What is Metformin Used for Typically?

Primarily used to treat Type 2 diabetes, Metformin has shown positive results in treating Polycystic Ovary Syndrome (PCOS), which is a major cause of infertility. Available under different brand names, in different potencies, with immediate release and extended release (XR) options, this drug is administered differently to patients based on their individual needs.

According to the black box warning of this drug, side effects may include Lactic acidosis, which is a rare but severe condition caused by the accumulation of lactate in the body. Thus, restricting patients ‘ alcohol consumption when on Metformin is recommended. It should only be administered with food to avoid any bowel or stomach issues, especially at the beginning of the treatment.

Metformin Ingredients:

Metformin (belonging to the biguanides drug class), sometimes called a wonder drug, is the cornerstone of type 2 diabetes management in the U.S. The history of this medicine starts hundreds of years back; however, it was finally discovered in Europe in the 1950s and approved by the FDA in 1955. Its active ingredient, “hydrochloride”, simply refers to the salt form of metformin. This active ingredient decreases the amount of glucose production in the liver and increases the use of glucose in the body.

The inactive ingredients do not have any impact on your body however, they are added for a specific purpose. Examples include coating agents, which can control the drug’s release (e.g., in extended-release formulations). Binders help hold the tablet together.

Metformin Brands Names & Potencies:

In the USA, metformin is available under various brand names, some come which the extended release, including but not limited to Glucophage, Glucophage XR (extended release), Riomet, Glumetza (extended release), Fortamet (extended release), and more. The active ingredient in all these brands is metformin, a medication used to treat type 2 diabetes. The potencies (doses) of metformin range from 500 mg to 1000 mg, with extended-release versions offering different durations of action.

Brand Names and Potencies:

• Glucophage: Metformin hydrochloride, available in immediate-release (IR) tablets, 500 mg, 850 mg, and 1000 mg doses.
• Glucophage XR: Metformin hydrochloride extended-release (ER), available in 500 mg and 750 mg tablets.
• Glumetza: Metformin hydrochloride ER, available in 500 mg and 1000 mg tablets.
• Fortamet: Metformin hydrochloride ER, available in 500 mg (generic) and 1000 mg (brand name and generic) tablets.
• Riomet: Metformin hydrochloride solution, a liquid form of metformin.

Did you know?

You may be eligible to claim a CGM (continuous glucose monitor) sensor, e.g., Freestyle Libre 2 Plus or a Dexcom G7 (up to 10.5 days), using your insurance. A CGM system allows for a finger-prick-free and 24/7 blood sugar monitoring.

Key Considerations:

• Extended-Release (ER) Formulations:

ER versions like Glucophage XR, Glumetza, and Fortamet are designed to release the medication gradually over a longer period, potentially improving adherence and glycemic control.

• Dosing:

Metformin dosages are individualised by a healthcare provider and may need to be adjusted based on individual needs and response to treatment.

• Combination Products:

Metformin is also available in combination with other medications, such as DPP-4 inhibitors (Janumet, Kombiglyze) or SGLT2 inhibitors (Invokamet, Synjardy, Trijardy), to provide a more comprehensive approach to diabetes management.

What is Metformin Used For (Indications):

Metformin increases insulin sensitivity and decreases the production of glucose in the liver. Primarily used to treat type 2 diabetes, this drug has shown positive results in treating Polycystic Ovary Syndrome (PCOS), which is a major cause of infertility in women and a chronic hormonal disorder. PCOS is characterized by irregular periods, excess androgens, and polycystic ovaries. Although it cannot be cured but the symptoms could be managed with proper treatment.

1- Type 2 Diabetes:

• Metformin’s ability to suppress hepatic glucose production is vital. The liver in diabetic individuals often overproduces glucose, especially overnight. Metformin helps regulate this.
• Improving insulin sensitivity means that the body’s cells respond better to the insulin that is produced, allowing glucose to enter cells for energy.
• The reduction of intestinal glucose absorption is a secondary, but still significant, effect.

