One drop per day of low-dose atropine (0.01%) has been shown to be effective in limiting the progression of myopia in several large clinical trials. At this dose atropine is prescribed “off label.”

https://www.aao.org/eyenet/article/how-to-use-low-dose-atropine-to-slow-myopic-progre

Low-dose atropine drops need to be used every day for years to continue curbing the progression of myopia; otherwise, the condition can come back.