Glucophage Adverse Reactions

The undesirable effects listed as follows may occur under treatment with metformin HCl.
Frequencies are defined as follows: Very common (≥1/10); common (≥1/100, <1/10); uncommon (≥1/1000, <1/100); rare (≥1/10,000, <1/1000); very rare (<1/10,000); not known (cannot be estimated from the available data).
Nervous System Disorders: Common: Taste disturbance.
Gastrointestinal Disorders: Very Common: Gastrointestinal disorders eg, nausea, vomiting, diarrhea, abdominal pain and loss of appetite. These undesirable effects occur most frequently during initiation of therapy and resolve spontaneously in most cases. To prevent them, it is recommended that metformin hydrochloride be taken in 2 or 3 daily doses during or after meals. A slow increase of the dose may also improve gastrointestinal tolerability.
Skin and Subcutaneous Tissue Disorders: Very Rare: Skin reactions eg, erythema, pruritus, urticaria.
Metabolism and Nutrition Disorders: Very Rare: Lactic acidosis. Decrease of vitamin B12 absorption with decrease of serum levels during long-term use of metformin hydrochloride. Consideration of such aetiology is recommended if a patient presents with megaloblastic anaemia.
Hepatobiliary Disorders: Isolated reports of liver function tests abnormalities or hepatitis resolving upon metformin hydrochloride discontinuation.
Children and Adolescents: In published and post-marketing data and in controlled clinical studies in a limited pediatric population 10-16 years treated for 1 year, adverse event reporting was similar in nature and severity to that reported in adults.