Obagi Medical Products Presents In Vitro Data Showing Its Topical Vitamin C Serums Provide Greater Absorption and Stability Than a Leading Competitor

Obagi Medical Products, Inc. (Nasdaq:OMPI), a leader in topical aesthetic and therapeutic skin health systems, announced the results of an in vitro study of their Obagi Professional-C and Obagi-C Rx Serums today at the American Academy of Dermatology’s Summer Academy Meeting in Chicago. The data show that Obagi-C Rx Serum (4% hydroquinone, 10% L-ascorbic acid) provided a more than 10-fold greater absorption of vitamin C than the leading competitive product, Skinceuticals(R) 20%. The Obagi Professional-C Serum (20%) resulted in a more than 5-fold greater absorption of vitamin C than the leading competitive product.

In addition, both Obagi Medical Vitamin C Serums were proven to have greater stability than the leading competitor, which is important given that topical vitamin C products can be unstable thus potentially making them less efficacious.

“Vitamin C is an important antioxidant and is essential for collagen production, which keeps skin looking young and healthy. It’s also very sensitive to numerous external conditions, so it is important to use a formulation that has a high level of penetration and is stable,” said Harry Agahigian, lead investigator of the study. “The studies showed that the Obagi Medical vitamin C formulations provide much better absorption and greater stability versus the competitive product.”

Key Findings:

Investigators sought to evaluate the absorption and stability of the three serums and the Obagi serums performed better in each objective of the study.

In an in vitro test evaluating absorption of vitamin C, each of the three serums (Obagi-C Rx Serum, Obagi Professional-C 20% Serum and the 20% L-ascorbic acid-based leading competitor product) was tested by being applied to cadaver skin for a period of 19 hours at 37 degrees C. The total absorption of vitamin C in each product was:

— 148 micro-g with Obagi-C Rx Serum (31% of baseline amount)

— 66 micro-g with Obagi Professional-C Serum (11% of baseline amount)

— 12 micro-g with the competitor product (2% of baseline amount).

In a stability test, the serums, Obagi-C Rx Serum (4% hydroquinone, 10% L-ascorbic acid), Obagi Professional-C Serum (20% L-ascorbic acid), and leading competitor 20% L-ascorbic acid, were stored at 40 degrees C and the vitamin C content was measured at 1 and 3 months. An additional stability test was performed by storing the products at 45 degrees C for 1 month. Here, vitamin C content was also measured.

 Stability Test 1        Stability Test 2 ---------------------------------------------------------------------- Product                One Month          One Month      Three Months Reduction (45      Reduction (40  Reduction degrees C)         degrees C)     (40 degrees C) ---------------------------------------------------------------------- Obagi-C Rx Serum       2%                 None           2% ---------------------------------------------------------------------- Obagi Professional-C Serum                 14%                8%             17% ---------------------------------------------------------------------- Leading Competitive Product               29%                11%            41% ---------------------------------------------------------------------- 

“We are proud that our vitamin C products provide such clinically significant advantages over the competitive product,” said Steven Carlson, Chief Executive Officer of Obagi Medical Products. “Obagi Medical’s top priority is to provide highly effective differentiated skin care products that are based in real science. We do that by working closely with the top experts in the skin care field.”

About The Obagi-C Rx System

The patented Obagi-C Rx Early Intervention System is a complete skincare program that proactively corrects the early signs of damage to help restore and maintain healthy, youthful-looking skin. It is the first and only regimen offering the benefits of both prescription strength hydroquinone and stable vitamin C in one comprehensive system. It is available through physicians, including dermatologists and plastic surgeons.

About Obagi Professional-C Serums

Obagi Medical Products Vitamin C Serums deliver greater penetration to the skin thus delivering more antioxidant benefits. Obagi Professional-C Serums use stabilized ascorbic acid – the only form of vitamin C that can be readily absorbed by the skin. Patients may choose from 4 different concentrations: 20%, 15% or 10% concentrations for the skin and a 5% concentration for around the eyes.

About Obagi Medical Products, Inc. (www.obagi.com)

Obagi Medical Products develops and commercializes skin health products for the dermatology, plastic surgery, and related aesthetic markets. Using its Penetrating Therapeutics(TM) technologies, Obagi Medical’s products are designed to improve penetration of agents across the skin barrier for common and visible skin conditions in adult skin including chloasma, melasma, senile lentigines, acne vulgaris and sun damage. The history of Obagi’s skin care product introductions is as follows: Obagi Nu-Derm(R), 1988; Obagi-C(R) Rx (the first and only prescription-strength vitamin C and hydroquinone system), 2004; Obagi(R) Professional-C (a line of highly stable vitamin C serums), 2005; Obagi(R) Condition and Enhance for use with cosmetic procedures to enhance patient outcomes and satisfaction, 2006; Obagi ELASTIderm(TM) eye treatment and Obagi CLENZIderm(R) M.D. acne therapeutic systems, 2007; a formulation of Obagi CLENZIderm(R) M.D. Systems for normal to dry skin, June 2007; and Obagi ELASTIderm(TM) Decolletage System, January 2008. Obagi’s products are only available through physicians.

Forward Looking Statements

There are forward-looking statements contained herein, which can be identified by the use of forward-looking terminology such as the words “believes,””expects,””may,””will,””should,””potential,””anticipates,””plans,” or “intends” and similar expressions. Such forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause actual results, events or developments to be materially different from the future results, events or developments indicated in such forward-looking statements. Such factors include, but are not limited to the intense competition our products face and will face in the future, the level of market acceptance of our products, the possibility that our products could be rendered obsolete by technological or medical advances, the possibility that we may become involved in intellectual property claims and litigation that could adversely affect the profitability of or our ability to sell our products, the possibility that our products may cause undesirable side effects and the fact that our ability to commercially distribute our products may be significantly harmed if the regulatory environment governing our products changes. A more detailed discussion of these and other factors that could affect results is contained in our filings with the U.S. Securities and Exchange Commission, including our Form 10-K for the year ended December 31, 2007. These factors should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements. No assurance can be given that the future results covered by the forward-looking statements will be achieved. All information in this press release is as of the date of this press release and Obagi Medical Products does not intend to update this information.