Other than the smoking , which I don ' t have experience with , I don ' t see anything there that would obviously be the culprit . I think your best bet is to discuss it with your doctor , though there ' s no guarantee that they ' ll know either . Some people are just more resistant to certain drugs than others . One thing that did cross my mind have you had your thyroid levels checked ? If thyroid is low , that could mask the effects of the amphetamine . Regardless I wouldn ' t worry about the secondary effects of the drug . They ' re not what you ' re looking for anyway . How is your ability to concentrate ? <| sep |> Vinktar ' s removed from the game . <| sep |> Can ' t tell if 4 inches or 6 inches . <| sep |> 1 pound 1 dollar 1 like 1 amen