Diabetes: monitoring and treating
Targets for blood sugar control
Your target blood sugar level depends on many factors, including whether you have type 1 or type 2 diabetes mellitus, your age, overall health, social support system and personal preferences.
It's important that people with diabetes stabilise their blood glucose levels. What is termed 'acceptable' blood glucose levels can vary slightly but, as a general rule of thumb, fasting blood glucose levels should be less than 6.0 mmol/L, while non-fasting levels should be 4-8 mmol/L.
It has been shown that keeping your blood glucose as close as possible to normal reduces the risk of long-term complications of diabetes.
People with type 1 diabetes require insulin replacement therapy. Insulin preparations may be:
- Very-short-acting, such as insulin aspart (NovoRapid), insulin glulisine (Apidra) and insulin lispro (Humalog).
- Short-acting, such as neutral insulin (e.g. Actrapid).
- Intermediate-acting, such as isophane insulin (e.g. Humulin NPH).
- Long-acting, such as insulin detemir (Levemir) and insulin glargine (Lantus).
A combination of these is often given several times each day. In the past few years, different types of insulins have been combined into one convenient delivery device. For example, some of the pen-style delivery devices combine short-acting and intermediate-acting insulin (biphasic or 'pre-mixed' insulins) to reduce the number of injections required and to avoid the need to mix 2 insulins together from separate vials before injecting.
Many people with type 2 diabetes can be managed through diet and exercise alone. However, others require the addition of an oral hypoglycaemic (blood sugar lowering) agent. There are several types of oral hypoglycaemic agents, and some of these can be combined for added effect. Oral hypoglycaemics include:
- Biguanides, such as metformin (e.g. Diabex).
- Sulfonylureas, such as glibenclamide (Daonil, Glimel), gliclazide (e.g. Diamicron), glimepiride (e.g. Amaryl), and glipizide (e.g. Minidiab).
- Alpha-glucosidase inhibitors, such as acarbose (Glucobay).
- Thiazolidinediones (also known as glitazones), such as pioglitazone (e.g. Actos) and rosiglitazone (Avandia).
- Glitinides, such as repaglinide (NovoNorm).
- Dipeptidyl peptidase-4 (DPP-4) inhibitors (also known as incretin enhancers), such as saxagliptin (Onglyza), sitagliptin (Januvia) and vildagliptin (Galvus).
There is another hypoglycaemic agent that works in a similar way to the DPP-4 inhibitors but must be injected rather than taken orally - exenatide (Byetta).
When hypoglycaemic therapy fails to control blood sugar levels, insulin injections are required.
Monitoring blood glucose levels
Glucose monitoring kits that include a small meter and lancet device are widely available.
Most people with type 1 diabetes, and usually anyone taking oral hypoglycaemic medicines, are advised to monitor their blood sugar levels frequently. Blood glucose monitoring in type 2 diabetes controlled by diet and exercise is useful to find out if treatment goals are being met.
Blood glucose monitors usually provide a digital reading of your blood glucose level and different models are available to suit people who have poor eyesight or other disabilities. Many blood glucose monitors store the readings in their memory; this data can be downloaded onto a computer and analysed to aid your doctor in making treatment decisions about your diabetes.
Calibration and servicing of blood glucose meters are required to ensure that the devices remain accurate. Manufacturers of these devices frequently offer a high level of support for users.
People who are unable to perform blood glucose testing may be advised to test their urine for glucose, using urine test strips, although these results may not be acurate.
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