- Women report more adverse drug reactions (ADRs) to metformin shortly after initiation vs men and reduce prescribed doses after several months.
Why this matters
- Metformin is first-line treatment in type 2 diabetes, but ADRs are common.
- From Dutch pharmacovigilance database, 1712 patients were asked to complete web-based questionnaires at 2 and 6 weeks and 3, 6, 9, and 12 months after metformin initiation.
- Funding: ZonMW—The Netherlands Organization for Health Research and Development; European Union.
- During follow-up, 46% of women reported ≥1 ADR, compared with 37% of men.
- Most common ADRs were diarrhea, nausea, abdominal discomfort, flatulence, headache, and fatigue.
- 34% of women and 25% of men reported ADRs in the first 2 weeks (P<.001>
- 37% of women vs 28% of men reported ADRs at 6 weeks (P=.001).
- From 2 weeks to 12 months, the average overall metformin dose increased slightly more for men (830-1161 mg) than women (809-1034 mg).
- Average doses were higher for men than women throughout, but significantly so only at 9 months (P<.01>
- Only 28% completed all 6 assessments.
- No information about other patient characteristics (e.g., weight, diabetes duration, kidney function).
- Questionnaire responders may not represent all metformin users.