Acarbose Vs. Metformin: Drug Comparison

Acarbose is an oral medication used to manage type 2 diabetes by slowing the breakdown of carbohydrates into glucose, which helps reduce blood sugar spikes after meals. It works by inhibiting enzymes in the small intestine that digest carbohydrates. Its FDA-approved indication is for the treatment of type 2 diabetes, often used alongside diet and exercise or other diabetes medications. Off-label uses may include management of reactive low blood sugar or use in polycystic ovary syndrome (PCOS) for insulin resistance, although these are less common. Acarbose is available in tablet form, with common side effects including gastrointestinal issues like abdominal pain, bloating, diarrhea, and flatulence, while drug interactions can occur with other diabetes medications, potentially increasing the risk of low blood sugar. Acarbose should be used cautiously in people with gastrointestinal conditions.

Metformin is an oral medication commonly prescribed to manage blood sugar levels in individuals with type 2 diabetes. It works by decreasing glucose production in the liver, improving the body's sensitivity to insulin, and reducing the amount of sugar absorbed by the intestines. Metformin is often used as a first-line treatment due to its efficacy, safety profile, and additional benefits, such as weight stabilization and low risk of low blood sugar. Common side effects include gastrointestinal issues like nausea, diarrhea, and abdominal discomfort.

Alpha-glucosidase inhibitor

Biguinide

Acarbose is indicated:

• As an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus

Metformin hydrochloride tablets are indicated:

• As an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients 10 years of age and older with type 2 diabetes mellitus

• Typically taken orally three times daily

• Comes in 25 mg, 50 mg, and 10 mg tablets

• Typically taken orally once, twice, or three times daily

• Comes in 500 mg, 850 mg, and 1,000 mg tablets

The most common symptoms are gastrointestinal and include:

• Abdominal pain

• Diarrhea

• Flatulence

For metformin hydrochloride, the most common adverse reactions (>5%) are:

• Diarrhea

• Nausea/vomiting

• Flatulence

• Weakness

• Indigestion

• Abdominal discomfort

• Headache

• Inflammatory bowel disease, colonic ulceration, partial intestinal obstruction, or in patients predisposed to intestinal obstruction

• Chronic intestinal diseases associated with marked disorders of digestion or absorption and conditions that may deteriorate as a result of increased gas formation in the intestine

• Drug interactions: drugs that tend to produce high blood sugar, sulfonylureas, insulin, intestinal absorbents, digoxin

• Severe renal impairment (eGFR below 30 mL/min/1.73 m²)

• Hypersensitivity to metformin

• Acute or chronic metabolic acidosis, including diabetic ketoacidosis, with or without coma

• Drug interactions: Carbonic anhydrase inhibitors, drugs that reduce metformin clearance (such as ranolazine, vandetanib, dolutegravir, and cimetidine), alcohol

• There have been no clinical studies establishing conclusive evidence of macrovascular risk reduction with acarbose

• Low blood sugar

• Elevated serum transaminase levels

• Loss of control of blood sugar

• Pregnancy: The safety of acarbose in pregnant women has not been established

• Breastfeeding: Acarbose should not be administered to a nursing woman

• Lactic acidosis: See Boxed Warning

• Vitamin B12 deficiency: Metformin may lower vitamin B12 levels

• Low blood sugar with concomitant use with insulin and insulin secretagogues

• Females and males of reproductive potential: Potential for an unintended pregnancy

WARNING: LACTIC ACIDOSIS

Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. Symptoms included malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Laboratory abnormalities included elevated blood lactate levels, anion gap acidosis, increased lactate/pyruvate ratio; and metformin plasma levels generally >5 mcg/mL.

Risk factors include renal impairment, concomitant use of certain drugs, age >65 years old, radiological studies with contrast, surgery and other procedures, hypoxic states, excessive alcohol intake, and hepatic impairment. Steps to reduce the risk of and manage metformin-associated lactic acidosis in these high risk groups are provided in the Full Prescribing Information.

If lactic acidosis is suspected, discontinue metformin hydrochloride tablets and institute general supportive measures in a hospital setting. Prompt hemodialysis is recommended.

*This information is from the acarbose label used by Chartwell RX, LLC. See the Full Prescribing Information for more complete information. Acarbose may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient acarbose.

*This information is from the metformin hydrochloride label used by Epic Pharma, LLC. See the Full Prescribing Information for more complete information. Metformin may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient metformin.