Calls to address crack-cocaine use in Brazil among homeless and street-frequenting populations who are in urgent need of health services have questioned the capacity of the Brazilian Unified Health System to attend to the nation’s most marginalized citizens. In recent years, Brazil has launched several actions to escalate care for substance users, yet many obstacles hindering accessibility and effectiveness of services remain. Paradoxically, these actions have been implemented in the context of a growing economic crisis, and expanding services for a population of poor and stigmatized substance users while cutting other government programs tends to elicit harsh criticism from citizens. In consequence of such prospects, this commentary aims to discuss barriers marginalized substance users face in accessing health services that are at risk of worsening with government cutbacks. Using Rio de Janeiro as an example, we explore two primary issues: the resource-strained, under-staffed and decentralized nature of the Brazilian Unified Health System and the pervading stigma that bars vulnerable citizens from official structures and services. Abandoning initiated government efforts to increase access to health services would risk maintaining vulnerable citizens at the margins of public structures, inhibiting the opportunity to offer this population humane and urgently needed treatment and care.