Taking Your Medicine – Oral Hypoglycemic Agents (OHA)

In general, the accepted treatment for Type 1 diabetes (T1D) is insulin. For Type 2 diabetes (T2D), there are other forms of treatment for the management of the disease. Among the types available are Oral Hypoglycemic Agents (OHA).

What are OHA?

OHAs are also defined as Oral Anti-Diabetic agents (OAD’s). These medications are intended to help achieve the goal of insulin normalization. They involve one of several actions.

  • Stimulate insulin secretion
  • Reduce production of glucose produced in the liver
  • Digestion and the assimilation of intestinal carbohydrates can be delayed
  • Improved insulin sensitivity

The drugs are described as heterogeneous in regards to their safety profile, means of action and acceptability.

Types of OHAs

There are many different types of OHAs. The major classes consist of the following:

  • Sulphonylureas and swift-acting secretagogues  – These stimulate the secretion of insulin
  • Biguanides – These drugs reduce hepatic glucose production and improve insulin sensitivity
  • Alpha-glucosidase inhibitors – These drugs delay digestion and absorption of intestinal carbohydrate
  • Thiazolidinediones – These drugs improve insulin action[2]

Because the medications that fall within the umbrella classification of OHA have several different effects, they are often employed in various combinations. The intent is to achieve maximum blood glucose control. Working in certain combinations the drugs can reduce the body’s demand for food, increase the quantity of insulin produced, or amplify the effect of the insulin that is on hand. In this way, the combinations can address numerous “targets.”

Your medical team will help you decide whether your diabetes requires the assistance of any of these types of OHA medications, alone or in combination.

OHA – Who should and Who Should Not Use It

There are definitely individuals who can benefit from taking OHA medications. There are also those who should not take these drugs. Those who should not take the drugs that comprise this group include:

  • Those individuals who have T1D
  • Those who cannot tolerate the side effects

Those who may employ OHA medications include:

  • Certain individuals with T2D
  • Those for whom the medications are a useful and beneficial addition to other forms of treatment
  • Those cases where the drugs can be used combination and coordination with insulin to benefit the diabetic

When should OHA be used?

When should OHA be used in diabetes treatment? The simple answer to this question is that OHA medications should be used when appropriate for the situation. This requires understanding what each type or class of drug within the category OHA can is able to accomplish for the individual patient. These medications, however, tend to be called into action when the following are insufficient in those with T2D to control or fail to reduce blood sugar levels so it falls within the proper range:

  • Weight reduction
  • Diet control
  • Increase in exercise

It is also a part of a regimen in which the diabetic state is mild but must be altered to prevent further entanglement.

How to Use OHA

The implementation of OHA drugs should be done gradually. The initial dose should be low. It should then be titrated up in accordance with glycemic response. The response is judged by the measurement of the concentration of glycosylated hemoglobin (HbA1c).  The medications are also adjusted for patients based on the results of the self monitoring of glucose.

Of primary importance in the administering of this drug is the individual’s own needs. As a result, the OHA class of drugs must be tailored to fit each patient’s requirements. The initial administration is low, closely monitored and based on both the doctor’s information and the input of the patient. The dosage is then increased gradually in accordance to the patient’s reaction. This, of course, will vary in response to the known characteristics of the drug. For instance, in the case of the OHA sulphonylureas, the best level for the maximal glucose-lowering action is achieved at lower doses rather than the higher ones recommended by the manufacturer.

Implementation of combinations of drugs also requires diligent consideration. While you can achieve beneficial results from combining some, this is not always the case. While some pills are produced separately, you can also take 2 different medications combined into a single pill.[3] It is common and logical to combine a secretagogue and a biguanide or a secretagogue with a thiazolidinedione. This is a practice widely used in the US and many countries around the world.


Taking insulin is the only solution to helping you control your T1D. In the case of T2D, however, there is always the chance you may be able to control your diabetes with lifestyle changes and oral hypoglycemic agents. This type of mediation can be taken alone or in combination.

OHA drugs are intended to accomplish a variety of different, but often interrelated actions. They are often instituted when such things as weight reduction, exercise and diet control fail or simply are not enough. Whenever they are applied, they are done so gradually. The medical team also ensures that OHA medications are tailored to suit each individual’s needs.

If you believe you could benefit from using OHAs and that it will help you control your blood sugar levels and, therefore, your diabetes, go online and explore the uses, benefits and issues surrounding the various medications, including credited government sources.[5] After you have sufficient evidence and information, arrange to discuss them with your personal doctor and/or medical team. With their input, you will be able to learn whether Oral Hypoglycemic Agents (OHA) are right for you.


[1] Perin, PC; and Fornengo, P. (2011). “New Oral Antidiabetic Agents” Internal and Emergency Medicine, 6 (Supplement 1):135-138.

[2] Krentz, AJ; and Bailey, CJ. (2005). “Oral Antidiabetic Agents: Current Role in Type 2 Diabetes Mellitus.”  Drugs, 65(3): 385-411(27).

[3] Warshaw, HS; and Pape, J (2009). Real-Life Guide To Diabetes. Alexandria, VA: ADA.

[4] Krentz and Baily (2005).

[5] Department of Health and Services (2011). “Diabetes Medications Supplement.” Retrieved from http://ndep.nih.gov/media/Drug_tables_supplement.pdf.

This article was originally published July 12, 2012 and last revision and update of it was 9/10/2015.