Metformin HCl ER doesn't rapidly bring down blood sugar, according to WebMD. Rather, it decreases the amount of sugar made by the liver and the amount of sugar absorbed by the stomach and intestines, and it makes the body more sensitive to the insulin the body naturally produces.
Metformin extended-release is indicated for the treatment of type 2 diabetes along with diet and exercise, explains WebMD. It is also used in conjunction with lifestyle modifications to help prevent diabetes in people at high risk for the disease, as well as for women with polycystic ovarian syndrome.
The most common side effects of Metformin extended-release include indigestion, nausea and vomiting, loose stools and gas, taste changes and headaches, notes Drugs.com. Serious side effects warranting immediate medical attention include systemic allergic reaction, chest pain, dizziness or light headedness, breathing difficulties and unusual tiredness, weakness and drowsiness. Flu-like symptoms, muscle pain or weakness and irregular heartbeat also require rapid medical treatment.
Metformin carries a warning stating that it can cause a life-threatening condition called lactic acidosis, cautions MedicineNet.com. Those with a history of kidney or liver disease, poor circulation, serious infection, recent surgery and dehydration are at greatest risk. Others at risk are those with a history of heavy drinking and those who have undergone imaging studies that required an iodine-based contrast agent.