Oral diabetes medications, sometimes called diabetes tablets or oral glucose-lowering agents, help people manage blood glucose levels. They are commonly used to manage type 2 diabetes to improve insulin sensitivity, increase insulin production or reduce glucose production in the liver.
Oral medications are often used alongside healthy lifestyle changes such as balanced nutrition and physical activity.
Metformin is one of the most commonly prescribed oral medications for type 2 diabetes. Other medications may be used alone, in combination with metformin or alongside insulin depending on individual management needs.
What are oral diabetes medications?
Oral diabetes medications are tablets or capsules used to help lower blood glucose levels, particularly in people living with type 2 diabetes.
These medications work in different ways depending on:
- The type of medication
- Insulin production
- Insulin resistance
- Blood glucose patterns
- Other medical conditions
Oral medications are usually prescribed when:
- Healthy lifestyle changes alone are not enough
- Blood glucose levels remain above target range
- Additional support is needed to reduce the risk of diabetes complications
Some people with diabetes take a single medication, while others require combination therapy involving two or more medications.
Who may need oral diabetes medications?
People living with type 2 diabetes mainly use oral diabetes medication when healthy eating, physical activity and weight management are not enough to keep blood glucose within the target range.
Some people with gestational diabetes may need oral medication if healthy nutrition, physical activity and other lifestyle changes are not enough to manage blood glucose levels during pregnancy.
People with type 1 diabetes require insulin therapy. Oral diabetes medications are not used as a substitute for insulin, although in some cases they may be prescribed alongside insulin to manage the condition.
How oral diabetes medications work
Oral agents increase insulin secretion from the pancreas and improve insulin sensitivity. Often the first-line treatment for type 2 diabetes, they are easy to take, help control blood glucose levels and reduce the risk of diabetes complications. Choosing the right oral agent depends on several factors, including the severity of diabetes, the intended use and other medical conditions.
Several classes of oral agents are available, so working with a healthcare professional is important when choosing the right oral glucose-lowering agent for type 2 diabetes management.
Unfortunately, not all oral agents are suitable for all people with diabetes, and healthcare professionals need to customise the treatment according to the needs of the person with diabetes. Knowing the facts can help when choosing an oral agent for a person’s management plan.
Different oral diabetes medications help lower blood glucose levels in different ways.
Some medications:
- Improve insulin sensitivity
- Reduce glucose production in the liver
- Increase insulin release from the pancreas
- Slow carbohydrate absorption
- Improve glucose removal from the bloodstream
Healthcare professionals prescribe medications based on:
- Blood glucose levels
- Diabetes severity
- Kidney and cardiovascular health
- Other medical conditions
- Risk of side effects
- Individual treatment goals
Management plans may change over time depending on how diabetes progresses and how well blood glucose levels are managed.
Types of oral diabetes medications
Metformin is often part of first line treatment for type 2 diabetes and one of the most widely used diabetes medications globally.
It helps lower blood glucose by:
- Reducing glucose production in the liver
- Improving insulin sensitivity
- Helping the body use insulin more effectively
Metformin is mainly prescribed because:
- It is generally effective
- It has a low risk of hypoglycaemia (low blood glucose) when used alone
- It is widely available
- It can support modest weight management
It may be used on its own, alongside other oral medications or together with insulin therapy.
Metformin may not be appropriate for everyone, particularly people with:
- Severe kidney disease
- Certain liver conditions
- Severe dehydration
- Some medical complications
Sulfonylureas help the pancreas release more insulin to lower blood glucose levels.
These medications can be effective for some people with type 2 diabetes but can increase the risk of hypoglycaemia and weight gain.
Thiazolidinediones, also called glitazones, help improve insulin sensitivity, allowing the body to use insulin more effectively. Pioglitazone is an example of this type of medicine. Healthcare professionals sometimes prescribe it for people with type 2 diabetes, depending on their individual management needs and overall health.
Pioglitazone is not suitable for everyone. It may cause weight gain or fluid retention and is not recommended for people with heart failure. Management decisions should always be guided by a healthcare professional.
Alpha-glucosidase inhibitors slow carbohydrate digestion and reduce how quickly glucose enters the bloodstream after eating.
These medications may help reduce blood glucose spikes after meals.
