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

Date of Report (Date of earliest event reported) April 25, 2012

WATSON PHARMACEUTICALS, INC.

(Exact Name of Registrant as Specified in Its Charter)

(862) 261-7000

(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 7.01. Regulation FD Disclosure.

On April 25, 2012, Watson Pharmaceuticals, Inc., a Nevada corporation (“Watson”) issued a press release announcing that Watson and Watson Pharma S.à r.l., a company incorporated in Luxembourg and wholly-owned subsidiary of Watson (“Purchaser”), entered into a Sale and Purchase Agreement (the “Purchase Agreement”), with Actavis Acquisition Debt S.à r.l., a company incorporated in Luxembourg (the “Vendor”), Nitrogen DS Limited, a company incorporated in the British Virgin Islands (“Nitrogen”), Landsbanki Islands hf., a company incorporated in Iceland (“Landsbanki”), ALMC Eignarhaldsfélag ehf., a company incorporated in Iceland (“ALMC”, together with Nitrogen and Landsbanki, the “Indirect Equity Holders”), ALMC hf., a company incorporated in Iceland, Argon Management S.à r.l., a company incorporated in the Grand Duchy of Luxembourg, the Managers party thereto, Deutsche Bank AG, London Branch, a branch of a company incorporated under the laws of the Federal Republic of Germany (“DB”, together with Landsbanki, the “Debt Holders” and the Debt Holders together with the Indirect Equity Holders and the Managers, the “Indirect Interest Holders”), pursuant to which Watson will acquire (i) the entire issued share capital of Actavis, Inc., a Delaware corporation, Actavis Pharma Holding 4 ehf., a company incorporated in Iceland, and Actavis S.à r.l., a company incorporated in Luxembourg (collectively, the “Companies”) and (ii) all the rights of the Vendor in certain indebtedness of the Companies.

On April 25, 2012, Watson also posted an investor presentation on its website regarding the transaction contemplated by the Purchase Agreement.

The press release and investor presentation are attached as Exhibits 99.1 and 99.2, respectively, hereto and incorporated herein by reference. The information in Item 7.01 of this report (including Exhibits 99.1 and 99.2) is being furnished and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”), nor shall it be deemed incorporated by reference in any filing under the Securities Act or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

In its press release and investor presentation, the Company discloses non-GAAP financial measures (as defined in Regulation G promulgated by the U. S. Securities and Exchange Commission) that exclude certain significant charges or credits that are important to an understanding of the Company’s ongoing operations. The Company believes that its inclusion of non-GAAP financial measures provides useful supplementary information to and facilitates analysis by investors in evaluating the Company’s performance and trends, and may be useful in assisting investors in evaluating the transaction contemplated by the Purchase Agreement. The determination of significant charges or credits may not be comparable to similar measures used by other companies and may vary from period to period. The Company uses both GAAP financial measures and the disclosed non-GAAP financial measures internally to evaluate and manage the Company’s operations and to better understand its business. These non-GAAP financial measures are in addition to, not a substitute for, or superior to, measures of financial performance prepared in accordance with GAAP.

Item 9.01. Financial Statements and Exhibits.

SIGNATURE

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

EXHIBIT INDEX