GLP-1 Guides
Semaglutide

Semaglutide 101: The Complete Beginner's Guide

5 min read Updated Dec 2025

What Is Semaglutide?

Semaglutide is a GLP-1 receptor agonist—a medication that mimics a hormone your body naturally produces. It was originally developed for Type 2 diabetes but became a breakthrough weight loss treatment when clinical trials showed dramatic results.

Brand names include Wegovy (FDA-approved for weight loss) and Ozempic (approved for diabetes, used off-label for weight). Compounded semaglutide contains the same active ingredient, prepared by licensed pharmacies.

15%
Average weight loss in trials
1x
Weekly injection
86%
Lost 5%+ body weight

How Does It Work?

Semaglutide works through four main pathways:

1. Brain signals: It acts on your hypothalamus to reduce hunger signals and increase satiety signals. You feel genuinely satisfied with less food.

2. Slower digestion: Food stays in your stomach longer, creating a prolonged feeling of fullness after meals.

3. "Food noise" reduction: Many users report that the constant mental chatter about food—planning meals, fighting cravings—goes quiet. This is often described as the most life-changing effect.

4. Blood sugar regulation: It helps your body release insulin more effectively, keeping blood sugar stable and reducing energy crashes.

Clinical Trial Results

The STEP trials established semaglutide's effectiveness:

Trial Population Result
STEP 1 Adults without diabetes 14.9% weight loss vs 2.4% placebo
STEP 2 Adults with Type 2 diabetes 9.6% weight loss vs 3.4% placebo
STEP 5 2-year follow-up 15.2% maintained at 2 years
STEP TEENS Adolescents 12-17 16.1% BMI reduction

Dosing Schedule

Semaglutide follows a titration schedule—you start low and increase gradually:

Important: The first 8 weeks are for adjustment, not results. Don't panic if you don't see dramatic changes at 0.25 or 0.5 mg—that's expected.

Side Effects

Most common (and usually temporary):

Serious risks (rare): Pancreatitis, gallbladder issues, and a black-box warning about thyroid C-cell tumors (observed in rodent studies). Anyone with personal or family history of medullary thyroid cancer should not take semaglutide.

Who Should Take Semaglutide?

Good candidates:

Not appropriate for:

Semaglutide vs Tirzepatide

Tirzepatide (Zepbound/Mounjaro) is the newer option, targeting two receptors instead of one. In head-to-head trials, tirzepatide produced about 47% more weight loss. However, semaglutide is more affordable (especially compounded), has more long-term safety data, and works extremely well for most people.

Many people start with semaglutide and only consider switching if they plateau.

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