v3.25.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2025
May 14, 2025
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Securities Act File Number 001-38899  
Entity Registrant Name Milestone Pharmaceuticals Inc.  
Entity Incorporation, State or Country Code A8  
Entity Tax Identification Number 00-0000000  
Entity Address, Address Line One 1111 Dr. Frederik-Philips Boulevard  
Entity Address, Address Line Two Suite 420  
Entity Address, City or Town Montréal  
Entity Address, State or Province QC  
Entity Address, Country CA  
Entity Address, Postal Zip Code H4M 2X6  
City Area Code 514  
Local Phone Number 336-0444  
Title of 12(b) Security Common Shares  
Trading Symbol MIST  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   53,464,273
Entity Central Index Key 0001408443  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Amendment Flag false