Exhibit 99.4

Announcement to DSCM customers

March 24, 2011

Dear Valued Customer,

Today, we are excited to inform you that drugstore.com has entered into a formal agreement to be acquired by Walgreens. This combination will create the most convenient multi-channel retailer of health, beauty, wellness and pharmacy products and services. As a result, you will ultimately have even greater access to the products you want, where and when you want them.

Please be assured, we intend to maintain separate branding of our websites, so you will continue to be able to shop on drugstore.com, Beauty.com and our family of sites.

We remain committed to providing the wide selection of products you love today and look forward to building on the value, convenience and service you’ve come to expect.

The full text press release is available at: investor.drugstore.com

Further information regarding Walgreens products and service offerings is available at www.walgreens.com

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Additional Information about the Transaction

The information in this communication is not, and is not intended to be, a solicitation of proxies or an offer of securities. drugstore plans to file with the SEC and mail to its stockholders a Proxy Statement in connection with the transaction. The Proxy Statement will contain important information about Walgreens, drugstore, the transaction and related matters. Investors and security holders are urged to read the Proxy Statement carefully when it is available. Investors and security holders will be able to obtain free copies of the Proxy Statement and other documents filed with the SEC by drugstore through the web site maintained by the SEC at www.sec.gov and by contacting drugstore Investor Relations at (212) 331-8424. In addition, investors and security holders will be able to obtain free copies of the documents filed with the SEC on drugstore’s website at www.drugstore.com.

Participants in the Acquisition of drugstore

drugstore.com and its directors and officers and certain other members of management and employees may be deemed to be participants in the solicitation of proxies from its stockholders in connection with the Transaction. Information regarding these persons who may, under the rules of the SEC, be considered participants in the solicitation of drugstore’s stockholders in connection with the proposed transaction will be set forth in the Proxy Statement described above when it is filed with the SEC. Additional information regarding drugstore’s executive officers and directors is included in drugstore’s definitive proxy statement, which was filed with the SEC on April 30, 2010. You can obtain free copies of this document from drugstore using the contact information above.

Forward-Looking Statements

Information set forth in this announcement contains forward-looking statements, which involve a number of risks and uncertainties. These statements include those regarding the transaction, the integration process, and our expectations for our operations. These statements are not guarantees of future performance and are subject to risks, uncertainties and assumptions that could cause actual results to vary materially from those indicated, including: the ability to obtain regulatory approvals of the transaction on the proposed terms and schedule; the failure of drugstore’s stockholders to approve the transaction; the risk that the businesses will not be integrated successfully; the risk that the cost savings and any other synergies from the transaction may not be fully realized or may take longer to realize than expected; disruption from the transaction making it more difficult to maintain relationships with customers, employees or suppliers; competition and its effect on pricing, spending, third-party relationships and revenues; and other factors described in Walgreens Annual Report on Form 10-K for the year ended August 31, 2010, drugstore.com’s Annual Report on Form 10-K for the year ended January 2, 2011 and their respective subsequent SEC filings, which risks and uncertainties are incorporated herein by reference. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. Except to the extent required by law, Walgreens and drugstore.com disclaim any obligation to update any forward-looking statements after the distribution of this announcement, whether as a result of new information, future events, changes in assumptions, or otherwise.

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