Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 20, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Entity Registrant Name	OPEXA THERAPEUTICS, INC.
Entity Central Index Key	0001069308
Document Type	10-K
Document Period End Date	Dec. 31, 2014
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Is Entity a Well-known Seasoned Issuer?	No
Is Entity a Voluntary Filer?	No
Is Entity's Reporting Status Current?	Yes
Entity Filer Category	Smaller Reporting Company
Entity Public Float			$ 43,709,741
Entity Common Stock, Shares Outstanding		28,234,751
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2014