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Metformin / repaglinide Side Effects

Medically reviewed by Last updated on May 31, 2022.


Commonly reported side effects of metformin/repaglinide include: lactic acidosis, diarrhea, hypoglycemia, and nausea. Other side effects include: decreased vitamin b12 serum concentrate. Continue reading for a comprehensive list of adverse effects.

Applies to metformin/repaglinide: oral tablet.


Oral route (Tablet)

Post-marketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The onset of metformin-associated lactic acidosis is often subtle, accompanied only by nonspecific symptoms such as malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Metformin-associated lactic acidosis was characterized by elevated blood lactate levels (greater than 5 mmol/L), anion gap acidosis (without evidence of ketonuria or ketonemia), an increased lactate/pyruvate ratio; and metformin plasma levels generally greater than 5 mcg/mL. Risk factors include renal impairment, concomitant use of certain drugs (eg, carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (eg, acute congestive heart failure), excessive alcohol intake, and hepatic impairment. If suspected, immediately discontinue repaglinide/metformin and institute general supportive measures in a hospital setting. Prompt hemodialysis is recommended.

Serious side effects

Along with its needed effects, metformin / repaglinide may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking metformin / repaglinide:

More common

Other side effects

Some side effects of metformin / repaglinide may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

For Healthcare Professionals

Applies to metformin / repaglinide: oral tablet.



Very common (10% or more): Gastrointestinal system disorder (33%), diarrhea (19%), nausea (15%)


Very common (10% or more): Gastrointestinal system disorder (36%)

Common (1% to 10%): Diarrhea, nausea

Postmarketing reports: Pancreatitis


Very common (10% or more): Gastrointestinal system disorder (48%), diarrhea (30%)

Common (1% to 10%): Nausea[Ref]



Postmarketing reports: Severe hepatic dysfunction including jaundice and hepatitis[Ref]

Nervous system

Frequency not reported: Headache[Ref]



Very common (10% or more): Upper respiratory tract infection (11%)


Very common (10% or more): Upper respiratory tract infection (11%)


Common (1% to 10%): Upper respiratory tract infection (11%)[Ref]



Postmarketing reports: Hemolytic anemia[Ref]



Postmarketing reports: Stevens-Johnson syndrome, alopecia[Ref]


Cardiovascular events were evaluated in trials comparing repaglinide to sulfonylureas. Serious cardiovascular events including ischemia with this drug were higher at 4% (51/1228) than for sulfonylurea drugs (3%; 13/498). No excess mortality was associated with this increase. Selected cardiovascular events including hypertension, abnormal EKG, MI, arrhythmias, and palpitations were observed at 1% or less and no more frequently with this drug than with comparator drugs.

Across 7 repaglinide clinical trials, 6 serious events of myocardial ischemia occurred in combination use with NPH-insulin compared with 1 event in patients using insulin alone. Repaglinide should not be used in combination with NPH insulin.


Common (1% to 10%): myocardial ischemia, angina, chest pain

Frequency not reported: Hypertension, abnormal EKG, MI, arrhythmias, palpitations


The most frequently reported adverse reactions included hypoglycemia and headache.



Very common (10% or more): Symptomatic hypoglycemia (33%)


Very common (10% or more): Symptomatic hypoglycemia (11%)


Common (1% to 10%): Subnormal vitamin B12 levels

Rare (less than 0.1%): Lactic acidosis

More about metformin / repaglinide

Patient resources

Other brands


Professional resources

Related treatment guides


1. "Product Information. PrandiMet (metformin-repaglinide)." Novo Nordisk Pharmaceuticals Inc (2008):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.