Ryan and Savulescu argue that prescribing Glucagon-like peptide-1 receptor agonists (GLP-1) for weight loss is ethically justified on grounds of autonomy, health benefit and harm reduction. This response argues that emerging evidence on treatment durability and current prescribing patterns complicates that conclusion. Evidence suggests that weight loss is frequently reversed after treatment cessation, implying that meaningful benefit may depend on long-term use. This has implications for informed consent and distributive justice. If sustained benefit requires continued treatment, access to ongoing therapy becomes central. In the UK, increasing private prescribing risks a two-tier system in which those with greater financial resources can maintain benefit while others cannot. Ethical prescribing therefore requires a considered approach to counselling and attention to equitable long-term access.