GLP-1 receptor agonists — including semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) — have fundamentally changed what is possible in obesity medicine. These medications achieve weight loss of 15-22% of body weight — outcomes previously only achievable with bariatric surgery.
What are GLP-1 Medications?
GLP-1 (glucagon-like peptide-1) is a hormone naturally produced in the gut after meals. It stimulates insulin secretion, suppresses glucagon, slows gastric emptying, and — critically — acts on the brain to reduce appetite. GLP-1 receptor agonists mimic and amplify these effects at higher concentrations than naturally occur.
The Major GLP-1 Medications Explained
Semaglutide (Ozempic / Wegovy)
- Ozempic — Weekly injection FDA-approved for type 2 diabetes. Average 10-15% body weight reduction. Also proven to reduce cardiovascular events by 20% (SELECT trial)
- Wegovy — Same molecule as Ozempic but FDA-approved for chronic weight management at a higher dose (2.4mg). Average 15-17% body weight loss in STEP trials
Tirzepatide (Mounjaro / Zepbound)
- Dual GIP/GLP-1 receptor agonist — stimulates two hormones instead of one
- Mounjaro — FDA-approved for type 2 diabetes. Superior A1C lowering vs. semaglutide
- Zepbound — FDA-approved for obesity management. Average 20-22% body weight loss in SURMOUNT trials — the highest efficacy of any obesity medication
How Do They Cause Weight Loss?
GLP-1 medications cause weight loss through multiple mechanisms:
- Appetite suppression — Acting on hypothalamic centers in the brain, reducing the desire to eat and increasing satiety signals
- Slowing gastric emptying — Food stays in the stomach longer, maintaining fullness after meals
- Reducing food reward — Many patients report reduced cravings for high-calorie foods specifically
- Improved insulin function — Better glucose metabolism reduces fat storage
Beyond Weight Loss — Remarkable Health Benefits
GLP-1 medications do far more than reduce weight. Research shows:
- Cardiovascular protection — Semaglutide reduced major cardiac events by 20% in people without diabetes (SELECT trial, NEJM 2023)
- Kidney protection — FLOW trial: semaglutide reduced kidney disease progression by 24%
- Type 2 diabetes remission — Many patients achieve A1C normalization, some achieving remission
- Sleep apnea improvement — Tirzepatide reduced AHI (apnea events/hour) by 63% in sleep apnea patients
- Fatty liver disease — Dramatic improvement in non-alcoholic steatohepatitis (NASH)
Who Qualifies for GLP-1 Therapy?
GLP-1 medications are FDA-approved for:
- Adults with BMI ≥30 (obesity)
- Adults with BMI ≥27 plus at least one weight-related health condition (diabetes, hypertension, high cholesterol, sleep apnea, heart disease)
- Adults with type 2 diabetes who need improved glucose control
Common Side Effects
Most side effects are gastrointestinal and occur mainly during dose escalation:
- Nausea, vomiting, diarrhea (usually mild and transient)
- Constipation (more common with tirzepatide)
- Decreased appetite (usually welcome!)
Slow dose escalation dramatically reduces side effect severity. Most patients tolerate these medications well after the titration period.
What About Muscle Loss?
Weight loss with GLP-1 medications includes both fat and lean mass loss (10-40% of total weight lost is lean mass). This is similar to all weight loss interventions. The key mitigation strategies are: adequate protein intake (1.2-1.6g/kg of ideal body weight daily) and resistance exercise during weight loss.
GLP-1 Therapy at Synergy MD Clinic
Dr. Kaura provides medically supervised GLP-1 therapy with careful monitoring, individualized dose titration, nutritional guidance, and ongoing follow-up. We assist with insurance prior authorization and access to manufacturer savings programs.