Overcrowding in healthcare environments (e.g., hospitals) has become a widely identified problem in today's healthcare. This research documents whether and how social crowding affects consumers' self-perceived health risks in healthcare environments and its downstream effect. One pilot study (secondary data analysis), seven laboratory experiments, and a field survey (Study 6) demonstrated that social crowding increased individuals' self-perceived health risks through a lack of control (Studies 1-6), thereby leading to overspending on the healthcare products (Study 5). Furthermore, the mediating process was moderated by choice and disease symptom severity (Studies 3 and 4). The findings of this research theoretically enrich our understanding of how social crowding interacts with individual disease symptoms and the services provided in the healthcare environment, and practically provide important implications for healthcare practitioners in managing consumers' health risks and consumption behavior.