What class is the drug ? Biguanide Drug - Biguanide - Ethymology - Bi- Guanide- Guanide was first isolated from Peruvian guano and takes its name from this.
What does it do? - What is the Pharmacological Mecchanism - Suppresses Hepatic Gluconeogenesis - Also increases insulin sensitivity, enhances peripheral glucose uptake (by inducing the phosphorylation of GLUT4 enhancer factor), decreases insulin-induced suppression of fatty acid oxidation, and decreases absorption of glucose from the gastrointestinal tract.
Oral Bioavailability 50-60% when fasting - tmax 2.5h Halflife - 6.5 h. Renal Elimination - Not metabolized by the body, excreted unchanged. With prolongued release tmax 7 hours
History - Used from Goat's Rue - liliac flower for centuries as a medicinal herb. Started being used as Active compound in france in 1950s.
Is it safe and in which cases is it not safe - Safety 9/10
CKD or Dehydration
Hepatic Impairment or Alcoholism
Is there a proven benefit? Yes
Diabetics taking metformin had significantly lower all-cause mortality than non-diabetics (hazard ratio (HR)=0.93, 95%CI 0.88-0.99), as did diabetics taking metformin compared to diabetics receiving non-metformin therapies (HR=0.72, 95%CI 0.65-0.80), insulin (HR=0.68, 95%CI 0.63-0.75) or sulphonylurea (HR=0.80, 95%CI 0.66-0.97). Metformin users also had reduced cancer compared to non-diabetics (rate ratio=0.94, 95%CI 0.92-0.97) and cardiovascular disease (CVD) compared to diabetics receiving non-metformin therapies (HR=0.76, 95%CI 0.66-0.87) or insulin (HR=0.78, 95%CI 0.73-0.83).
(Metformin reduces all-cause mortality and diseases of ageing independent of its effect on diabetes control: A systematic review and meta-analysis.)
- Erectile Dysfunction
We report that metformin treatment positively affects two of three pathways, specifically through enhanced endothelium-dependent vasodilation and sympathetic nerve activity attenuation ( Paper - Effects of metformin on endothelial health and erectile dysfunction )
Hep B infections co-adjuvant action along with Current Anti-virals
Metformin Treatment Cons -
- Kidney Disease - Mecchanism - fosters Lactic Acid Production