Metformin drug interactions

Drug interactions can precipitate metformin-induced lactic acidosis, as has been reported after the addition of indometacin (144). 

TOPIRAMATE ANTIDIABETIC DRUGS-METFORMIN T metformin levels Unknown mechanism Watch for and warn patients about hypoglycaemia - For signs and symptoms of hypoglycaemia, see Clinical Features of Some Adverse Drug Interactions, Hypoglycaemia... 

METFORMIN H2 RECEPTOR BLOCKERS -CIMETIDINE, RANITIDINE t level of metformin and risk of lactic acidosis. The onset of lactic acidosis is often subtle with symptoms of malaise, myalgia, respiratory distress and t nonspecific abdominal distress. There may be hypothermia and resistant bradyarrhythmias Metformin is not metabolized in humans and is not protein-bound. Competition for renal tubular excretion is the basis for T activity or retention of metformin. Cimetidine competes for the excretory pathway A theoretical possibility. Need to consider l dose of metformin or avoidance of co-administration. Warn patients about hypoglycaemia - For signs and symptoms of hypoglycaemia, see Clinical Features of Some Adverse Drug Interactions, Hypoglycaemia... 

Examples of some drugs whose activity is increased in liver disease include oral anticoagulants, metformin, chloramphenicol, NSAIDs and sulphonylureas. It is well known that drugs such as opioids should be used in reduced dosage in patients with hepatic dysfunction doses need to be titrated, Therefore, if adverse drug interactions with opioids occur in patients with liver dysfunction, the consequences such as respiratory depression could be life-threatening,... 

Jayasagar G, Krishna Kumar M, Chandrasekhar K, Madhusudan Rao C, Madhusudan Rao Y. Effect of cephalexin on the pharmacokinetics of metformin in healthy human volunteers. Drug Metabol Drug Interact 2002 19(l) 41-8. 

Metformin achieves a 23% lower mean HbAi than placebo (Dornan etal., 1991). Unlike sulphonylureas, it is not bound to plasma proteins (no drug interactions), is not metabolized and is eliminated rapidly by the kidney (Bailey, 1992). 

Drug Interactions. Cimetidine competes for renal tubular secretion of metformin and concomitant administration leads to higher metformin serum concentrations. At least one case report of lactic acidosis with metformin therapy implicates cimetidine. Other cationic... 

Drug interactions metabolized by CYP450 3A4, may interact with drugs that inhibit or induce this enzyme May cause hypoglycemia in patients receiving insulin, sulfonylureas, or metformin contraindicated in pregnant women Limit vitamin A supplements... 

---