I do agree there are limits to mg/kg scaling. Mg/kg is correcting for the volume in your body that the drug dissolves into, with the idea that people will get similar blood (and then brain) concentrations. However, this volume doesn’t scale with weight perfectly because peoples’ bodies are different on the high and low ends of weight. So I would personally suggest mg/kg up to a maximum of 120 mg. I don’t have strong evidence for a minimal dose from my studies, but if forced to choose I might use a minimum dose of 75mg.