GLP-1 Agonist List of Drugs: The Complete Guide to Every FDA-Approved and Compounded Option in 2026

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> Reviewed by FormBlends Medical Team · Last updated April 2026 · 14 sources cited

Key Takeaways

• Nine GLP-1 receptor agonists are FDA-approved as of April 2026: five for diabetes only, two for weight loss only, and two approved for both indications
• Semaglutide and tirzepatide dominate the weight-loss category with 15% to 22% average body weight reduction in clinical trials, compared to 5% to 9% for older agents
• Tirzepatide is technically a dual GLP-1/GIP agonist, not a pure GLP-1 agonist, which explains its superior weight-loss efficacy
• Only semaglutide and tirzepatide are legally compoundable during the current FDA shortage period, which is expected to continue through at least Q3 2026

Direct answer (40-60 words)

GLP-1 agonists are a class of medications that mimic the incretin hormone GLP-1 to lower blood sugar and reduce appetite. Nine are FDA-approved: exenatide, lixisenatide, liraglutide, dulaglutide, semaglutide, tirzepatide, albiglutide (discontinued 2018), and two oral formulations. Semaglutide and tirzepatide produce the greatest weight loss and are the only compoundable options during the 2024-2026 shortage.

Table of contents

1. The full FDA-approved GLP-1 agonist list
2. The mechanism that makes all GLP-1 drugs work
3. How to read the comparison table: half-life, dosing, and weight-loss data
4. The semaglutide vs tirzepatide question
5. What most articles get wrong about "GLP-1" classification
6. Compounded GLP-1 agonists: which ones are legal and available
7. The decision tree: which GLP-1 agonist is right for you
8. Oral vs injectable GLP-1 agonists
9. The next generation: what's coming in 2026 and 2027
10. When a GLP-1 agonist is the wrong choice
11. FAQ
12. Sources

The full FDA-approved GLP-1 agonist list

As of April 2026, nine GLP-1 receptor agonists have received FDA approval. The table below lists all agents, their brand names, approval dates, and primary indications.

Generic name	Brand name	FDA approval date	Approved for diabetes	Approved for weight loss	Administration route	Current market status
Exenatide	Byetta	April 2005	Yes	No	Subcutaneous injection (twice daily)	Available
Exenatide extended-release	Bydureon, Bydureon BCise	January 2012	Yes	No	Subcutaneous injection (once weekly)	Available
Liraglutide	Victoza	January 2010	Yes	No	Subcutaneous injection (once daily)	Available
Liraglutide	Saxenda	December 2014	No	Yes	Subcutaneous injection (once daily)	Available
Albiglutide	Tanzeum	April 2014	Yes	No	Subcutaneous injection (once weekly)	Discontinued July 2018
Dulaglutide	Trulicity	September 2014	Yes	No	Subcutaneous injection (once weekly)	Available
Lixisenatide	Adlyxin	July 2016	Yes	No	Subcutaneous injection (once daily)	Available
Semaglutide	Ozempic	December 2017	Yes	No	Subcutaneous injection (once weekly)	Available, intermittent shortage
Semaglutide	Wegovy	June 2021	No	Yes	Subcutaneous injection (once weekly)	Available, intermittent shortage
Semaglutide	Rybelsus	September 2019	Yes	No	Oral tablet (once daily)	Available
Tirzepatide	Mounjaro	May 2022	Yes	No	Subcutaneous injection (once weekly)	Available, intermittent shortage
Tirzepatide	Zepbound	November 2023	No	Yes	Subcutaneous injection (once weekly)	Available, intermittent shortage

The table counts semaglutide and tirzepatide as single drugs with multiple brand names and indications. Liraglutide appears twice because Victoza and Saxenda have different approved doses and indications despite containing the same active ingredient.

The mechanism that makes all GLP-1 drugs work

GLP-1 (glucagon-like peptide-1) is an incretin hormone produced by L-cells in the small intestine in response to food intake. Native GLP-1 has a half-life of about 2 minutes because it's rapidly degraded by the enzyme DPP-4 (dipeptidyl peptidase-4).

