UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

December 5, 2012

Date of Report (Date of earliest event reported)

Medicis Pharmaceutical Corporation

(Exact name of registrant as specified in its charter)

7720 North Dobson Road

Scottsdale, Arizona 85256

(Address of principal executive offices) (Zip Code)

(602) 808-8800

(Registrant’s telephone number, including area code)

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Item 8.01 Other Events.

As previously reported, on November 7, 2012, Q-Med AB (“Q-Med”) filed a complaint (the “Complaint”) against Medicis Pharmaceutical Corporation (the “Company”), HA North American Sales AB, a wholly-owned subsidiary of the Company (“HANA”) and Medicis Aesthetics Holdings Inc., in the United States District Court for the Southern District of New York (the “Court”). The Complaint seeks, among other things, a preliminary injunction prohibiting the Company from transferring its rights under its agreements with Q-Med to Valeant Pharmaceuticals, Inc. (“Valeant”) as a result of the previously announced proposed merger between the Company and Valeant (the “Merger”).

On December 5, 2012, the Court entered an order dismissing the lawsuit with prejudice, subject to leave within 30 days to request that the action be restored. As previously disclosed, the parties intend to close the Merger on December 11, 2012, subject to satisfaction of remaining customary closing conditions, including the approval of the Company’s stockholders at the Company’s special meeting of stockholders scheduled for December 7, 2012.

Forward-Looking Statements

Certain statements contained in this document contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of historical facts, including, among others, statements regarding the anticipated merger, are forward-looking statements. Those statements include statements regarding the intent, belief or current expectations of the Company and members of its management team, as well as the assumptions on which such statements are based, and generally are identified by the use of words such as “believes,” “expects,” “anticipates,” “intends,” “estimates,” “plan,” “will,” “may,” “intend,” “guidance” or similar expressions. Because these statements reflect the Company’s current views, expectations and beliefs concerning future events, these forward-looking statements involve risks and uncertainties. Many of these factors are beyond the Company’s ability to control or predict. Such factors include, but are not limited to, any conditions imposed in connection with the merger, approval of the merger agreement by the Company’s stockholders, the satisfaction of various other conditions to the closing of the merger, and other factors including those detailed from time to time in the Company’s periodic reports filed with the Securities and Exchange Commission (SEC), including current reports on Form 8-K, quarterly reports on Form 10-Q and annual reports on Form 10-K, particularly the discussion under the caption “RISK FACTORS” in its annual report on Form 10-K for the year ended Dec. 31, 2011, which has been filed with the SEC. The forward-looking statements in this press release are qualified by these risk factors. These are factors that, individually or in the aggregate, could cause the Company’s actual results to differ materially from expected and historical results. These risks and uncertainties should be considered in evaluating any forward-looking statements contained herein. The Company assumes no obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.