Essential Blood Tests for Patients on SGLT2 Inhibitors

SGLT2 inhibitors are a class of medications used to manage type 2 diabetes by helping the kidneys remove glucose from the body through urine. While these drugs can be effective in controlling blood sugar levels, they can also affect other aspects of health that need to be monitored through blood tests.

Why Monitoring is Important

When taking SGLT2 inhibitors, it's crucial to keep an eye on certain blood markers to ensure the medication is working effectively and safely. Monitoring helps detect any potential side effects early, allowing for timely intervention. Two key areas of concern are kidney function and the risk of ketoacidosis, a serious condition that can occur even if blood sugar levels are not extremely high.

Kidney Function Tests

SGLT2 inhibitors can impact kidney function, so it's important to monitor kidney health regularly. Two primary tests are used:

• Serum Creatinine: This test measures the level of creatinine in your blood, a waste product filtered by the kidneys. An increase in serum creatinine is expected when starting SGLT2 inhibitors and does not necessarily indicate new kidney damage.
• Estimated Glomerular Filtration Rate (eGFR): This test estimates how well your kidneys are filtering blood. Before starting SGLT2 inhibitors, and periodically thereafter, your eGFR should be checked, especially if it is below 60 mL/min/1.73 m².

Monitoring for Ketoacidosis

Ketoacidosis is a potentially life-threatening condition where the body produces excessive ketones, leading to an acidic state in the blood. It can occur even if blood glucose levels are not extremely high, a situation known as euglycaemic ketoacidosis. Symptoms include nausea, vomiting, abdominal pain, and confusion. It's crucial to assess for ketoacidosis if these symptoms arise, regardless of blood glucose levels.

Alternative Glycaemic Monitoring

Traditional urine glucose tests are not recommended for patients on SGLT2 inhibitors because these drugs increase the amount of glucose excreted in urine, leading to false positives. Instead, alternative methods such as blood glucose tests should be used to monitor glycaemic control.

Frequently asked questions

Can I rely on urine glucose tests to monitor my diabetes if I'm taking SGLT2 inhibitors? No, urine glucose tests are not reliable for patients on SGLT2 inhibitors as these medications increase urinary glucose excretion, leading to positive results regardless of blood sugar control.

What should I do if my serum creatinine levels increase after starting SGLT2 inhibitors? An increase in serum creatinine is an expected effect of SGLT2 inhibitors and does not necessarily indicate kidney damage. However, it's important to discuss any changes with your healthcare provider.

What are the signs of ketoacidosis I should watch for? Signs of ketoacidosis include nausea, vomiting, abdominal pain, and confusion. Seek urgent medical care straight away if you experience these symptoms, even if your blood sugar levels are not high.

When to see a doctor

If you have symptoms of ketoacidosis such as repeated vomiting, abdominal pain, deep or fast breathing, drowsiness or confusion, seek urgent medical care straight away, even if your blood sugar is not high. See your doctor if you have concerns about kidney function. Regular check-ups are essential to ensure your treatment is effective and safe.

Always consult with your healthcare provider to interpret your test results and make informed decisions about your health.