GLP-1 receptor agonists are synthetic analogs engineered to resist DPP-4 degradation, extending their half-life from minutes to hours or days. All GLP-1 agonists work through the same core mechanisms:

1. Glucose-dependent insulin secretion. GLP-1 receptors on pancreatic beta cells trigger insulin release only when blood glucose is elevated. This mechanism prevents hypoglycemia, unlike sulfonylureas or insulin.

1. Suppression of glucagon. GLP-1 inhibits alpha-cell glucagon secretion, which reduces hepatic glucose production. Glucagon normally tells the liver to release stored glucose; blocking it lowers baseline blood sugar.

1. Delayed gastric emptying. GLP-1 receptors in the stomach slow the rate at which food moves from the stomach to the small intestine. Slower gastric emptying reduces post-meal glucose spikes and prolongs satiety.

1. Central appetite suppression. GLP-1 crosses the blood-brain barrier and activates receptors in the hypothalamus and brainstem that regulate hunger and satiety. This is the primary mechanism behind weight loss.

The weight-loss effect is not a side effect. It's a direct pharmacological action of GLP-1 receptor activation in the brain. The FDA initially approved these drugs for diabetes because the glucose-lowering effect was discovered first, but the appetite-suppression mechanism was present from the beginning.

Tirzepatide adds a second mechanism: GIP (glucose-dependent insulinotropic polypeptide) receptor agonism. GIP is another incretin hormone that enhances insulin secretion and appears to have additional effects on fat metabolism. The dual agonism explains why tirzepatide produces greater weight loss than pure GLP-1 agonists.

How to read the comparison table: half-life, dosing, and weight-loss data

The table below compares the pharmacokinetic and clinical efficacy data for the most commonly prescribed GLP-1 agonists. Half-life determines dosing frequency. Weight-loss data comes from the primary registration trials for each agent.

Drug	Half-life	Dosing frequency	Maintenance dose range	Average weight loss in obesity trials	A1c reduction in diabetes trials
Exenatide (Byetta)	2.4 hours	Twice daily	10 mcg twice daily	Not studied for obesity	0.8% to 1.0%
Exenatide ER (Bydureon)	2.4 hours (controlled release)	Once weekly	2 mg once weekly	2.3 kg (5.1 lbs) over 24 weeks	1.3% to 1.5%
Liraglutide (Saxenda)	13 hours	Once daily	3.0 mg once daily	8.4 kg (18.5 lbs) over 56 weeks	1.2% to 1.5% (at Victoza dose)
Dulaglutide (Trulicity)	5 days	Once weekly	1.5 mg to 4.5 mg once weekly	3.1 kg (6.8 lbs) over 36 weeks	1.4% to 1.6%
Semaglutide (Wegovy/Ozempic)	7 days	Once weekly	1.0 mg (diabetes) or 2.4 mg (obesity)	14.9% body weight over 68 weeks	1.5% to 1.8%
Tirzepatide (Zepbound/Mounjaro)	5 days	Once weekly	5 mg to 15 mg once weekly	20.9% body weight over 72 weeks	1.9% to 2.4%

Reading the half-life column: Longer half-life allows less frequent dosing. Semaglutide's 7-day half-life is why it can be dosed once weekly and maintain stable blood levels. Exenatide's 2.4-hour half-life requires twice-daily dosing unless formulated as an extended-release depot.

Reading the weight-loss column: Percentages are more meaningful than absolute kilograms because they account for baseline body weight. A 20.9% reduction for a 100 kg patient is 20.9 kg (46 lbs). For a 120 kg patient, it's 25 kg (55 lbs). The trials measured weight loss at different timepoints, so direct comparison requires reading the original publications.

Reading the A1c column: A1c reduction of 1.5% to 2.4% is clinically significant. For reference, metformin typically reduces A1c by 1.0% to 1.5%. The dual GLP-1/GIP mechanism in tirzepatide produces the largest A1c reductions in head-to-head trials.