2- Polycystic Ovary Syndrome (PCOS):

• An endocrinological condition that causes insulin resistance, which leads to or exacerbates hormonal imbalances. Metformin can improve insulin sensitivity, potentially leading to more regular menstrual cycles and improved fertility in some women with PCOS.

Important: Do not break or crush an extended-release medicine, otherwise, it may not act the same way as it should.

How People May React to Metformin:

1- Common Side Effects:

• Gastrointestinal issues: These occur because metformin can affect gut motility and the absorption of nutrients. For example, diarrhoea can occur because metformin alters the way the intestines handle fluids.
• To minimise these effects, doctors often recommend starting with a low dose and gradually increasing it.

2- Less Common but Serious Side Effects:

• Lactic acidosis: This is a buildup of lactic acid in the bloodstream. It’s more likely to occur in individuals with kidney problems, as the kidneys play a vital role in clearing lactic acid. Symptoms can include muscle pain, fatigue, and difficulty breathing.

3- Individual Variability:

• Kidney function: Impaired kidney function can slow the clearance of metformin, increasing the risk of side effects. This is why kidney function is routinely checked before and during metformin treatment.
• Age: Older adults may be more susceptible to side effects due to age-related changes in kidney and liver function.

Drug Interactions:

1- Examples of Drug Interactions:

• Iodinated contrast media (used in some imaging procedures): These can temporarily impair kidney function, increasing the risk of lactic acidosis if taken with metformin. Therefore, metformin may be temporarily stopped before such procedures.
• Certain diuretics (water pills): Some diuretics can also affect kidney function, potentially increasing the risk of lactic acidosis.
• Drugs that affect blood sugar (e.g., corticosteroids): These can counteract the blood sugar-lowering effects of metformin, making it harder to control diabetes.
• Digoxin: Metformin can increase the levels of digoxin in the blood.
• Ranolazine: Ranolazine can increase the levels of metformin in the blood.

Pharmacogenomic (PGx) Testing:

Metformin is not metabolised mainly in the liver, instead, it works differently. This drug response is complex and influenced by many factors, including genetics, age, kidney function, other medications, and lifestyle. While genes are involved in the transport of the drug, a major portion of the medicine is carried out through renal excretion; thus, the kidney plays an important role. Hence, a PGx test can help but may not suffice as good as it caters in the case of mental health medications.

PGx reports can provide valuable information about how a person might respond to metformin, but they should not be used as the sole determinant of treatment decisions.

Book an at-home PGx testing kit now and see how you may respond to 250+ medications.

Table of Important Data:

Feature	Description	Important Notes
Primary Use	Type 2 diabetes management	Often first-line medication
Mechanism of Action	Decreases liver glucose production, improves insulin sensitivity, reduces intestinal glucose absorption	Works on multiple pathways
Common Side Effects	Gastrointestinal issues (nausea, diarrhoea)	Usually temporary
Serious Side Effects	Lactic acidosis	Rare but life-threatening
Drug Interactions	Iodinated contrast media, diuretics, corticosteroids	Requires careful monitoring
PGx Testing	Helps in dosage administration; however as there are several factors involved in how Metformin affects you, PGx is just part of the puzzle	Research ongoing

Conclusion:

Under various brand names in the US, Metformin belonging to biguanides is available in different potencies, with immediate-release (IR) and extended-release options (ER). This medicine lowers the production of glucose in the liver and increases insulin sensitivity, allowing the body to consume glucose better. Although rare, this drug could cause lactic acidosis, which is a severe condition. Doctors should restrict alcohol consumption in patients who are following this medication.

Disclaimer: This blog is only for informational purposes. Always consult a healthcare specialist before taking any medical action.

References:

https://www.ncbi.nlm.nih.gov/books/NBK409379/table/appa.t1/
https://www.alto.com/blog/post/difference-between-extended-and-immediate-release-medications