Medications are often prescribed to people with diabetes to help them lower their blood glucose levels (BGLs). It’s important to keep BGLs within the target range to reduce your risk of complications.

Most of the current medications focus mainly on insulin (the hormone that helps glucose to move from the blood into the muscles where it is used for energy). These diabetes medications work in different ways to help lower your BGLs by:

• stopping the liver from releasing too much stored glucose into the blood
• helping the muscle cells become more sensitive to the insulin your body makes
• helping the pancreas to make more insulin
  having insulin injections.

Recently, a new class of diabetes medication was released in Australia, known as sodium-glucose co-transporter (SGLT-2) inhibitors and two types of tablets are now available: Invokana (canagliflozin) and Forxiga (dapagliflozin). The SGLT-2 inhibitors work in a very different way, by targeting the kidneys.

Our kidneys filter our blood to remove waste from our body and to make sure important nutrients, such as glucose, are not removed from the body (since glucose is needed in the body for energy). Normally, all of the glucose that goes through the kidneys is reabsorbed, but if your BGLs are high (usually around 11mmols), this excess glucose is passed in the urine.

However, in type 2 diabetes where BGLs are higher than normal, your kidneys reabsorb more glucose. This means that the glucose in the blood stays high. The SGLT-2 inhibitors work by stopping the kidneys from reabsorbing this excess glucose.

What are the advantages of the new medications?

• Your kidneys reabsorb less glucose therefore your BGLs are lower. This will mean that your HbA1c is lower, and we know that having HbA1C seven per cent (53mmol/mol) or less can reduce your risk of developing diabetes complications.
• Losing excess glucose through your kidneys may lead to weight loss, as these are calories that are passed out. Losing weight can also help lower BGLs by helping the insulin you make work better.
• Taking these medications may also lead to a small drop in blood pressure, which is good for your heart and kidneys.

Are there any side effects?

Some of the side effects are:

• passing more urine because when excess glucose passes out of the kidneys more water is lost
• as extra fluid is lost, you may feel dizzy from a drop in blood pressure (so drinking enough fluid each day is important)
• because of the extra glucose in the urine, there is an increased risk of urine and genital infections, especially in women (these infections have been easily treated and most people can continue taking the medication)
• if your kidneys are not working well or if you are taking certain medications such as diuretics, the SGLT-2 inhibitors may not be recommended.

Often, when new medications are introduced it can be a few years before long-term side effects are seen. Research continues in this area.

Are these medications for everyone?

All medications have their advantages and disadvantages, and not all people respond the same way to medications. If you would like more information on this class of drugs or to find out if they are suitable for you, speak to your GP or endocrinologist.