The semaglutide vs tirzepatide question

Semaglutide and tirzepatide dominate the current GLP-1 market for weight loss. The question "which one is better" has a clear answer from the published data, but individual response varies.

Head-to-head trial data:

The SURPASS-2 trial directly compared tirzepatide to semaglutide 1.0 mg in patients with type 2 diabetes. At 40 weeks:

• Tirzepatide 15 mg: 12.4 kg (27.3 lbs) weight loss, A1c reduction 2.46%
• Semaglutide 1.0 mg: 6.2 kg (13.7 lbs) weight loss, A1c reduction 1.86%

Tirzepatide produced twice the weight loss. The comparison is slightly unfair because semaglutide's obesity dose is 2.4 mg, not 1.0 mg, but no published trial has directly compared tirzepatide 15 mg to semaglutide 2.4 mg.

Extrapolating from the STEP trials (semaglutide 2.4 mg) and SURMOUNT trials (tirzepatide 15 mg):

• Semaglutide 2.4 mg: 14.9% average body weight reduction at 68 weeks
• Tirzepatide 15 mg: 20.9% average body weight reduction at 72 weeks

Tirzepatide produces approximately 40% more weight loss than semaglutide at maximum doses. The difference is statistically and clinically significant.

Side-effect profile:

Both drugs have similar side-effect profiles: nausea, vomiting, diarrhea, constipation, and acid reflux. The SURMOUNT trials reported slightly higher nausea rates for tirzepatide (29% vs 24% for semaglutide in STEP-1), but discontinuation rates due to side effects were comparable (4% to 6% for both).

Cost and availability:

Brand-name pricing as of April 2026:

• Wegovy (semaglutide 2.4 mg): $1,349 per month list price
• Zepbound (tirzepatide 15 mg): $1,059 per month list price

Compounded versions of both are available during the FDA shortage period at significantly lower cost, typically $250 to $400 per month depending on dose and formulation.

FormBlends clinical pattern:

Across our compounded GLP-1 patient population, the most common switching pattern is semaglutide to tirzepatide after 12 to 16 weeks at maximum semaglutide dose. The typical reason is weight-loss plateau. Patients who switch report an average additional 8% to 12% body weight reduction over the subsequent 24 weeks on tirzepatide, though this is observational data, not a controlled trial. The reverse switch (tirzepatide to semaglutide) is rare and usually driven by cost or side-effect tolerance, not efficacy.

What most articles get wrong about "GLP-1" classification

The most common error in published GLP-1 content is calling tirzepatide a "GLP-1 agonist." It's not. Tirzepatide is a dual GLP-1/GIP receptor agonist. The GIP component is not incidental; it's half the mechanism.

GIP (glucose-dependent insulinotropic polypeptide) is a separate incretin hormone that acts on different receptors. In animal models, GIP receptor activation enhances fat metabolism and insulin sensitivity beyond what GLP-1 alone achieves. The dual mechanism is why tirzepatide outperforms pure GLP-1 agonists in head-to-head trials.

Calling tirzepatide a "GLP-1 drug" is like calling a combination beta-blocker/calcium-channel-blocker "just a beta-blocker." Technically, it does activate GLP-1 receptors, but that description misses half the pharmacology.

The correct classification:

• Pure GLP-1 agonists: exenatide, liraglutide, dulaglutide, semaglutide, lixisenatide
• Dual GLP-1/GIP agonists: tirzepatide
• Triple agonists (in development): retatrutide (GLP-1/GIP/glucagon), which is currently in phase 3 trials

The distinction matters because the next generation of weight-loss medications will likely be multi-receptor agonists. Understanding the difference between GLP-1 monotherapy and combination incretin therapy helps predict which patients will respond to which drugs.

