Can metformin be taken with insulin?
022 Question I have diabetes for the past 4 years. Initially I was given Metformin and some other ta... Read more
022
Question
I have diabetes for the past 4 years. Initially I was given Metformin and some other tablets. I have checked my sugar levels recently. Although my fasting sugar level is always below 100mg/dl, it goes above 300mg/dl after having a meal. Now I am taking insulin and Metformin SR. Many people advised me that sugar tablets can dissolve the kidneys. I am worried about taking tablets. Can I take only insulin and stop Metformin?
Answer
Patients with diabetes should take treatment to control their blood glucose level. Poor glucose control can lead to various complications such as; heart attack, stroke, kidney failure, foot and nerve problems. For some diabetic patients, lifestyle changes alone would be enough to control their glucose level in the initial stage whereas many would require medications as well.
Insulin is an important hormone in controlling blood glucose. It is naturally produced in our body by the pancreas. The pancreas is a flat, half-foot long organ located beneath and behind the stomach. If the body does not produce enough insulin, or if the insulin becomes less effective (i.e. insulin resistance), diabetes ensues. Metformin helps the body to better utilise even lower amounts of insulin.
When a person is diagnosed with diabetes, the doctor determines the treatment plan considering the presenting symptoms, blood test results and the type of diabetes. There are two main types of diabetes; type 1 and type 2. There are other minor types of diabetes which are not common. In type 1 diabetes there is no natural production of insulin in the body and such patients should be given insulin from outside. Most patients with type 2 diabetes do not require insulin in the beginning. As their disease progresses, their glucose level may not be controlled with diet, exercise and oral medications. In this situation, they too would require insulin treatment.
Metformin is in use for diabetes for a long period of time. It controls the blood glucose in multiple ways. Metformin SR means slow releasing form of metformin. This formula has less side effects and is better tolerated by many patients.
Further details about metformin can be found in this article: How does metformin work?
When treating patients with diabetes the doctors aim to keep both the Fasting Blood Sugar (FBS) and Post Prandial Blood Sugar (PPBS – blood glucose level after meals) under control. This control is very important to minimise the long-term complications which can occur due to elevated glucose levels. In the initial stage of diabetes, the PPBS will usually be high even if the FBS is normal.
There are several types or analogues of insulin. Their onset and duration of action differ. Long-acting form of insulin controls FBS whereas short-acting form control PPBS. Some formulas of insulin contain both short-acting and long-acting types mixed at certain proportion. They can control both FBS and PPBS.
It is a common myth that Metformin causes kidney failure. But the fact is as follows. Metformin protects the kidneys by keeping the blood glucose under control. On the contrary, elevated blood glucose level damages the kidneys, eyes, heart, brain and nerves.
The detailed description of metformin’s role in protecting kidneys can be found in this article: Metformin and kidney failure
Many patients with type 2 diabetes ultimately end up using insulin. Diabetes is a progressive disease and with time the level of naturally produced insulin declines in the body. When insulin production reaches critically low level, it should be given from outside. In the late stages of type 2 diabetes there are added benefits of taking metformin along with insulin. Because metformin can increase the effectiveness of the insulin. This questioner seems to be having type 2 diabetes which progressed over time requiring insulin as well. Therefore, it is advisable to continue both medications. However, it is important to follow the advice of the treating doctor and optimise the dose of medications to keep the glucose level under control.
Author: Nawras
References
- American Diabetes Association. 2020. “Diabetes Care.” January 1. https://care.diabetesjournals.org/content/43/Supplement_1.
- CJ, Bailey. 2017. “Metformin: historical overview.” Diabetologia 60 (9): 1566-1576. doi:10.1007/s00125-017-4318-z.
- International Diabetes Federation. 2020. Type 2 diabetes. March 20. Accessed September 13, 2020. https://idf.org/aboutdiabetes/type-2-diabetes.html.
- NICE Guideline. 2019. Type 2 diabetes in adults: management. August 28. Accessed September 13, 2020. https://www.nice.org.uk/guidance/ng28.
