Organization and Basis of Presentation	12 Months Ended
Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation Opiant Pharmaceuticals, Inc. (the “Company”), a Nevada corporation, is a specialty pharmaceutical company developing medicines for addictions and drug overdose. The Company was incorporated in the State of Nevada on June 21, 2005 as Madrona Ventures, Inc. and, on September 16, 2009, the Company changed its name to Lightlake Therapeutics Inc. On January 28, 2016, the Company again changed its name to Opiant Pharmaceuticals, Inc. The Company also has developed a treatment to reverse opioid overdoses, which is now known as NARCAN®. On October 2, 2017, the Company changed its state of incorporation from the State of Nevada to the State of Delaware pursuant to an Agreement and Plan of Merger, dated October 2, 2017, whereby the Company merged with and into its recently formed, wholly-owned Delaware subsidiary, Opiant Pharmaceuticals, Inc. Pursuant to the Agreement and Plan of Merger, (i) the Company merged with and into its Delaware subsidiary, (ii) the Company's separate corporate existence in Nevada ceased to exist,(iii) the Company's Delaware subsidiary became the surviving corporation, (iv) each share of the Company's common stock, $0.001 par value per share ("Common Stock"), outstanding immediately prior to the effective time was converted into one fully-paid and non-assessable share of Common Stock of Opiant Pharmaceuticals, Inc., a Delaware corporation, and (v) the certificate of incorporation and bylaws of the Company's Delaware subsidiary were adopted as the Company's certificate of incorporation and bylaws at the effective time of the merger. The merger and the Agreement and Plan of Merger were approved by the Company's Board of Directors (the "Board") and stockholders representing a majority of the Company's outstanding Common Stock. On December 8, 2017, the Board of Directors, acting pursuant to Section 5.1 of the Company’s Bylaws, approved a resolution changing the Company’s fiscal year-end from July 31 to December 31. The Company made this change to align its fiscal year end with other companies within its industry.

Organization and Basis of Presentation

Opiant Pharmaceuticals, Inc. (the “Company”), a Nevada corporation, is a specialty pharmaceutical company developing medicines for addictions and drug overdose. The Company was incorporated in the State of Nevada on June 21, 2005 as Madrona Ventures, Inc. and, on September 16, 2009, the Company changed its name to Lightlake Therapeutics Inc. On January 28, 2016, the Company again changed its name to Opiant Pharmaceuticals, Inc. The Company also has developed a treatment to reverse opioid overdoses, which is now known as NARCAN®.

On October 2, 2017, the Company changed its state of incorporation from the State of Nevada to the State of Delaware pursuant to an Agreement and Plan of Merger, dated October 2, 2017, whereby the Company merged with and into its recently formed, wholly-owned Delaware subsidiary, Opiant Pharmaceuticals, Inc. Pursuant to the Agreement and Plan of Merger, (i) the Company merged with and into its Delaware subsidiary, (ii) the Company's separate corporate existence in Nevada ceased to exist,(iii) the Company's Delaware subsidiary became the surviving corporation, (iv) each share of the Company's common stock, $0.001 par value per share ("Common Stock"), outstanding immediately prior to the effective time was converted into one fully-paid and non-assessable share of Common Stock of Opiant Pharmaceuticals, Inc., a Delaware corporation, and (v) the certificate of incorporation and bylaws of the Company's Delaware subsidiary were adopted as the Company's certificate of incorporation and bylaws at the effective time of the merger. The merger and the Agreement and Plan of Merger were approved by the Company's Board of Directors (the "Board") and stockholders representing a majority of the Company's outstanding Common Stock.

On December 8, 2017, the Board of Directors, acting pursuant to Section 5.1 of the Company’s Bylaws, approved a resolution changing the Company’s fiscal year-end from July 31 to December 31. The Company made this change to align its fiscal year end with other companies within its industry.