The participants who meet the eligibility criteria, will receive a single dose of placebo (an inactive substance that is compared with a drug to test whether the drug has a real effect in a clinical trial) and this will be followed by baseline 24 hour pharmacodynamic assessments. On the next morning participants will receive the first canagliflozin dose and will be discharged home to continue canagliflozin treatment for 13 additional days. There will be 2 treatment groups (8 participants in each): the first group will receive canagliflozin 100 mg daily, the second group will receive either canagliflozin 300 mg or canagliflozin 50 mg daily. The canagliflozin dose for the second treatment group will be determined after the sponsor has evaluated the results from the first 5 participants. On day 14 of treatment the participants will be admitted again for 24 hour pharmacokinetic and pharmacodynamics assessments. The participants will continue to take their normal dose and schedule of metformin during the entire study. The total duration of the study is approximately 50 days.