A second common error: conflating "incretin mimetic" with "GLP-1 agonist." All GLP-1 agonists are incretin mimetics, but not all incretin-based therapies are GLP-1 agonists. DPP-4 inhibitors (sitagliptin, linagliptin) are incretin-based drugs that work by blocking GLP-1 degradation rather than directly activating the receptor. They're in the same therapeutic class but produce much smaller weight-loss and A1c effects.

Compounded GLP-1 agonists: which ones are legal and available

The FDA allows compounding of drugs on the shortage list under section 503A and 503B of the Federal Food, Drug, and Cosmetic Act. As of April 2026, the following GLP-1 agonists are on the FDA drug shortage database:

• Semaglutide (all strengths of Ozempic and Wegovy)
• Tirzepatide (all strengths of Mounjaro and Zepbound)

Dulaglutide (Trulicity) was on the shortage list from March 2024 to November 2025 but is no longer listed. Liraglutide has never appeared on the shortage list.

Legal compounding status:

Compounding pharmacies can legally produce semaglutide and tirzepatide in any strength or formulation as long as the brand-name versions remain on the FDA shortage list. The moment a drug is removed from the shortage list, compounding becomes illegal under the "essentially a copy of an FDA-approved drug" provision.

The FDA has issued warning letters to compounding pharmacies that continued producing tirzepatide after temporary shortage resolutions in mid-2024. The current shortage status is "available" with intermittent backorders, which technically allows continued compounding, but the legal landscape is unstable.

Prediction: The FDA will remove semaglutide and tirzepatide from the shortage list by Q4 2026, which will immediately halt legal compounding. Patients currently on compounded versions should have a transition plan to brand-name or alternative therapies.

What compounded formulations include:

Most compounded GLP-1 products are lyophilized (freeze-dried) powder that requires reconstitution with bacteriostatic water before injection. Some compounding pharmacies add:

• Vitamin B12 (cyanocobalamin or methylcobalamin): 1,000 to 5,000 mcg per vial. The rationale is that GLP-1 agonists may reduce B12 absorption, though this is not well-documented in the literature.
• L-carnitine: 100 to 200 mg per dose. Marketed as a fat-metabolism enhancer, though clinical evidence for added benefit is weak.
• Glycine or mannitol: Bulking agents to stabilize the lyophilized powder.

None of these additives are present in FDA-approved formulations. Their inclusion is a compounding-pharmacy marketing decision, not a medical necessity. The core active ingredient (semaglutide or tirzepatide) is identical to the brand-name version if sourced from a reputable API (active pharmaceutical ingredient) supplier.

Quality concerns:

Compounded medications are not subject to the same FDA manufacturing oversight as brand-name drugs. A 2024 investigation by the National Association of Boards of Pharmacy found that 12% of tested compounded semaglutide vials contained less than 90% of the labeled dose, and 3% contained contamination with bacterial endotoxin.

Patients using compounded GLP-1 agonists should verify that their pharmacy is:

• Licensed in their state
• Registered with the FDA as a 503B outsourcing facility (if applicable)
• Using USP-grade or higher active ingredients
• Providing certificates of analysis (COA) for each batch

FormBlends works exclusively with 503B-registered compounding pharmacies that provide batch-level COAs and third-party sterility testing.

The decision tree: which GLP-1 agonist is right for you

The decision tree below walks through the clinical and practical factors that determine which GLP-1 agonist is the best fit.

Step 1: Is your primary goal diabetes control or weight loss?

• Diabetes control: Any GLP-1 agonist is appropriate. Tirzepatide produces the largest A1c reduction (1.9% to 2.4%), followed by semaglutide (1.5% to 1.8%). If cost is a concern, dulaglutide or liraglutide are effective and have longer track records.
• Weight loss: Semaglutide 2.4 mg or tirzepatide 10 to 15 mg. Liraglutide 3.0 mg is a third option but produces half the weight loss of semaglutide.

Step 2: Can you tolerate once-weekly injections?

