What is a GLP-1? The Complete Beginner's Guide

You've heard of Ozempic. Maybe Wegovy or Mounjaro too. GLP-1 medications are everywhere right now — but what actually are they, how do they work, and are they right for you? This guide covers everything you need to know before making a decision.

What is a GLP-1?

GLP-1 stands for glucagon-like peptide-1 — a hormone your body naturally produces in your intestines after eating. Its job is to signal your brain that food has arrived: slow down digestion, release insulin, and start feeling full.

GLP-1 receptor agonists are medications that mimic this hormone. They bind to the same receptors in your brain and gut, but do so far more powerfully — and for much longer — than the GLP-1 your body produces naturally. The result is a dramatically reduced appetite, slower gastric emptying, and meaningful weight loss for the majority of people who use them consistently.

How do GLP-1s cause weight loss?

GLP-1 medications work through several mechanisms simultaneously, which is why they're more effective than most previous weight loss drugs:

• Brain signaling: They activate areas of the brain that regulate hunger and satiety, reducing the desire to eat.
• Slower gastric emptying: Food moves more slowly from your stomach to your intestines, keeping you feeling full longer.
• Insulin regulation: They stimulate insulin release when blood sugar rises, helping manage blood sugar without causing dangerous lows.
• Reduced food cravings: Many users report a reduction in "food noise" — the constant background thoughts about eating that drive overconsumption.

The different GLP-1 medications explained

There are several GLP-1 medications available, and the names get confusing fast. Here's a clear breakdown:

Semaglutide vs Tirzepatide — which is better?

Tirzepatide (Zepbound/Mounjaro) works on two receptors — GIP and GLP-1 — while semaglutide works on one. Clinical trial data shows tirzepatide produces modestly greater weight loss on average. However, semaglutide has a longer track record, more real-world data, and is typically cheaper. Both are excellent options. The right choice depends on your health history and what your provider recommends.

What are compounded GLP-1s?

Compounded semaglutide and tirzepatide are versions made by licensed compounding pharmacies rather than the original manufacturers. They use the same active ingredient but are not FDA-reviewed as finished drug products. They're typically 30–60% cheaper than brand-name versions — which is why most telehealth programs use them.

What results can you realistically expect?

Clinical trials show impressive results, but real-world outcomes vary. Here's a realistic picture:

• First 4 weeks: Most people notice reduced appetite. Weight loss is typically modest at lower starting doses.
• Weeks 8–16: As the dose increases, appetite suppression becomes more pronounced. Most people see 5–10% body weight loss in this window.
• Months 6–12: Weight loss continues to accumulate. People following the full protocol see 12–20%+ total body weight loss.
• Beyond 12 months: Many people continue on a maintenance dose. Stopping medication typically leads to regain over time without lifestyle changes.

The most important factor is consistency — taking the medication as prescribed, attending check-ins, and combining it with dietary adjustments (you don't need to diet aggressively, but eating nutritious food helps).

Side effects — what to expect

GLP-1 medications are generally well-tolerated, but side effects — especially early on — are common. The most important thing to know: most side effects are temporary and improve significantly after the first few weeks.

Common side effects (usually temporary)

• Nausea — the most common, usually in the first 4–8 weeks
• Vomiting — less common, usually related to eating too quickly or too much
• Constipation or diarrhea
• Fatigue, especially early on
• Reduced appetite (this is the intended effect, but can feel uncomfortable at first)

Less common but serious side effects

• Pancreatitis — rare, but stop medication and seek care if you have severe abdominal pain
• Gallbladder problems — more common with rapid weight loss
• Possible thyroid effects — GLP-1s carry a warning for thyroid cancer risk in people with a personal or family history of medullary thyroid carcinoma

Do you qualify for a GLP-1 prescription?

General eligibility criteria for weight loss prescriptions:

• BMI of 30 or higher (classified as obese), OR
• BMI of 27 or higher with at least one weight-related health condition such as high blood pressure, Type 2 diabetes, high cholesterol, or sleep apnea
• No personal or family history of medullary thyroid carcinoma
• Not currently pregnant or planning pregnancy
• Not currently taking certain other medications (your provider will review)

Individual telehealth programs may have slightly different criteria. A provider consultation — which is included in every program we recommend — will determine your personal eligibility.

What does it cost?

Cost is one of the most common questions, and the range is wide:

• Brand-name without insurance: $1,300–$1,600/month (Wegovy, Zepbound)
• Brand-name with good insurance: $0–$50/month copay (if covered)
• Telehealth with compounded medication: $89–$299/month — the most common path for most people

Most people without insurance coverage go the telehealth + compounded route. It's significantly cheaper and the clinical outcomes appear comparable based on available real-world data.

How to get started

The most accessible path for most people is through a telehealth program. Here's the typical process:

1. Choose a program — compare based on cost, support level, and medication type
2. Complete an intake form — about 5–10 minutes online, covers your health history and goals
3. Consult with a provider — video call or async review, they determine if you're a good candidate
4. Receive your prescription — if approved, it ships directly to your door within about a week
5. Monthly check-ins — most programs include regular follow-ups to adjust your dose and support your progress