- If in doubt, throw it out! Discard any hydroquinone-containing cream that turns color (usually dark yellow or brown from white) since this means the hydroquinone has become oxidized and is no longer active. In fact, oxidized hydroquinone produces by-products that may be more irritating and toxic than full-strength hydroquinone itself.2
- Always use sunscreen! If you need another incentive to use sunscreen (or better yet, sun-block) consider this: reducing direct sun exposure increases your chances of preventing melasma (one of the most difficult hyperpigmentation conditions to treat) as well as decreasing your risk of melanoma (a potentially deadly, and discoloring, form of skin cancer).1
- Test a small area first. Typical side effects include skin irritation, and it is recommended that you test a small, inconspicuous area first before continued use. Although rare, some patients with darker skin tones have experienced a serious hyperpigmentation condition called exogenous ochronosis, which is a blue-black pigmentation that may be related to long-term usage of hydroquinone at high concentrations.3
- Plensdorf, Scott and Martinez, Joy. American Family Physician Volume 79, Issue 2: Common Pigmentation Disorders. MD Consult: American Academy of Family Physicians. [Online] January 2009. http://www.mdconsult.com/das/article/body/178618016-2/jorg=journal&source=MI&sp=21650863&sid=0/N/680808/1.html?issn=0002-838X.
- Alam, Murad, et al. Cosmetic Dermatology for Skin of Color. s.l. : McGraw Hill Professional, 2008. ISBN 007148776X, 9780071487764.
- Bandyopadhyay, D. Topical treatment of melasma. Indian Journal of Dermatology. [Online] November 5, 2009. http://www.e-ijd.org/article.asp?issn=0019-5154;year=2009;volume=54;issue=4;spage=303;epage=309;aulast=Bandyopadhyay. DOI 10.4103/0019-5154.57602.