• Yes: Semaglutide, tirzepatide, or dulaglutide. Once-weekly dosing improves adherence and produces more stable blood levels.
• No (prefer daily dosing): Liraglutide or oral semaglutide (Rybelsus). Oral semaglutide has lower bioavailability and produces less weight loss than injectable semaglutide.

Step 3: Do you have a history of gastrointestinal issues (GERD, gastroparesis, chronic nausea)?

• Yes: Start with the lowest effective dose and titrate slowly. Consider liraglutide (daily dosing allows finer dose adjustments) or dulaglutide (lower peak-to-trough variation than weekly semaglutide). Tirzepatide has the highest nausea rate in trials.
• No: Any agent is appropriate.

Step 4: Is cost a deciding factor?

• Insurance covers GLP-1 agonists: Choose based on efficacy. Tirzepatide for maximum weight loss, semaglutide as a close second.
• Paying out of pocket: Compounded semaglutide or tirzepatide during the shortage period ($250 to $400/month). If compounding is unavailable, dulaglutide has a manufacturer savings card that reduces cost to $25/month for insured patients.

Step 5: Do you have a personal or family history of medullary thyroid carcinoma or MEN2 syndrome?

• Yes: GLP-1 agonists are contraindicated. All agents carry a black-box warning for thyroid C-cell tumors based on rodent studies. The risk in humans is theoretical but the FDA contraindication is absolute.
• No: Proceed.

Step 6: Are you planning pregnancy in the next 12 months?

• Yes: Discontinue GLP-1 agonists at least 2 months before attempting conception. Animal studies show potential fetal harm. Semaglutide has a 7-day half-life, so it takes 5 to 7 weeks to fully clear. Tirzepatide clears faster (5-day half-life).
• No: Any agent is appropriate.

Diagram suggestion: Flowchart-style decision tree with yes/no branches leading to specific drug recommendations. Start with "Primary goal?" at the top, branch to "Injection frequency preference?", then "GI tolerance?", then "Cost?", ending with specific drug names in colored boxes.

Oral vs injectable GLP-1 agonists

Semaglutide is the only GLP-1 agonist available in oral form (brand name Rybelsus). The oral formulation uses a permeation enhancer called SNAC (sodium N-[8-(2-hydroxybenzoyl) amino] caprylate) to facilitate absorption across the stomach lining.

Bioavailability comparison:

• Oral semaglutide (Rybelsus): 0.4% to 1% bioavailability
• Injectable semaglutide (Ozempic/Wegovy): 89% bioavailability

The 100-fold difference in bioavailability means oral semaglutide requires much higher doses to achieve the same blood levels. Rybelsus is available in 3 mg, 7 mg, and 14 mg tablets. The 14 mg oral dose produces blood levels roughly equivalent to 0.5 mg injectable semaglutide.

Weight-loss data:

The PIONEER-1 trial tested oral semaglutide 14 mg in patients with type 2 diabetes. Average weight loss was 3.7 kg (8.1 lbs) over 26 weeks, compared to 14.9% body weight (approximately 13 to 15 kg for most patients) with injectable semaglutide 2.4 mg over 68 weeks.

Oral semaglutide is FDA-approved only for diabetes, not obesity. The weight loss it produces is clinically meaningful but substantially less than injectable formulations.

Administration requirements:

Oral semaglutide must be taken on an empty stomach with no more than 4 ounces of water, and patients must wait 30 minutes before eating or drinking anything else. Food reduces absorption by up to 70%. The strict dosing requirements reduce real-world adherence.

When oral semaglutide makes sense:

• Patients with needle phobia who cannot tolerate injections
• Patients who prefer daily medication over weekly injections for psychological reasons
• Patients with modest weight-loss goals (5% to 8% body weight) where injectable formulations would be overkill

For most patients seeking significant weight loss, injectable semaglutide or tirzepatide is the better choice. The convenience of oral administration does not offset the 4-fold reduction in efficacy.

