02/04/2026
Blood Work You Should Check Before Starting a GLP-1
GLP-1 medications influence insulin signaling, appetite regulation, gastric emptying, and overall metabolic demand. Because of these systemic effects, baseline blood work is essential before starting therapy. Labs provide objective insight into glucose control, insulin resistance, liver and kidney function, thyroid status, inflammation, and nutrient stores. Without this data, important contributors to weight gain, fatigue, or metabolic dysfunction may go unrecognized.
Baseline testing also establishes a reference point for safety monitoring. Changes in kidney function, liver enzymes, electrolytes, or blood glucose can occur over time, and having pre-treatment values allows for appropriate interpretation. Monitoring helps distinguish medication-related changes from pre-existing conditions and ensures that treatment remains medically appropriate as weight and metabolic markers shift.
In addition, blood work can identify deficiencies that may worsen with appetite suppression, including iron, vitamin B12, vitamin D, and protein status. Addressing these proactively reduces the risk of fatigue, hair loss, muscle loss, and weakness during treatment. GLP-1 medications are most effective and safest when used within a comprehensive, data-driven care plan rather than in isolation.
Dr. Jenn