Note 1 - Organization and Description of Business	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization and Description of Business Diffusion Pharmaceuticals Inc. ("the Company"), a Delaware corporation, is a biopharmaceutical company developing novel therapies that enhance the body’s ability to deliver oxygen to areas where it is needed most. The Company’s lead product candidate, TSC, is being developed to enhance the diffusion of oxygen to tissues with low oxygen levels, also known as hypoxia, a serious complication of many of medicine’s most intractable and difficult-to-treat conditions. In November 2021, based on the preclinical and clinical data accumulated to date and the significant unmet medical need, the Company announced that its near-term focus will be the design and execution of a clinical program to support the use of intravenously administered TSC as an adjunctive treatment for hypoxic solid tumors.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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