What is GLP-1 and how does it work
Glucagon-like peptide 1 (GLP-1) is a naturally occurring hormone in the body. Although its production is inhibited in people with type 2 diabetes, its function remains possible.
Type 2 diabetes tends to progress over time, so the treatment that’s right for you now, might change as your disease does, too. The good news is that there are a whole range of different options out there for each stage of the disease.
This article provides a topline overview to help people with type 2 diabetes begin discussions with their doctors. It is not a comprehensive document and not intended to replace the advice of a doctor or other healthcare professional.
If you’ve read some of our other blog posts, you’ll know that diet and exercise are powerful tools to help manage type 2 diabetes. However, in the long term most people will find that their diabetes evolves, so that they also need medication on top of diet and exercise to keep the many aspects of their disease under control.
Key organs involved in managing insulin and sugar levels that are potential targets for treatments
As discussed in this blog post, if you have type 2 diabetes, your body gradually stops making enough insulin and becomes less able to use the insulin it does make, effectively. The overall effect is that your blood sugar rises, becoming too high.
Diabetes medications try to bring your blood sugar under control by affecting how the body handles insulin and/or sugar.
All medicines can cause side effects in some people. If you do suffer from any, it’s worth talking to your doctor as there may be ways to manage the side effects, or there may be another medicine that could work better for you. Speak to your doctor to find out more.
People with type 2 diabetes should have their medications reassessed every 3–6 months. Are you on the right medication for you? Read on to find out more and be sure to discuss it with your doctor!
Biguanides (metformin)
Metformin is the first medicine that is generally prescribed to people with type 2 diabetes, who require medication in addition to diet and exercise to maintain their target blood sugar level. Metformin is the only medicine in the biguanide class and is taken orally as a tablet.
Metformin works by reducing the amount of sugar your liver releases into the blood and by helping your body respond better to insulin.
For those without cardiovascular disease, heart failure or chronic kidney disease
If you don’t need any extra protection for your heart or kidneys and your blood sugars are well-controlled, you may be able to stay on metformin alone. If your diabetes evolves and metformin is not enough to control you blood sugar alone, your doctor can recommend another treatment option.
There are a range of other treatment options available. The other main groups of medications are described below and with a range of different combinations being possible, the medication map will be there to support you to navigate the treatments landscape!
DPP-4is are oral medicines that help increase the amount of insulin produced after eating, and reduce the amount of sugar released by the liver when it’s not needed. They also slow down digestion.
These oral medicines increase the body’s sensitivity to insulin and can increase the amount of ‘good’ cholesterol in the blood too.
Sulfonylureas can be taken orally around a meal to simulate the production of insulin by the pancreas and increase the effectiveness of insulin in the body.
Although a diabetes doctor might prescribe one of these medicines to a range of different type 2 diabetes patients for a range of reasons, they may be particularly suited to people with cardiovascular disease, heart failure or chronic kidney disease and are discussed in the next section.
If you have read this blog post, you will know of the connection between type 2 diabetes and cardiovascular disease, which includes heart attacks and stroke (read more here). Preventing cardiovascular disease should therefore be a priority when considering with your doctor how to manage your type 2 diabetes. If you are at high risk of, or have already been diagnosed with cardiovascular disease, kidney disease and heart failure, a doctor might decide to add another medicine to metformin early on. This decision can be made even if metformin is working well to control your blood sugar levels.
Treatment with a medication from either the GLP-1 RA class or the SLGT2i class can reduce cardiovascular risk in suitable patients. For some people whose blood sugar levels remain high, it is possible to combine both classes of medication.
GLP-1 RAs can be given by a once-daily or once-weekly injection, under the skin or orally, depending on the medicine.
GLP-1 RA medicines work in a number of ways: they slow down food leaving your stomach and help reduce the amount of sugar released from your liver. When you blood sugar gets high, GLP-1 RAs also increase the amount of insulin released by your pancreas. Read more about GLP-1 treatment in this blog post.
SGLT2is are oral medicines. These medications work to reduce blood sugars by preventing the kidneys from reabsorbing sugar back into the blood and therefore increasing the amount of sugar lost in the urine.
If your blood sugars end up not being controlled on metformin and a GLP-1 RA, you may be prescribed an SGLT2i in addition, or vice versa. Alternatively, you can even be prescribed one of the other treatment options for type 2 diabetes.
As insulin is the hormone at the center of diabetes, it comes as no surprise that different insulins can also be used to treat type 2 diabetes. This blog post is all about the available insulin treatment options available and how they can be tailored to different people’s needs.
We hope that this blog post has given you an idea of just how many diabetes medicines are out there – when you consider the range of ways they can be combined, you can see there are a lot of possibilities! So, wherever you are with your diabetes, why not talk to your doctor to make sure that you are on the medication that can best support you at this time?
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