Diabetes is a condition characterized by high levels of glucose in the blood. Type I diabetes, also called juvenile diabetes, requires injectable insulin; Type II diabetes might be controlled with either oral or injectable medication. There are a number of medications available that work in different ways, but the goal for all is to decrease high levels of blood glucose.
Oral Medications
Oral medication for diabetes is used by people with adult onset, or type II, diabetes. There are six types of oral medication in use, according to the American Diabetes Association. Two types, sulfonylureas and meglitinides, stimulate the release of insulin from beta cells in the pancreas. Sulfonylureas include Diabenese, Micronase, Glucotrol, Amaryl, Diabeta and Glynase. Meglitinides include Prandin and Starlix.
The other types of oral medication--biguanides, thiazolidinediones, alpha-glucosidase inhibitors and DPP-4 inhibitors--work in other ways.
Biguanides, such as Glucophage, decrease the amount of glucose produced by the liver. Thiazolidinediones, including Avandia and Actos, also decrease the amount of glucose produced by the liver and help insulin work better in muscle and fat. Alpha-glucosidase inhibitors, such as Glyset and Precose, block the breakdown of starches and some sugars in the intestine. Januvia and Onglyza are DPP-4 inhibitors; they prevent the breakdown of GLP-1, which reduces blood glucose.
Insulin
All type I diabetics and some type II diabetics must take insulin, an injectable protein. Either not enough insulin is being produced, as in the case of type I diabetics, or insulin is not being properly broken down, as with type II diabetics. Because insulin is a protein, it must be injected; if it were taken orally, it would be broken down in the stomach and not be absorbed properly.
Insulin comes in several forms: rapid-acting , short-acting, intermediate-acting and long-acting. The four types have different onset and duration intervals. Rapid-acting, for example, works within 5 minutes, peaks in 1 hour and continues to work for two to four hours, according to the American Diabetes Association. By contrast, long-lasting insulin reaches the blood stream within six to 10 hours and is usually effective for 20 to 24 hours. Diabetics might use more than one type of insulin. All insulin in the United States is synthetic, which means it's produced in the laboratory rather than coming from animal protein.
Other Injected Medication
One other injectable medication is used for type II diabetics, according to the Mayo Clinic. Byetta is a GLP-1 agonist, a drug that mimics the action of GLP-1, according to the Diabetes Network.
