Online Medical Teams (OMTs) are gaining widespread popularity as a new mode in Online Health Communities (OHCs), providing patients with comprehensive treatment and guidance. However, scant empirical literature examines the impact of multiple physician engagement on team efficiency in OHCs. In this paper, we fill this gap by exploring the effects of physician collaboration on consultation efficiency in OMTs. Specifically, we collect data from Haodf spanning 2017 to 2023 and employ a difference-in-differences approach. Our findings reveal that physician collaboration in OMTs reduces consultation efficiency. Based on the previous literature, we propose two potential underlying mechanisms, i.e., free-riding and cognitive-load effect, driving this effect. Our further analyses show that the cognitive-load effect significantly contributes to the decline in team efficiency, while there is no evidence to support the free-riding effect. In addition, the moderating roles of patient gender and physician experience demonstrate heterogeneity. Specifically, male patients and more experienced physicians mitigate the negative impact of physician collaboration on consultation efficiency. This study offers valuable theoretical insights for academic research and practical implications for the online healthcare industry.