Table 4. Adverse events.

Adverse events	Metformin, n (%)	Placebo, n (%)	P
Worst grade			0.001***
Grade 0	8 (17.8)	19 (43.2)
Grade 1	26 (57.8)	23 (52.3)
Grade 2	10 (22.2)	2 (4.7)
Grade 3	1 (2.2)	0 (0.0)
Abdominal pain	11 (24.4)	6 (13.6)	0.283
Nausea and vomiting	17 (37.8)	6 (13.6)	0.015*
Diarrhea	23 (51.1)	6 (13.6)	0.0003***
Flatulence/bloating	6 (13.3)	2 (4.5)	0.267
Anorexia	9 (20.0)	0 (0.0)	0.003**
Taste disturbance	3 (6.7)	2 (4.5)	1.000
Rash/itching	6 (13.3)	2 (4.5)	0.267
Renal dysfunction	1 (2.2)	0 (0.0)	1.000

NOTE: There were 28 unique preferred terms each recorded in at least one participant. The worst grade within an individual across all 28 terms was reported and compared using the Wilcoxon signed rank test. Eight of the 28 terms most likely to be related to metformin exposure are shown here. For these entries, the numbers of cases experiencing any grade (1–3) of a specific adverse event were recorded and compared using Fisher exact tests. For the purpose of adverse event reporting, all participants taking at least one dose of the trial medication were included (metformin n = 45, placebo n = 44). *, P ≤ 0.05; **, P ≤ 0.01; ***, P ≤ 0.001.