The provincial Worker’s Compensation Boards (WCB) and The Workplace Safety and Insurance Board (WSIB, in Ontario) provide disability benefits to injured workers, which can include prescription drugs.
Each of these provincial organizations has specific processes for approving and covering the cost of appropriate medications. The link below will take you to a page which lists the individual WCBs and has their contact information and a link to their website. You can get information on coverage of specific medications by contacting your provincial WCB.
Links to WCBs / WSIBWorkplace Safety and Insurance Board website