From the Guidelines
Patient education for individuals starting metformin therapy should focus on proper administration, side effects, and monitoring requirements, as recommended by the 2017 American Diabetes Association standards of medical care in diabetes 1.
Key Points for Patient Education
- Patients should take metformin with meals to minimize gastrointestinal side effects, which commonly include nausea, diarrhea, abdominal discomfort, and metallic taste.
- A gradual dose titration is recommended, often starting with 500 mg once daily with dinner, then increasing to twice daily, and eventually reaching the target dose of 1000-2000 mg daily divided into two doses.
- Patients should be informed about the risk of lactic acidosis, a rare but serious side effect, and taught to recognize symptoms like unusual muscle pain, difficulty breathing, unusual sleepiness, and stomach discomfort.
- They should understand the importance of temporarily stopping metformin during acute illness, before receiving IV contrast for imaging studies, or before surgical procedures.
- Patients need regular monitoring of kidney function, as metformin is contraindicated in severe kidney disease.
- They should also be aware that metformin may reduce vitamin B12 levels over time, potentially requiring supplementation, as noted in the Diabetes Prevention Program Outcomes Study 1.
- Alcohol should be limited while taking metformin due to increased risk of lactic acidosis.
- Patients should continue lifestyle modifications including diet and exercise alongside medication therapy for optimal diabetes management, as emphasized by the American Diabetes Association and the European Association for the Study of Diabetes position statement 1.
Monitoring and Follow-Up
- Regular monitoring of kidney function is essential, as metformin is contraindicated in severe kidney disease.
- Periodic testing of vitamin B12 levels should be considered in metformin users, especially those with anemia or peripheral neuropathy 1.
- Patients should be advised to stop taking their medication if they experience nausea, vomiting, or dehydration, and to seek medical attention if they experience symptoms of lactic acidosis.
From the FDA Drug Label
17 PATIENT COUNSELING INFORMATION
Advise the patient to read the FDA-approved patient labeling (Patient Information). Lactic Acidosis: Explain the risks of lactic acidosis, its symptoms, and conditions that predispose to its development Advise patients to discontinue metformin hydrochloride tablets immediately and to promptly notify their healthcare provider if unexplained hyperventilation, myalgias, malaise, unusual somnolence or other nonspecific symptoms occur Counsel patients against excessive alcohol intake and inform patients about importance of regular testing of renal function while receiving metformin hydrochloride tablets. Instruct patients to inform their doctor that they are taking metformin hydrochloride tablets prior to any surgical or radiological procedure, as temporary discontinuation may be required
The recommended patient education for individuals starting metformin therapy includes:
- Lactic Acidosis: explaining the risks, symptoms, and predisposing conditions
- Symptom monitoring: advising patients to discontinue metformin and notify their healthcare provider if they experience unexplained symptoms such as hyperventilation, myalgias, malaise, or unusual somnolence
- Alcohol intake: counseling against excessive alcohol consumption
- Renal function testing: informing patients about the importance of regular renal function testing
- Surgical or radiological procedures: instructing patients to inform their doctor about metformin use prior to any procedure, as temporary discontinuation may be required 2
From the Research
Patient Education for Metformin Therapy
Patient education is crucial for individuals starting metformin (biguanide) therapy to ensure safe and effective use of the medication. The following points should be considered:
- Administration and Dosing: Metformin should be taken with meals to minimize gastrointestinal side effects, and the dose should be gradually titrated upward to reduce the risk of adverse effects 3.
- Common Side Effects: Patients should be aware of the common side effects of metformin, including mild, transient gastrointestinal symptoms such as diarrhea, nausea, and vomiting, which are usually self-limiting 3, 4.
- Lactic Acidosis: Although rare, patients should be informed about the risk of lactic acidosis associated with metformin use, particularly in those with contraindications such as renal or hepatic impairment 3, 5.
- Extended-Release Formulation: Patients who experience gastrointestinal intolerance with immediate-release metformin may benefit from switching to an extended-release formulation, which can improve tolerability and allow for once-daily dosing 4, 6.
- Monitoring and Follow-up: Regular monitoring of blood glucose levels, renal function, and liver function is essential to ensure safe use of metformin and to adjust the dose as needed 7, 5.
- Contraindications and Precautions: Patients should be aware of the contraindications and precautions associated with metformin use, including renal or hepatic impairment, and should inform their healthcare provider about any underlying medical conditions or medications that may interact with metformin 3, 5.
Key Takeaway Points
- Metformin is a well-established medication for the treatment of type 2 diabetes mellitus.
- Patient education is crucial to ensure safe and effective use of metformin.
- Common side effects of metformin include gastrointestinal symptoms, which can be minimized by taking the medication with meals and gradually titrating the dose.
- Lactic acidosis is a rare but serious complication associated with metformin use, and patients should be informed about the risks and symptoms.
- Extended-release metformin can improve tolerability and allow for once-daily dosing in patients who experience gastrointestinal intolerance with immediate-release metformin.