RIOMET SIDE EFFECTS
- Generic Name: metformin hcl
- Brand Name: Riomet
- Drug Class: Antidiabetics, Biguanides
SIDE EFFECTS
The following adverse reactions are also discussed elsewhere in the labeling:
- Lactic Acidosis
- Vitamin B12 Deficiency
- Hypoglycemia
Clinical Studies Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
In a U.S. clinical trial of metformin HCl tablets in patients with type 2 diabetes mellitus, a total of 141 patients received metformin HCl tablets up to 2,550 mg per day. Adverse reactions reported in greater than 5% of patients treated with metformin HCl tablets and that were more common than in placebo-treated patients, are listed in Table 1.
Table 1: Adverse Reactions from a Clinical Trial of Metformin HCl Tablets Occurring >5% and More Common than Placebo in Patients with Type 2 Diabetes Mellitus
| Metformin HCl Tablets (n =141) |
Placebo (n = 145) |
|
| Diarrhea | 53% | 12% |
| Nausea/V omiting | 26% | 8% |
| Flatulence | 12% | 6% |
| Asthenia | 9% | 6% |
| Indigestion | 7% | 4% |
| Abdominal Discomfort | 6% | 5% |
| Headache | 6% | 5% |
Diarrhea led to discontinuation of metformin HCl tablets in 6% of patients. Additionally, the following adverse reactions were reported in ≥ 1% to ≤ 5% of patients treated with metformin HCl tablets and were more commonly reported than placebo: abnormal stools, hypoglycemia, myalgia, lightheaded, dyspnea, nail disorder, rash, sweating increased, taste disorder, chest discomfort, chills, flu syndrome, flushing, palpitation.
Pediatric Patients
In clinical trials with metformin HCl tablets in pediatric patients with type 2 diabetes mellitus, the profile of adverse reactions was similar to that observed in adults.
Laboratory Tests
Vitamin B12 Concentrations
In clinical trials of 29-week duration with metformin HCl tablets, a decrease to subnormal levels of previously normal serum vitamin B12 levels was observed in approximately 7% of patients.
Postmarketing Experience
The following adverse reactions have been identified during post approval use of metformin. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Cholestatic, hepatocellular, and mixed hepatocellular liver injury have been reported with postmarketing use of metformin.
SRC: NLM .