GLP-1 for Weight Loss: The Complete Guide

What Are GLP-1 Medications?

GLP-1 (glucagon-like peptide-1) medications are a class of drugs originally developed for type 2 diabetes that have proven remarkably effective for weight loss. You might know them by brand names like Ozempic, Wegovy, Mounjaro, or Zepbound.

Here's the simple version: GLP-1 is a hormone your gut naturally produces after eating. It tells your brain "I'm full" and slows down digestion. These medications are synthetic versions of that hormone, but they stick around much longer—giving you that "full" feeling for days instead of minutes.

How Do They Work?

GLP-1 medications work through multiple mechanisms:

• Reduces appetite - Acts on brain regions that control hunger, making you feel full with less food
• Slows stomach emptying - Food stays in your stomach longer, extending that satisfied feeling
• Regulates blood sugar - Increases insulin when needed, decreases glucagon (a hormone that raises blood sugar)
• Decreases food noise - Many users report thinking about food less often throughout the day

Semaglutide vs. Tirzepatide: What's the Difference?

Bottom line: Tirzepatide works on two hormone pathways instead of one, leading to slightly better weight loss results (about 3-5% more on average). Both are weekly injections you do yourself at home with a small pen needle.

How Much Weight Will I Lose?

Clinical trials show impressive results, but real-world outcomes vary:

• Semaglutide 2.4mg (Wegovy): Average 15-17% body weight loss over 68 weeks. Some participants lost over 20%.
• Tirzepatide (Zepbound): Average 16-22% body weight loss over 72 weeks, with some reaching 25%+.
• Real-world data: Actual results tend to be somewhat lower—expect 10-15% weight loss as more realistic.

Common Side Effects

Let's be honest: most people experience side effects, especially in the first few weeks. The good news is they usually improve over time.

Very Common (40-65% of users):

• Nausea - Reported by 20-44% depending on dose and medication
• Diarrhea - Affects 5-12% of users
• Constipation - Common as digestion slows
• Vomiting - Occurs in 3-12% of users
• Stomach pain/bloating - Especially after eating too much

Less Common but Important:

• Fatigue and weakness (often from eating less)
• Headaches
• Dizziness
• Acid reflux/heartburn

Rare but Serious:

• Gallbladder problems (particularly gallstones)
• Pancreatitis (inflammation of pancreas)
• Thyroid tumors (seen in animal studies, unclear in humans)

About 10% of people stop taking GLP-1s due to side effects, mostly GI issues. The key is starting at a low dose and increasing gradually.

Brand-Name vs. Compounded: What's the Difference?

This is crucial to understand because it affects both price and what you're actually getting:

Brand-Name (FDA-Approved)

• Ozempic, Wegovy, Mounjaro, Zepbound - Made by Novo Nordisk or Eli Lilly
• FDA-approved with rigorous testing and quality control
• Exact dosing, consistent quality batch-to-batch
• Cost: $1,000-1,800/month without insurance

Compounded (Not FDA-Approved)

• Made by compounding pharmacies - custom-mixed medications
• Not FDA-approved - No safety/effectiveness review by FDA
• May use semaglutide salts instead of base semaglutide
• Quality varies by pharmacy
• Cost: $99-299/month (much cheaper!)

Who Should (and Shouldn't) Take GLP-1s?

Good Candidates:

• BMI ≥30 (obese), or
• BMI ≥27 (overweight) with weight-related health conditions
• Have struggled with diet and exercise alone
• Can commit to weekly injections
• Can afford ongoing costs (these aren't short-term)

Not Recommended For:

• Personal or family history of medullary thyroid cancer
• Multiple Endocrine Neoplasia syndrome type 2
• Pregnant or planning pregnancy
• History of pancreatitis
• Severe gastroparesis (stomach emptying issues)

How Much Does It Cost?

This is where cash-pay options shine. Without insurance, here's what you're looking at:

What to Expect: The Timeline

The Biggest Questions People Have

Do I have to take it forever?

That's the million-dollar question. Clinical data shows most people regain 2/3 of lost weight within a year of stopping. Think of it like treating high blood pressure—many people need ongoing treatment.

The strategy: Use GLP-1s to lose weight while building sustainable habits (protein-rich diet, strength training, stress management). Some can then transition to maintenance doses or stop entirely, but there's no guarantee.

Will insurance cover it?

Maybe. Insurance coverage for weight loss specifically is spotty. Ozempic is only FDA-approved for diabetes (but prescribed off-label for weight loss). Wegovy and Zepbound are approved for weight loss but many insurers don't cover them or require prior authorization.

This is why cash-pay telehealth options have exploded—predictable $199-499/month is often easier than fighting insurance.

Are compounded versions safe?

Compounded medications haven't gone through FDA approval, which means there's less oversight. However, reputable compounding pharmacies still follow safety standards. The main concerns:

• Dosing consistency may vary slightly batch-to-batch
• Some use semaglutide salts instead of base semaglutide (different formulation)
• No long-term safety data for compounded versions specifically
• Legal availability is now uncertain after shortage ended

What happens if I eat too much on GLP-1s?

You'll regret it. Because these medications slow stomach emptying, eating too much leads to intense nausea, vomiting, and discomfort that can last hours. Most people quickly learn their new, much smaller capacity.

Comparing Your Options

If you're considering GLP-1s for weight loss, here are your main paths:

Tips for Success

1. Start low, go slow - Don't rush dose increases even if you're eager for faster results
2. Prioritize protein - With reduced appetite, hitting 80-100g protein/day prevents muscle loss
3. Stay hydrated - Easy to forget to drink when not hungry
4. Lift weights - Preserve muscle mass during rapid weight loss
5. Plan for maintenance - Build habits now for when/if you stop the medication

Common Mistakes to Avoid

• Eating too much too fast - Learn your new capacity; smaller plates help
• Not eating enough protein - Muscle loss accelerates without adequate protein
• Stopping abruptly - Appetite roars back; taper if possible
• Ignoring side effects - Report severe/persistent issues to your provider
• Skipping strength training - Cardio is great but weights preserve muscle

The Bottom Line

GLP-1 medications are genuinely effective weight-loss tools—the data is clear on that. They work by making it physically easier to eat less, which is why they succeed where willpower alone often fails.

But they're not without tradeoffs: weekly injections, significant side effects for many people, high ongoing costs, and weight regain if you stop. They're a tool, not a cure.

Best candidates: People with 40+ lbs to lose who have tried traditional methods, can afford ongoing treatment, and are committed to building sustainable habits alongside medication.