Metformin (Glucophage) Flashcards

Study Notes

Metformin (Glucophage) Overview

Therapeutic class: antidiabetic
Pharmacologic class: biguanides

Indications and Mechanism of Action

Used for managing Type 2 diabetes.
Mechanism of action includes:
- Decreasing hepatic glucose production.
- Reducing intestinal glucose absorption.
- Increasing insulin sensitivity.
Therapeutic effects: maintains blood glucose levels.

Side Effects

Major side effects include:
- Gastrointestinal: abdominal bloating, diarrhea, nausea, vomiting, and an unpleasant metallic taste.
- Electrolyte imbalance risk: lactic acidosis.
- Miscellaneous: may decrease vitamin B12 levels.

Adult Dosage Parameters

Oral dosage for adults and children over 17 years:
- Start with 500 mg twice daily, may increase by 500 mg weekly up to 2000 mg/day.
- For doses over 2000 mg/day, administer in 3 divided doses (max 2500 mg/day) or 850 mg once daily, increasing as needed.
- Extended-release: 500-1000 mg once daily with evening meal, can increase by 500 mg weekly to a maximum of 2500 mg once daily.

Nursing Interventions

Assess patients with illness for signs of ketoacidosis or lactic acidosis:
- Check serum electrolytes, ketones, glucose, and relevant blood levels.
- Discontinue metformin if acidosis is present.
Monitor renal function before starting and annually during treatment; discontinue if renal impairment occurs.
Watch serum folic acid and vitamin B12 levels every 1-2 years due to absorption interference.
Patients under stress (fever, trauma, infection, surgery) may need insulin; suspend metformin temporarily.
Educate patients on lactic acidosis risks and the need for discontinuation during severe conditions.
Review signs of hypoglycemia and hyperglycemia with patients; provide guidance on managing hypoglycemic episodes.
Instruct patients on blood glucose and urine ketone testing, especially during illness or stress.

Important Notes and Considerations

Symptoms of lactic acidosis must be reported immediately; include chills, diarrhea, dizziness, low blood pressure, muscle pain, sleepiness, slow heartbeat, dyspnea, or weakness.
Assess renal function and monitor liver function tests (LFTs), creatinine, serum folic acid, and B12 levels regularly.
In cases where metformin is combined with iodine contrast, hold the medication on the imaging day and for 48 hours afterwards to prevent kidney damage.
Extended-release tablets should be swallowed whole without chewing.

Description

Test your knowledge on Metformin (Glucophage) with these flashcards. Covering its therapeutic and pharmacologic classes, indications, mechanisms of action, and therapeutic effects, this quiz provides a comprehensive review for anyone studying diabetes management.