The Complete GLP-1 Medication Guide for 2026: Semaglutide, Tirzepatide, and Beyond

GLP-1 medications have transformed metabolic medicine. In five years, they've gone from a niche diabetes drug to the most-prescribed weight loss intervention in history, with clinical trial data that rivals bariatric surgery. In 2026, the field is evolving rapidly — new drugs, new evidence, new options.

This guide covers everything you need to know: how these medications work, what's available, what they cost (including how to get them affordably), and how to evaluate which option is right for you.

How GLP-1 Medications Work

GLP-1 stands for glucagon-like peptide-1 — a hormone naturally released by cells in your small intestine after you eat. It signals your brain that you're full, slows the rate at which food empties from your stomach, and stimulates insulin release from the pancreas in a glucose-dependent manner.

GLP-1 medications are synthetic versions of this hormone, modified to last much longer in your body (days to weeks, versus minutes for natural GLP-1). By chronically activating GLP-1 receptors, they produce:

Appetite suppression: GLP-1 receptors in the hypothalamus reduce hunger signals. Most patients describe a dramatic reduction in "food noise" — the constant background thoughts about food and eating that they didn't realize were abnormal until they disappeared.

Gastric emptying delay: Food stays in the stomach longer, extending the mechanical fullness signal after smaller meals.

Improved insulin sensitivity: GLP-1 agonism enhances how muscle and fat cells respond to insulin, improving glucose metabolism even in non-diabetic patients.

Central reward circuit effects: GLP-1 receptors in the brain's dopamine system appear to reduce the reward value of food — particularly hyper-palatable, ultra-processed foods. The compulsive pull toward overeating diminishes at a neurological level.

The Main GLP-1 Medications in 2026

### Semaglutide (Ozempic / Wegovy / Compounded) Mechanism: GLP-1 receptor agonist (single receptor) Dosing: Weekly subcutaneous injection Approved uses: Ozempic for Type 2 diabetes; Wegovy for weight management (BMI ≥30, or ≥27 with comorbidities) Max dose: 2.4mg weekly (Wegovy) Average weight loss: ~15% of body weight (STEP 1 trial, 68 weeks) Brand-name cost: $900-1,200/month Compounded cost at Marrow: $249/month

Semaglutide was the breakthrough. Ozempic's approval for diabetes in 2017 set off a wave of off-label weight loss use that drove the Wegovy approval in 2021. The STEP trials produced landmark data, and the SELECT trial (2023) added cardiovascular outcomes evidence — a 20% reduction in major cardiovascular events in patients with obesity and established cardiovascular disease.

Semaglutide remains the most established GLP-1 medication with the most long-term real-world data.

### Tirzepatide (Mounjaro / Zepbound / Compounded) Mechanism: Dual GIP/GLP-1 receptor agonist (two receptors) Dosing: Weekly subcutaneous injection Approved uses: Mounjaro for Type 2 diabetes; Zepbound for weight management Max dose: 15mg weekly Average weight loss: ~22.5% of body weight (SURMOUNT-1 trial); ~20% vs ~14% vs semaglutide (SURMOUNT-5 head-to-head) Brand-name cost: $1,000-1,300/month Compounded cost at Marrow: $299/month

Tirzepatide's addition of GIP receptor activation (in addition to GLP-1) produces meaningfully greater weight loss on average. The SURMOUNT-1 trial showing 22.5% average weight loss at the highest dose was landmark — numbers that were not achievable with any previous non-surgical intervention.

The direct head-to-head comparison (SURMOUNT-5) confirmed tirzepatide's superiority: patients on tirzepatide lost 47% more weight than those on semaglutide over 72 weeks. For most patients prioritizing weight loss outcomes, tirzepatide is the more effective option.

### Liraglutide (Saxenda) — Legacy Liraglutide was the first GLP-1 approved for weight loss (2014). It requires daily injections (versus weekly for sema and tirz) and produces less weight loss — approximately 5-8% of body weight. It has largely been superseded by weekly options and is now rarely a first-line choice.

