An antioxidant system, most commonly the combination of sodium sulfite and
Hydroquinone is applied topically just to the hyperpigmented skin only, twice daily for 3 months, after which time many patients maintain their improvement by using it twice each week. If there has been no benefit after 3 months of treatment, then the hydroquinone should be stopped.
Apply a broad-spectrum sunscreen with a high SPF (SPF 50) daily, especially in the morning as UV exposure can worsen hyperpigmentation and counteract the effects of hydroquinone.
Store in the refrigerator. Do not freeze.
In all formulations, hydroquinone is unstable turning brown upon contact with air. Once the hydroquinone has oxidized, it is no longer active and should be discarded.
Solutions of hydroquinone are stabilized against deterioration in color and odor with age by the addition to the solution of small amounts of citric acid. Up to about 1 percent citric acid by weight of the solution may be used, although it is preferred that this amount be between 0.005 percent and 0.05 percent.
Hydroquinone has a pretty short shelf life. After a couple of months, it can start to break down and lose its potency, meaning it becomes less effective.
Avoid irritants: Be mindful of other skincare products or ingredients that may potentially irritate your skin. Avoid using harsh cleansers, exfoliants, or other products that can cause irritation or sensitivity while using hydroquinone.
Do not apply to sunburned areas or if you have a skin wound in the area of application. Most cosmetics, sunscreens, and moisturizing lotions may be worn over this medicine.
No, the hydroquinone won't hurt you if it turns brown but it won't be effective either because it has oxidized or degraded. I would recommend throwing it out after a year or sooner, if it turns brown throughout the tube.
Hydroquinone can be applied morning and night. excess pigmentation such as the neck and back of hands. Allow product to fully absorb into skin before applying moisturizer or any other skin care products.
The lesions may develop gradually over 6 months to 3 years or longer. [8] Two recent case reports from India mention the occurrence of EO with use of 2% hydroquinone preparations for 7–8 years.
A major key to hydroquinone is short-term use. You can slather it on twice daily for at least six weeks (and no more than six months). After one to three months, you should start to see your hyperpigmentation fade away.
Hydroquinone is a white, odorless, crystalline solid with an extremely low vapor pressure. It is moderately soluble in water and highly soluble in alcohol.
Adverse Effects
Rarely ochronosis - ochronosis is a blue-black or gray-blue discoloration; it is rare and more commonly seen in patients that use a high concentration of hydroquinone for a long period on large areas of the body.
Combination Tip: Combining hydroquinone with Vitamin C may improve overall efficacy, but due to potential sensitivities, this combination should only be used under the supervision of a dermatologist. Sunscreen: How It Works: Sunscreen is essential for preventing further hyperpigmentation caused by UV exposure.
Hydroquinone and retinols work well together because retinols help hydroquinone penetrate deeper into the skin to work more effectively. Retinols can also protect hydroquinone from oxidation, which can cause it to degrade.
Tretinoin is an anti-aging powerhouse, meaning it should have no problem dispatching fine lines and wrinkles. It does not work for deeper wrinkles. Hydroquinone doesn't work at all against fine lines and wrinkles, so stick to the collagen-boosting power of tretinoin.
FDA has received reports of serious side effects including skin rashes, facial swelling, and ochronosis (discoloration of skin) from the use of skin lightening products containing hydroquinone.
Hydroquinone and Retin-A (Tretinoin)
When used with Hydroquinone, it can speed up the process of fading hyperpigmentation.
Apply hydroquinone in a thin layer to affected areas of the face. Do not apply it to other areas of the face; otherwise, it will bleach that skin.
Storage: Store hydroquinone at room temperature (between 15-30° C or 59-86° F) away from moisture, heat, and direct light in its original container. You can refrigerate this medicine (between 36-46° F) but you should not freeze it.
INGREDIENTS CAN OXIDIZE:
Generally, you can tell that something has oxidized because it will turn a yellow-ish or brown-ish color. Sometimes this color shift doesn't greatly impact the efficacy of the product. But sometimes, this oxidation can be a sign that the ingredients inside the product are no longer potent.
Deoxyarbutin. Deoxyarbutin (Chemical structure 22, Figure 4) was shown to be an effective inhibitor of mushroom TYR in vitro more potent than hydroquinone and arbutin [100,101].