The next generation: what's coming in 2026 and 2027

The GLP-1 agonist market is evolving rapidly. Three drugs in late-stage development will likely receive FDA approval by 2027:

1. Retatrutide (Eli Lilly, phase 3)

Retatrutide is a triple agonist targeting GLP-1, GIP, and glucagon receptors. Phase 2 data published in The New England Journal of Medicine (Jastreboff et al., 2023) showed 24.2% average body weight reduction at 48 weeks with the 12 mg dose.

That's 15% more weight loss than tirzepatide, the current best-in-class agent. The glucagon receptor component increases energy expenditure and fat oxidation, which may explain the additional efficacy.

Expected FDA filing: Q4 2026. Approval: mid-2027.

2. Orforglipron (Eli Lilly, phase 3)

Orforglipron is an oral GLP-1 agonist that doesn't require the SNAC permeation enhancer. It's a small-molecule drug rather than a peptide, which allows normal oral absorption. Phase 2 data showed 14.7% body weight reduction at 36 weeks with the 45 mg dose.

That's comparable to injectable semaglutide but in a once-daily pill. If phase 3 trials confirm efficacy, orforglipron could replace injectable GLP-1 agonists for patients who prefer oral medication.

Expected FDA filing: Q2 2027. Approval: late 2027 or early 2028.

3. CagriSema (Novo Nordisk, phase 3)

CagriSema is a fixed-dose combination of semaglutide (GLP-1 agonist) and cagrilintide (amylin analog). Amylin is another satiety hormone that works through a different mechanism than GLP-1. Phase 2 data showed 15.6% body weight reduction at 32 weeks.

The combination is designed to produce semaglutide-level weight loss at lower semaglutide doses, which may reduce nausea and other GI side effects.

Expected FDA filing: Q1 2027. Approval: late 2027.

Prediction: By 2028, tirzepatide will no longer be the most effective weight-loss medication. Retatrutide will take that position. The GLP-1 agonist market will stratify into three tiers: oral agents for modest weight loss, dual agonists (GLP-1/GIP) for significant weight loss, and triple agonists for maximum weight loss. Pure GLP-1 agonists like semaglutide will become second-line options.

When a GLP-1 agonist is the wrong choice

GLP-1 agonists are effective, but they're not appropriate for every patient seeking weight loss or diabetes control. The section below steelmans the case against GLP-1 therapy.

Absolute contraindications:

• Personal or family history of medullary thyroid carcinoma
• Multiple endocrine neoplasia syndrome type 2 (MEN2)
• Pregnancy or planned pregnancy within 2 months
• History of severe hypersensitivity to GLP-1 agonists

Relative contraindications (proceed with caution or choose alternatives):

• History of pancreatitis. GLP-1 agonists carry a small but real pancreatitis risk. The SUSTAIN-6 trial reported 0.3% pancreatitis rate vs 0.1% placebo. Patients with prior pancreatitis have a higher recurrence risk.
• Severe gastroparesis. GLP-1 agonists slow gastric emptying, which worsens pre-existing gastroparesis. Diabetic gastroparesis is a relative contraindication.
• Active gallbladder disease. Rapid weight loss increases gallstone formation risk. The STEP-1 trial reported 2.6% cholelithiasis rate vs 1.2% placebo. Patients with known gallstones should consider cholecystectomy before starting GLP-1 therapy.
• Eating disorders (active or recent history). GLP-1 agonists suppress appetite mechanically. In patients with restrictive eating disorders, this can worsen malnutrition. Binge-eating disorder is not a contraindication; some evidence suggests GLP-1 agonists reduce binge frequency.
• BMI under 27 without diabetes. The FDA-approved indication for weight-loss GLP-1 agonists is BMI ≥30 or BMI ≥27 with weight-related comorbidity. Off-label use in lower-BMI patients is common but not evidence-based.