Incretin-based therapies help regulate insulin release and reduce glucose production. They can also support weight management in some people with type 2 diabetes.
Some incretin-based medications are taken orally, while others are injectable treatments.
The two main types of incretin-based therapies are DPP-4 inhibitors and GLP-1 receptor agonists.
DPP-4 inhibitors, also called gliptins, are oral medicines sometimes used by people with type 2 diabetes. They help the body release more insulin when needed and reduce the amount of glucose released into the blood. They do not usually cause hypoglycaemia when taken alone and usually do not cause weight gain or weight loss.
GLP-1 receptor agonists are sometimes used to manage type 2 diabetes. They help lower blood glucose by supporting insulin release when needed and slowing digestion after meals. Some may also support weight loss. Most GLP-1 receptor agonists are injectable, although semaglutide is available as both an injection and a tablet for type 2 diabetes.
SGLT2 inhibitors are medicines that help the kidneys remove excess glucose from the blood through urine. They are commonly used to treat type 2 diabetes and can also help protect the heart and kidneys in some people, including those with heart failure or chronic kidney disease.
Oral medication and insulin therapy
Some people with diabetes may use oral medications alongside insulin therapy.
Combination treatment can help:
- Improve blood glucose control
- Reduce insulin requirements
- Support personalised management plans
People with type 2 diabetes may:
- Start treatment with oral medication
- Later require insulin
- Use both insulin and oral medication together
Monitoring blood glucose while taking oral medication
People taking oral diabetes medications may still need to measure their blood glucose regularly.
Blood glucose monitoring helps:
- Assess how well treatment is working
- Detect high or low blood glucose levels
- Support medication adjustments
- Reduce the risk of complications
Monitoring may involve finger-prick blood glucose testing or Continuous Glucose Monitoring (CGM).
Possible side effects and management considerations
Potential side effects should be considered when developing an oral agent management plan. Sulfonylureas, for example, may cause hypoglycaemia (low blood glucose) in some people with diabetes and may not be suitable for those with kidney or liver disease. Biguanides, on the other hand, may cause gastrointestinal side effects, such as diarrhoea and nausea.
Another factor is how oral agents interact with diabetes complications to prioritise management and reduce risks. This can be done by testing blood glucose levels several times daily or using a continuous glucose monitoring device to track levels over time.
In addition to monitoring blood glucose levels, several other considerations must be made when taking oral agents for the best possible outcomes. These can include:
- Following a healthy diet.
- Exercising regularly.
- Managing other medical conditions, such as high blood pressure and cholesterol.
Lifestyle and oral diabetes medication
Oral medications work best when combined with healthy lifestyle habits, including:
- Healthy nutrition
- Regular physical activity
- Maintaining a healthy body weight
- Managing stress
- Avoiding smoking
Healthy lifestyle support remains an important part of diabetes management, even when medication is required.
Global access to oral diabetes medications
Access to oral diabetes medication remains unequal worldwide.
Many people face barriers including:
- High medication costs
- Limited healthcare access
- Delayed diagnosis
- Shortages of essential medicines
- Lack of diabetes education
Improving access to affordable diabetes medication is important to reduce the risk of complications and improve diabetes outcomes.
This challenge is particularly significant in low- and middle-income countries where healthcare infrastructure and medication availability can be limited.
Future developments in oral diabetes medications
Research into diabetes medications continues to evolve, with newer treatments aiming to:
- Improve blood glucose management
- Reduce cardiovascular risk
- Support weight management
- Simplify treatment routines
- Improve quality of life
These advances aim to improve long-term outcomes for people living with diabetes worldwide.
Related resources
Online course
Type 2 diabetes - Oral agents fact-checking
A free IDF School of Diabetes online course for healthcare professionals that provides a customised set of modules on the management of type 2 diabetes using oral glucose-lowering agents.
link to https://www.idfdiabeteschool.org/premium-courses/t2dm-oral-agents-fact-checking
Guideline
IDF Clinical Practice Recommendations for Managing Type 2 Diabetes in Primary Care
Published in 2017, these Clinical Practice Recommendations for healthcare professionals summarise current evidence around optimal management of people with type 2 diabetes.
T2D-primary-care.pdf
pdf
3MB
