Why many people on amphetamine salts and kanna feel like they need higher initial doses

https://www.tool-bookmarks.win/1-tried-kanna-capsules-last-week-felt-a-subtle-mood-lift-after-about-an-hour-took-it-on-an-empty-stomach-like-some-recommend-anyone-else-notice-stronger-effects-with-tea-instead-curious-about-dosing-times

People who take prescription amphetamine salts and also try kanna (Sceletium tortuosum) often report surprising early experiences: the stimulant feels muted or the kanna produces little effect until they bump up the dose