Quarterly report pursuant to Section 13 or 15(d)

Document And Entity Information

Document And Entity Information - shares
6 Months Ended
Mar. 31, 2021
May 05, 2021
Document And Entity Information    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2021  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q2  
Entity Registrant Name Arch Therapeutics, Inc.  
Title of 12(b) Security None  
Entity Central Index Key 0001537561  
Current Fiscal Year End Date --09-30  
Entity Current Reporting Status Yes  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   236,719,770
Entity Shell Company false  
Entity Emerging Growth Company false  
Entity Small Business true  
Entity Interactive Data Current Yes  
No Trading Symbol Flag true