Which group of patients is NOT at increased risk of adverse effects from Metformin?

The group that is not at increased risk of adverse effects from Metformin is obese patients. Metformin is primarily used as a therapeutic agent for managing type 2 diabetes, particularly in individuals who are overweight or obese. Its efficacy is often enhanced in this population, as they tend to benefit from the drug's ability to improve insulin sensitivity and help with weight management.

In contrast, patients with renal disease are at risk because Metformin is primarily excreted by the kidneys; impaired renal function can lead to drug accumulation and increase the chance of lactic acidosis. Similarly, patients with hypoxia may experience increased risk since conditions that decrease oxygen delivery to tissues can potentiate lactic acidosis, a serious side effect of Metformin. Alcoholics also face elevated risks, as alcohol consumption can further impair liver function and contribute to lactic acidosis, particularly when combined with Metformin use.

Thus, while certain patient groups present significant risks when prescribed Metformin, obese patients do not share these elevated risks, and instead, they typically experience favorable effects from its use.