Overview	3 Months Ended
Mar. 31, 2019
Accounting Policies [Abstract]
Overview	Note 1. Overview Soleno Therapeutics, Inc. (the “Company” or “Soleno”) was incorporated in the State of Delaware on August 25, 1999, and is located in Redwood City, California. On May 8, 2017, Soleno received stockholder approval to amend its Amended and Restated Certificate of Incorporation to change its name from “Capnia, Inc.” to “Soleno Therapeutics, Inc.” The Company was initially established as a diversified healthcare company that developed and commercialized innovative diagnostics, devices and therapeutics addressing unmet medical needs, which consisted of: precision metering of gas flow technology marketed as Serenz ^® Allergy Relief, or Serenz; CoSense ^® End-Tidal Carbon Monoxide (ETCO) Monitor, or CoSense, which measures ETCO and aids in the detection of excessive hemolysis, a condition in which red blood cells degrade rapidly and which can lead to adverse neurological outcomes; and, products that included temperature probes, scales, surgical tables, and patient surfaces. The Company’s previously wholly-owned subsidiary, NeoForce, Inc., or NFI, through which the Company acquired substantially all of the assets of an unrelated privately-held company, NeoForce Group, Inc., or NeoForce, also marketed innovative pulmonary resuscitation solutions for the inpatient and ambulatory neonatal markets. The Company acquired Essentialis, Inc., or Essentialis, through a merger, or the Merger, on March 7, 2017, pursuant to Agreement and Plan of Merger dated December 22, 2016. Essentialis’s efforts prior to the Merger were focused primarily on developing and testing product candidates that target the ATP-sensitive potassium channel, a metabolically regulated membrane protein whose modulation has the potential to impact a wide range of rare metabolic, cardiovascular, and CNS diseases. Essentialis has tested Diazoxide Choline Controlled Release Tablet, or DCCR, as a treatment for Prader-Willi Syndrome, or PWS, a complex metabolic/neurobehavioral disorder. DCCR has orphan designation for the treatment of PWS in the United States, or U.S., as well as in the European Union, or E.U. Consummation of the Merger was subject to various closing conditions, including the Company’s consummation of a financing of at least $8.0 million at, or substantially contemporaneous with, the closing of the Merger, which occurred on March 7, 2017 and the receipt of stockholder approval of the Merger at a special meeting of its stockholders, which was held on March 6, 2017. Subsequent to the acquisition of Essentialis, the Company determined to divest, sell or otherwise dispose of the CoSense, NFI and Serenz businesses. Accordingly, and pursuant to ASC 205-20-45-10, any assets and liabilities related to the discontinued activities of CoSense, NFI and Serenz have been presented separately in the balance sheet as held for sale items, and the related operations reported herein for the CoSense, NFI and Serenz activities are reported as discontinued operations in the statements of operations. The Company determined to divest, sell or otherwise dispose of the CoSense, NFI and Serenz businesses in order to focus on the development and commercialization of novel therapeutics for the treatment of rare diseases. The Company’s current research and development efforts are primarily focused on advancing its lead candidate, DCCR tablets for the treatment of PWS, into late-stage clinical development. The Company sold its entire interest in NFI in a stock transaction that was completed on July 18, 2017, pursuant to a Stock Purchase Agreement dated July 18, 2017, or the NFI Purchase Agreement, entered into with Neoforce Holdings, Inc., a wholly-owned subsidiary of Flexicare Medical Limited, a privately-held United Kingdom company, for $720,000 and adjustments for inventory and the current cash balances held at NFI. On December 4, 2017, Soleno, and Capnia, Inc., a Delaware corporation, or Capnia, entered into a joint venture with OptAsia Healthcare Limited, or OAHL. The purpose of the joint venture is to develop and commercialize medical monitors, including CoSense, that measure end-tidal carbon monoxide in breath to assist in the detection of excessive hemolysis in neonates, a condition in which red blood cells degrade rapidly and which can lead to adverse neurological outcomes. The Company has previously charged to expense all previously-held assets related to its Serenz operations, and there are no remaining Serenz assets, liabilities or operations related to the Company’s previous Serenz-related business.

