Welcome to HW. Hope we can help you find the correct answer to your problem. Many people experience nausea and diarrhea on metformin and the best ways to deal with this have shown to be
1) Take the med with food
2) Dramatically lower the intake of sweet or starchy carbs in your food plan.
Because one of the main actions of metformin is to decrease intestinal absorption of glucose, the excess starches that have been turned into glucose by your gastric juices tend to "percolate" or ferment a bit in your gut. This leads to gas bubbles, gastric discomfort and nausea as well as loose stools. By increasing your vegetable servings to two or three and decreasing your intake of breads, grains and baked goods at meals you should see a dramatic change in your tummy climate. Limiting your fruits to one or two a day will help also.
Your body should acclimate to this med over time. Metformin is one of the safest diabetes drugs around. This med decreases your liver glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity in your cells, much like exercise does. Unlike sulfonylureas, metformin doesn't cause a lot of low blood sugar episodes, either. By changing the way you eat you can actually help the med work better and delay the onset of diabetic complications.
Moderator for Fibromyalgia and Diabetes