u/Educational-Fox7376

If i have 15mg of reta, how much bac water to add, and how much to take from the stringe before injecting if i want 1mg and if i want to upper the dose after a week by 0.5 do i add anymore bac water and how much do i take from the syringe, i need someone to explain how this works cuz im so lost and idk what units are

Can someone explain what are units and how much bac water to add and how much to take for a starter cuz im lost yall