol can also lighten the treated areas. It is a very powerful chemical and should be used with caution. It is primarily used on the face; and scarring may result in case it’s applied to the neck or to the other areas of the body. Because of the high cost, side effects, as well as inconvenience of chemical peels, these procedures are rarely used in order to treat hyper pigmentation or hypopigmentation.
Intense pulsed light and nonablative laser
Nonablative laser as well as light therapy is a relatively novel approach used for the treatment of sun-damaged, scarred or injured skin. This includes hyper pigmentation. High intensity heat is directed towards the affected areas, which eliminates the pigmented lesions without causing much damage to the surrounding skin. Intense Pulsed Light (IPL) as well as pulsed dye lasers can both be used in order to treat hyperpigmentation. On the one hand, very little recovery time is there after undergoing this type of therapy. Thus, people can usually continue with their normal routines. However, these treatments are expensive and though the effects can be immediate as well as dramatic, a successful outcome cannot always be guaranteed.
Cryotherapy
This is an alternative to laser treatment, which uses liquid nitrogen for controlled destruction of the skin cells causing the skin to naturally regenerate itself. Excess melanin tends to come to the surface and peels off in a few days. However, this kind of a treatment is generally used for small, localized areas of hyperpigmentation, like age spots. Cryotherapy is as effective as laser treatments, but without the high cost. Beside, it is less likely to cause side effects and is regarded as being more reliable.