>10%: Gastrointestinal: Diarrhea (10% to 53%), nausea/vomiting (7% to 26%), flatulence (12%).
Neuromuscular and skeletal: Weakness (9%).
1% to 10%: Cardiovascular: Chest discomfort, flushing, palpitation.
Central nervous system: Headache (6%), chills, dizziness, lightheadedness.
Endocrine and metabolic: Hypoglycemia.
Gastrointestinal: Indigestion (7%), abdominal discomfort (6%), abdominal distention, abnormal stools, constipation, dyspepsia/heartburn, taste disorder.
Neuromuscular and skeletal: Myalgia.
Respiratory: Dyspnea, upper respiratory tract infection.
Miscellaneous: Decreased vitamin B12 levels (7%), increased diaphoresis, flu-like syndrome, nail disorder.
<1%: (Limited to important or life-threatening): Lactic acidosis, leukocytoclastic vasculitis, megaloblastic anemia, pneumonitis.