Initiation of your diabetes medication therapy is always based on your fasting blood-glucose level FinflBG), postprandial blood-glucose level (PPG) and A1C percentage.
The impact of FPG to A1C is dominating in patients with poorly managed blood glucose. The influence of FPG is about 70% in patients whose A1C is nearby 10.2%. As the blood-glucose level improves, PPG contribution dominates to about 70% when the A1C values close by 7.3%. Postprandial hyperglycemia is the earliest abnormalities of glucose homeostasis associated. And fasting hyperglycemia exaggerates it.
In one study, PPG monitoring has been shown to improve outcomes in gestational diabetes. However, it appears that FPG is somewhat better than PPG in predicting HbA1c, especially in diabetes type 2.
Two significant groups of diabetes drugs
There are two significant groups of oral hypoglycemic medications; they are sulphonylureas (SUs) and biguanides (BGs). SU act by stimulating insulin release from the beta cells and by promoting its action through other pancreatic mechanisms. BG exerts their effect by decreasing gluconeogenesis and by increasing the peripheral utilization of glucose.
If possible, choose sulfonylureas as an initial therapy in non-obese patients since they are cheaper as compared to the newer agents. Choose metformin as an initial agent for obese patients (i.e., those more than 120 % of their ideal body weight) or as an add-on therapy in patients who is not able to control with a sulfonylurea. The alpha-glucosidase inhibitor may be an alternative to sulfonylurea or as add-on therapy to metformin in patients with uncontrolled blood glucose or significant renal dysfunction.
Over the past decade, a significant interest in postprandial glucose (PPG) has emerged, because of new medications explicitly targeting PPG. These include insulin analogs (lispro and aspart), insulin secretagogues (repaglinide and nateglinide), alpha-glucosidase inhibitors (miglitol and acarbose), and injectable amylin analogs and glucagon-like peptide receptor agonists.
Appropriate targeting of plasma glucose may help to reduce expenses and limit unnecessary testing and may help achieve glucose goals faster. Targeting fasting plasma glucose is more beneficial when A1C results are very high. Whereas targeting postprandial glucose is more effective when A1C results are lower.
Oral Hyperglycemic Agents glucose-lowering strength | |||
Agent | Avg. FBG reduction (%) | Avg. PPG reduction (%) | Avg. A1C lowering (%) |
Sulfonylureas | 25 to 40 | 20 | 2.0 |
α-glucosidase inhibitors | 10 to 20 | 40 to 45 | 0.5 to 1.5 |
Metformin | 20 to 40 | 25 | 1.5 to 2.0 |
Steps in choosing correct diabetes medication
- During diagnosis, if your A1C level is less than 7% or fasting blood glucose less than 130mg/dl or 7.223 mmol/l, you can manage your diabetes with lifestyle changes (diet and exercise).
- If your A1C level is 7% or fasting blood glucose level of 130mg/dl or 7.223 mmol/l, you should start your diabetes treatment with a monotherapy (single medication). Preferably, Biguanides (Metformin) or Sulphonylureas is considering as a first-line diabetes mono-therapy.
- If the monotherapy failed to produce the result, means your FBG stays at more than 130 mg/dl or 7.223 mmol/l after six weeks of treatment or A1C more than 7% after 12 weeks. Now, you may consider dual-therapy with the combination of two different classes of diabetes drug. Preferable choices are Metformin + Sulphonylurea, alternatively Sulphonylurea + Thiazolidinediones.
- If the dual-therapy failed to produce the result; i.e. your FBG stays at more than 130 mg/dl or 7.223 mmol/l after six weeks of treatment or A1C more than 7% after 12 weeks. Now, you may consider triple-therapy with the combination of three different classes of diabetes drug. Preferable choices are Metformin + Sulphonylurea + Thiazolidinediones, alternatively Metformin + Thiazolidinediones + DPP4 or Metformin + Sulphonylurea + GLP1 or Metformin + Thiazolidinediones + GLP1 or Metformin + Sulphonylurea + basal insulin.
- During diagnosis, if your A1C level is more than 9%, start dual-therapy with the combination of two different classes of diabetes drug. Preferable choices are Metformin + Sulphonylurea, alternatively Sulphonylurea + Thiazolidinediones.
- If the dual-therapy failed to produce the result; i.e., your FBG stays more than 130 mg/dl or 7.223 mmol/l after six weeks of treatment or A1C more than 7% after 12 weeks. Now you may consider triple-therapy with the combination of three different classes of diabetes drug. Preferable choices are Metformin + Sulphonylurea + Thiazolidinediones, alternatively Metformin + Thiazolidinediones + DPP4 or Metformin + Sulphonylurea + GLP1 or Metformin + Thiazolidinediones + GLP1 or Metformin + Sulphonylurea + basal insulin.
- During diagnosis, if your A1C level is more than 10 with severe symptoms, start metformin, and insulin therapy. Reach your target value by increasing the dosage of both medications. Continue oral medication; additionally, take intermediate or long-acting insulin before bedtime with an initial dose of 0.2 U/kg or 0.9 U/Lb. Monitor FPG and accordingly adjust insulin by 2 to 4 units after at least three days. FPG target should be 72 mg/dl to 144 mg/dl (or 4 to 8 mmol/L) based on your health condition.
Never exchange your diabetes medicines with others
Each diabetes medication has a different mechanism of action. Your doctor prescribes your drug based on a complete understanding of your condition. Henceforth, exchange doctors if you must but never exchange your drugs.