Overview

3 Months Ended

Mar. 31, 2019

Note 1. Overview

Soleno Therapeutics, Inc. (the “Company” or “Soleno”) was incorporated in the State of Delaware on August 25, 1999, and is located in Redwood City, California. On May 8, 2017, Soleno received stockholder approval to amend its Amended and Restated Certificate of Incorporation to change its name from “Capnia, Inc.” to “Soleno Therapeutics, Inc.” The Company was initially established as a diversified healthcare company that developed and commercialized innovative diagnostics, devices and therapeutics addressing unmet medical needs, which consisted of: precision metering of gas flow technology marketed as Serenz ^® Allergy Relief, or Serenz; CoSense ^® End-Tidal Carbon Monoxide (ETCO) Monitor, or CoSense, which measures ETCO and aids in the detection of excessive hemolysis, a condition in which red blood cells degrade rapidly and which can lead to adverse neurological outcomes; and, products that included temperature probes, scales, surgical tables, and patient surfaces.

The Company’s previously wholly-owned subsidiary, NeoForce, Inc., or NFI, through which the Company acquired substantially all of the assets of an unrelated privately-held company, NeoForce Group, Inc., or NeoForce, also marketed innovative pulmonary resuscitation solutions for the inpatient and ambulatory neonatal markets.

The Company acquired Essentialis, Inc., or Essentialis, through a merger, or the Merger, on March 7, 2017, pursuant to Agreement and Plan of Merger dated December 22, 2016. Essentialis’s efforts prior to the Merger were focused primarily on developing and testing product candidates that target the ATP-sensitive potassium channel, a metabolically regulated membrane protein whose modulation has the potential to impact a wide range of rare metabolic, cardiovascular, and CNS diseases. Essentialis has tested Diazoxide Choline Controlled Release Tablet, or DCCR, as a treatment for Prader-Willi Syndrome, or PWS, a complex metabolic/neurobehavioral disorder. DCCR has orphan designation for the treatment of PWS in the United States, or U.S., as well as in the European Union, or E.U. Consummation of the Merger was subject to various closing conditions, including the Company’s consummation of a financing of at least $8.0 million at, or substantially contemporaneous with, the closing of the Merger, which occurred on March 7, 2017 and the receipt of stockholder approval of the Merger at a special meeting of its stockholders, which was held on March 6, 2017.

Subsequent to the acquisition of Essentialis, the Company determined to divest, sell or otherwise dispose of the CoSense, NFI and Serenz businesses. Accordingly, and pursuant to ASC 205-20-45-10, any assets and liabilities related to the discontinued activities of CoSense, NFI and Serenz have been presented separately in the balance sheet as held for sale items, and the related operations reported herein for the CoSense, NFI and Serenz activities are reported as discontinued operations in the statements of operations.

The Company determined to divest, sell or otherwise dispose of the CoSense, NFI and Serenz businesses in order to focus on the development and commercialization of novel therapeutics for the treatment of rare diseases. The Company’s current research and development efforts are primarily focused on advancing its lead candidate, DCCR tablets for the treatment of PWS, into late-stage clinical development.

The Company sold its entire interest in NFI in a stock transaction that was completed on July 18, 2017, pursuant to a Stock Purchase Agreement dated July 18, 2017, or the NFI Purchase Agreement, entered into with Neoforce Holdings, Inc., a wholly-owned subsidiary of Flexicare Medical Limited, a privately-held United Kingdom company, for $720,000 and adjustments for inventory and the current cash balances held at NFI.

On December 4, 2017, Soleno, and Capnia, Inc., a Delaware corporation, or Capnia, entered into a joint venture with OptAsia Healthcare Limited, or OAHL. The purpose of the joint venture is to develop and commercialize medical monitors, including CoSense, that measure end-tidal carbon monoxide in breath to assist in the detection of excessive hemolysis in neonates, a condition in which red blood cells degrade rapidly and which can lead to adverse neurological outcomes.

The Company has previously charged to expense all previously-held assets related to its Serenz operations, and there are no remaining Serenz assets, liabilities or operations related to the Company’s previous Serenz-related business.