Aims. The present study is aimed at exploring the effects of sodium-glucose cotransporter-2 (SGLT-2) inhibitors on weight in type 2 diabetes mellitus (T2DM) and therapeutic regimen recommendations. Methods. 20,019 patients with T2DM were enrolled. The maximal effect (
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max
) models, whose evaluation index was change rate of body weight from baseline value, were used to analyze data using nonlinear mixed effect modeling (NONMEM). Results. For SGLT-2 inhibitors, canagliflozin, empagliflozin, ertugliflozin, ipragliflozin, luseogliflozin and tofogliflozin, the
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max
, and treatment duration to reach half of the maximal effects (ET50) were -3.72% and 3.35 weeks, -5.59% and 16.8 weeks, -2.84% and 3.42 weeks, -3.43% and 3.09 weeks, -3.04% and 4.38 weeks, and -2.45% and 3.16 weeks, respectively. In addition, for T2DM patients, 100 mg/day canagliflozin needs to be taken 13.4 weeks for the plateau of effect on weight; 10 mg/day empagliflozin needs to be taken 67.2 weeks for the plateau of effect on weight; 5 mg/day ertugliflozin needs to be taken 13.68 weeks for the plateau of effect on weight; 50 mg/day ipragliflozin needs to be taken 12.36 weeks for the plateau of effect on weight; 2.5 mg/day luseogliflozin needs to be taken 17.52 weeks for the plateau of effect on weight; 20 mg/day tofogliflozin needs to be taken 12.64 weeks for the plateau of effect on weight. Conclusions. This was the first study to explore effects of SGLT-2 inhibitors on weight in T2DM; meanwhile, the optimum dosages and treatment durations on weight from canagliflozin, empagliflozin, ertugliflozin, ipragliflozin, luseogliflozin, and tofogliflozin were recommended, respectively.