More than 50 companies with ambitions to bring psychedelics to market have gone public since early 2020—a clear sign that mind-altering substances once relegated to college dorm rooms and underground nightclubs are gaining mainstream acceptance.

But the legal chiefs and other executives behind those companies—which are pursuing treatments for a range of mental health disorders, from addiction and depression to anxiety and PTSD—say they continue to battle stigmas and misconceptions that threaten to limit access to capital and hold back growth.