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): December 1, 2010 (December 1, 2010)

Endo Pharmaceuticals Holdings Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (610) 558-9800

Not Applicable

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:

On December 1, 2010, Endo issued a press release announcing that it had completed its acquisition of all of the issued and outstanding capital stock of Generics International (US Parent), Inc (d/b/a Qualitest Pharmaceuticals) from an affiliate of Apax Partners, L.P.

A copy of the press release is furnished as Exhibit 99.1.

The press release includes financial measures that are not in conformity with accounting principles generally accepted in the United States. We refer to these as non-GAAP financial measures. Specifically, the release refers to adjusted diluted earnings per share. Endo refers to these non-GAAP financial measures in making operating decisions because it believes they provide meaningful supplemental information regarding the company’s operational performance. The company included these non-GAAP financial measures in the release because it believes they are useful to investors in allowing for greater transparency related to supplemental information used by Endo in its financial and operational decision-making. In addition, Endo has historically reported similar non-GAAP financial measures to its investors. Further, Endo believes that these non-GAAP financial measures may be useful to investors as it is aware that certain of its significant stockholders utilize these measures to evaluate its financial performance. Finally, these measures are considered by the Compensation Committee of Endo’s Board of Directors in assessing the performance and compensation of substantially all of its employees, including its executive officers. Investors are encouraged to review the reconciliation of the non-GAAP financial measures used in the release to their most directly comparable GAAP financial measures.

The information in this Item 7.01 and in Exhibit 99.1 shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section. The information contained in this Item 7.01 and in Exhibit 99.1 shall not be incorporated into any registration statement or other document filed with the Securities and Exchange Commission by the company, whether made before or after the date hereof, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Not applicable.

Not applicable.

Not applicable.

SIGNATURES

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.

Dated: December 1, 2010

INDEX TO EXHIBITS