Unfortunately, nausea, stomach upset and diarrhea are common side effects of metformin/glucophage. It's not an allergic reaction though, and apparently the symptoms are transient, meaning the body adjusts and they resolve on their own over time. The usual recommendation is to start at a low dose and work up, and to take with food. There's no difference between the xr and the immediate release forms regarding the side effects
Apparently 1500mg per day is the MINIMUM effective dose, and may be up t 2550mg depending on response, ie .. blood sugar control and HbA1c (glycosylated hemoglobin, which indicates peak blood sugar levels over a period of 5 - 6 weeks). The glucophage can be used in combination with the glucotrol or other sulfonurea-type hypoglycemic drug until your blood sugars are under control.
Glucophage/metformin really would be the drug of choice, if you could somehow tolerate the side effects at the beginning. Maybe the dr. could prescribe an anti-nausea medication that you could take for the first few weeks, to get you over the "hump".
Glucotrol and other sulfonylureas lower your blood sugar by stimulating the pancreas to pump out more insulin. It's the extra insulin that causes increased fat storage, and also prevents fat from being lost. Plus over time, the cells become more and more resistant to the excessive insulin.
Metformin works by decreasing insulin resistance, so less insulin gets pumped into the blood. Less insulin means fat isn't being stored, and your body can actually lose fat. It also slows the absorption of glucose from the intestine, and it inhibits the liver from producing glucose (glycogen). It will even help to reduce cholesterol and triglyceride levels
.. I guess the unpleasant side effects are the trade off. As well, if you have existing kidney and/or liver disease, metformin may cause a toxic buildup of lactic acid in the blood, which can be fatal.
Here is an online version of the
patient information/package insert for metformin/glucophage.
Doreen