v3.19.3
Document And Entity Information - shares
9 Months Ended
Sep. 30, 2019
Oct. 28, 2019
Document Information [Line Items]    
Entity Registrant Name ACELRX PHARMACEUTICALS INC  
Entity Central Index Key 0001427925  
Trading Symbol acrx  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Entity Current Reporting Status Yes  
Entity Emerging Growth Company false  
Entity Small Business true  
Entity Common Stock, Shares Outstanding (in shares)   79,573,001
Entity Shell Company false  
Document Type 10-Q  
Document Period End Date Sep. 30, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Title of 12(b) Security Common Stock, $0.001 par value