Drinking alcohol
Gudbergsen H, Henriksen M, Waehrens EE, Overgaard A, Bliddal H, Christensen R, Boesen MP, Knop FKK, Astrup A, Rasmussen MU, Bartholdy C, Daugaard C, Bartels EM, Ellegaard K, Heitmann BL, Kristensen LE (2019) Effect of liraglutide on body weight and pain in patients with overweight and knee osteoarthritis: protocol for a randomised, double-blind, placebo-controlled, parallel-group, single-centre trial
The short answer is Until you are satisfied with improvements in communication and the treatment no longer seems to be helping. Another useful response is, Consider discontinuing mB12 when stimming becomes more disruptive than language acquisition. I find it peculiar that parents pose this question at all
PubMed Vasile A, Goldberg R, Kornberg B