### Retatrutide — Coming Soon Retatrutide is a triple receptor agonist (GLP-1 + GIP + glucagon receptor). Phase 2 trials showed average weight loss of 17.5% at 24 weeks — a pace suggesting it may ultimately outperform tirzepatide at longer durations. Phase 3 trials are ongoing. Not expected to be commercially available before 2027.

Compounded GLP-1 Medications

Compounded semaglutide and tirzepatide became legal and widely available during FDA shortage periods. They remain a legal prescription option prepared by FDA-registered 503B compounding pharmacies.

Why compounding exists: Brand-name medications like Wegovy and Zepbound are priced at $900-1,300/month — outside the budget of most patients without insurance coverage. Compounding pharmacies can prepare the same active pharmaceutical ingredient at dramatically lower cost because they're not recouping brand-name R&D and marketing overhead.

Are compounded GLP-1 medications safe? FDA-registered 503B pharmacies are subject to federal oversight and must follow Current Good Manufacturing Practice guidelines. The active ingredient quality is regulated. The risks are comparable to any compounded prescription.

The practical difference for most patients: The same medication, a fraction of the cost, with a prescription from a licensed physician. At Marrow, compounded semaglutide is $249/month and compounded tirzepatide is $299/month — both including physician oversight, all injection supplies, and free shipping.

How to Get a GLP-1 Prescription

### Through a telehealth platform (fastest, most accessible) Telehealth platforms like Marrow allow you to complete an intake form online, have a physician review your health history, and if appropriate, receive a prescription without an in-person visit. Timeline: intake completed in 5 minutes, physician review within 24 hours, medication ships within 3-5 business days.

### Through your primary care physician Many PCPs now prescribe GLP-1 medications. The challenge: prior authorization requirements from insurance are burdensome, appointment availability may be limited, and cost without coverage often remains high.

### Through a weight loss clinic Many in-person weight loss clinics now offer GLP-1 prescriptions, often bundled with monitoring packages. Higher-touch but higher-cost — often $400-600/month including the medication.

Who Qualifies

FDA approval criteria for GLP-1 weight loss medications: - BMI ≥30, OR - BMI ≥27 with at least one weight-related comorbidity (hypertension, Type 2 diabetes, high cholesterol, sleep apnea)

In practice, many physicians will prescribe for patients near these thresholds who have symptoms of metabolic dysfunction, and the [microdosing GLP-1 protocol](/microdosing-glp1) extends the patient profile to motivated individuals seeking metabolic optimization rather than treatment of obesity.

Contraindications: - Personal or family history of medullary thyroid carcinoma - Multiple Endocrine Neoplasia syndrome type 2 (MEN2) - Active pancreatitis - Pregnancy or nursing

Choosing Between Semaglutide and Tirzepatide

The head-to-head data favors tirzepatide for weight loss outcomes. But the choice isn't always obvious:

Choose tirzepatide if: Maximum weight loss is the priority, you're not constrained by the slight cost difference, and you don't have established cardiovascular disease (where semaglutide's SELECT data may be relevant).

Choose semaglutide if: You have cardiovascular disease (stronger outcome data), you've had GI sensitivity with other medications, you want the more-established drug profile, or you're starting lower and may escalate later.

Start semaglutide if you've never tried either; switch to tirzepatide if you plateau on semaglutide — this is a common and effective protocol.

What to Expect in the First 90 Days

• Days 1-30: Appetite begins to shift. Mild nausea possible. Weight loss of 5-10 pounds average.
• Days 30-60: Titration to higher dose. Appetite suppression more pronounced. 10-18 pounds total typical.
• Days 60-90: Establishing in therapeutic dose range. Consistent weekly loss of 0.75-1.5 lbs. 15-25 pounds total achievable.

Maximum results come at 9-18 months. Three months is the beginning, not the endpoint.

The Bottom Line for 2026

GLP-1 medications are the most effective non-surgical weight loss intervention ever developed. The clinical evidence is overwhelming, access has improved dramatically through compounding, and cost is no longer a barrier for most patients.

[Start your GLP-1 prescription at Marrow](/start) — physician review in 24 hours, compounded semaglutide at $249/month, tirzepatide at $299/month.