Oral Medication pills for type 2 diabetes are classed in several categories depending their on type. Each category of diabetes oral medication works differently.
1) Sulfonylureas.
This medication helps to lower blood sugar by getting the pancreas to release more insulin. There have been a few different brands of sulfonylureas produced over the years, however a lot of the older brands are no longer used due to their lesser potency and shorter action time when compared to the recent releases. These drugs can be effective in lowering a persons HbA1c by around 1%-2%.
2) Biguanides.
These pills help improve the ability of insulin to move glucose into the cells (especially muscle cells) and also helping to prevent the releasing of stored glucose form the liver. This class of medication should not be given to people with kidney or heart problems as there is added risk a severe build up of lactic acid in these patients. Biguanides can also help to decrease the HbA1c by 1%-2%. The most commonly administered drug for type 2 diabetes 'metformin' fits into this class of drugs.
3) Thiazolidinediones.
This category of diabetes drugs help improve insulin's effectiveness within the muscle and fat tissue. They work by lowering the amount of glucose that the liver can release and also encourage fat cells to be more sensitive to insulin. Like the previous two options, thiazolodinediones also help achieve a decrease in HbA1c of around 1%-2%. This type of drug can sometimes take a few weeks to be effective, and they should not generally be prescribed to people in heart failure.
4) Alpha-glucosidase inhibitors
These diabetes drugs block the enzymes that help to digest starches, thereby slowing the rise in blood glucose. They have a possible side effect of causing wind and/or diarrhea. Their effect on the Hb1Ac is around 0.5%-1%.
5) Meglitinides
These type 2 diabetes medicines have an effect on blood glucose levels by also helping the pancreas to release more insulin. The responsiveness of this class of drugs is known as glucose dependent, meaning they respond depending on the levels of glucose in the blood. This is different to the sulfonylureas group that cause insulin to be released regardless of the blood glucose levels, which can sometimes lead to hypoglycemia. (low blood sugars)