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I would like to suggest Brahmi ghrita (Brahmi, Vacha, Kushta, Shankhapushpi) 1 teaspoon before food with warm milk at night. Do regular head massage with Brahmi Taila or apply little Brahmi taila (Brahmi, Amalaki, Tila taila) daily on his crown. Do regular body oil massage with sesame oil. Make sure to include milk, ghee, and almonds in his diet. Put him in meditation and pranayama classes. Do all this for a month and revert back. I do not want to comment on Vyvanse (Lisdexamfetamine). You need to consult his pediatrician about it.