The Americas are facing a significant burden of mental health conditions. The Pan American Health Organisation's regional Strategy for Improving Mental Health and Suicide Prevention is an important milestone in tackling this challenge. However, absence of any focus on gambling as a potential risk to the health and wellbeing represents a serious omission in the Strategy. In this viewpoint, we review existing scholarship demonstrating unequivocal links between gambling and a variety of mental health conditions and related harms. This is followed by an empirically-grounded discussion of how commercial gambling has recently rapidly expanded across the region and how the risks of this expansion have not been sufficiently considered at the policy level. We then present emerging regional evidence of the negative mental health impacts of gambling expansion. The review concludes by proposing possible policy actions to improve control over the gambling industry and reduce ensuing harms on mental health and wellbeing in the region, with a focus on PAHO's remit.