Professor Mark Bullimore of the University of Houston, Texas USA, tells us more on the complex topic of 0.01% atropine, including its stability as a compound, and takes us on a short journey through chemistry explaining how current studies are using novel formulations to address this issue. Have you heard of ‘heavy water’? I hadn’t, until now! Mark advocates for you to ‘be the doctor’, using the side effects as a gauge of drug efficacy, and even suggests a novel clinical approach in practice to determine the individual patient’s response and tolerance. We also discuss the mismatch (or otherwise) of refractive and axial length control results in atropine studies which don’t appear to be the case in studies of optical interventions, along with communicating the ‘why’ of myopia management through the dioptric effect of control.