1. There are two main types of diabetes mellitus: type 1 characterized by a loss of pancreatic beta cells and absolute dependence on insulin; type 2 usually occurs in adults and is characterized by reduced response to insulin. 2. Common drug treatments for diabetes include insulin, sulfonylureas which stimulate insulin release, metformin which reduces glucose production and sensitivity, acarbose which slows carbohydrate absorption, and thiazolidinediones which sensitize tissues to insulin. 3. Newer injectable drugs pramlintide and exenatide mimic hormones that regulate insulin and glucagon secretion to control post-meal blood sugar levels but can cause side effects like nausea, vomiting and hypoglycemia.