it was never mandated which brand/type I could buy I'm sure regulations vary by country, and probably? by state. In Oregon a contact lens prescription is for a

it was never mandated which brand/type I could buy I'm sure regulations vary by country, and probably? by state. In Oregon a contact lens prescription is for an exact brand and type of lens. That makes sense to me, because different lenses have different oxygen permeability (and probably other differences as well). When my daughter's doctor changed her brand, he wanted her to come back in for another visit to confirm they were tolerated equally well. And this was at an HMO type organization (Kaiser Permanente). They don't get paid per office visit, so they're not incentivized to bring you back unnecessarily. (I really like that aspect of KP).