Interactive laboratory class (ILC) is a two-way communication teaching method that encourages students to correlate laboratory findings with materials from lectures. In Thai medical education, active learning methods are uncommon. This paper aims to establish 1) if ILCs would effectively promote physiology learning; 2) if effectiveness would be found in both previously academically high-performing and low-performing students; and 3) the acceptability of ILCs to Thai medical students as a novel learning method. Two hundred seventy-eight second-year medical students were recruited to this study. We conducted three ILC sessions, which followed corresponding lectures. We carried out multiple-choice pre- and post-ILC assessments of knowledge and compared by repeated-measures ANOVA and unpaired t-test. Subgroup analysis was performed to compare high-performance (HighP) and low-performance (LowP) students. After the ILCs, participants self-rated their knowledge and satisfaction. Post-ILC test scores increased significantly compared with pre-ILC test scores in all three sessions. Mean scores of each post-ILC test increased significantly from pre-ILC test in both LowP and HighP groups. More students self-reported a "very high" and "high" level of knowledge after ILCs. Most students agreed that ILCs provided more discussion opportunity, motivated their learning, and made lessons more enjoyable. As an adjunct to lectures, ILCs can enhance knowledge in medical students, regardless of previous academic performance. Students perceived ILC as useful and acceptable. This study supports the active learning methods in physiology education, regardless of cultural context.