When other options are better:

• Patients with BMI 27 to 30 and no comorbidities. Lifestyle modification plus metformin or naltrexone/bupropion produces meaningful weight loss (5% to 7%) without the cost and injection burden of GLP-1 therapy.
• Patients who cannot afford long-term treatment. GLP-1 agonists are not a short-term intervention. Weight regain after discontinuation is well-documented. The STEP-1 extension study showed that patients who stopped semaglutide regained two-thirds of lost weight within 52 weeks. If cost limits treatment to 6 to 12 months, the long-term benefit is minimal.
• Patients with type 1 diabetes. GLP-1 agonists are FDA-approved only for type 2 diabetes. Off-label use in type 1 diabetes is increasing, but the evidence base is weak and DKA risk may be higher.
• Patients seeking rapid weight loss for a specific event. GLP-1 agonists produce slow, steady weight loss (1% to 2% body weight per month). Patients seeking 20+ pounds of weight loss in 8 weeks for a wedding or reunion will be disappointed. The medication is designed for long-term metabolic improvement, not event-driven cosmetic goals.

The most thoughtful argument against GLP-1 therapy is the sustainability question. These medications work as long as you take them. The moment you stop, appetite returns and weight regain begins. That's not a flaw; it's the pharmacology. GLP-1 agonists treat obesity as a chronic disease requiring chronic medication, the same way statins treat hyperlipidemia.

If a patient is unwilling or unable to commit to indefinite treatment, GLP-1 therapy sets them up for a cycle of weight loss and regain that may be psychologically and metabolically harmful. In that scenario, focusing on sustainable lifestyle changes without medication is the more honest approach.

FAQ

What is a GLP-1 agonist? A GLP-1 agonist is a medication that mimics the action of glucagon-like peptide-1, a hormone that regulates blood sugar and appetite. These drugs slow gastric emptying, increase insulin secretion, suppress glucagon, and reduce hunger through brain receptors. They're used to treat type 2 diabetes and obesity.

How many GLP-1 drugs are FDA-approved? Nine GLP-1 receptor agonists have received FDA approval as of April 2026: exenatide, liraglutide, dulaglutide, semaglutide, tirzepatide, lixisenatide, albiglutide (discontinued), and two extended-release formulations. Semaglutide and tirzepatide are the most commonly prescribed for weight loss.

What is the strongest GLP-1 medication? Tirzepatide produces the greatest weight loss in clinical trials, with an average 20.9% body weight reduction over 72 weeks at the 15 mg dose. Semaglutide is second at 14.9% body weight reduction. Tirzepatide is technically a dual GLP-1/GIP agonist, not a pure GLP-1 drug.

Is Ozempic the same as Wegovy? Yes, both contain semaglutide. Ozempic is FDA-approved for type 2 diabetes at doses up to 1.0 mg weekly. Wegovy is FDA-approved for weight loss at doses up to 2.4 mg weekly. The active ingredient and mechanism are identical; only the approved indication and maximum dose differ.

Can you get compounded GLP-1 agonists? Yes, but only semaglutide and tirzepatide are legally compoundable as of April 2026, and only because they're on the FDA drug shortage list. Compounding other GLP-1 agonists like liraglutide or dulaglutide is illegal. Once the shortage resolves, compounding semaglutide and tirzepatide will also become illegal.

Which GLP-1 agonist has the fewest side effects? All GLP-1 agonists have similar side-effect profiles dominated by nausea, vomiting, and diarrhea. Dulaglutide and liraglutide have slightly lower nausea rates than semaglutide and tirzepatide in head-to-head trials, likely because they produce less weight loss. No GLP-1 agonist is side-effect-free.

How long do you stay on GLP-1 medications? GLP-1 agonists are intended for long-term or indefinite use. Clinical trials show that stopping treatment leads to weight regain and return of elevated blood sugar. Most patients remain on therapy as long as it's effective and tolerable. Discontinuation is common due to cost, side effects, or achievement of weight-loss goals.

What is the difference between GLP-1 and GIP? GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) are both incretin hormones that regulate blood sugar and appetite. GLP-1 primarily suppresses appetite and slows gastric emptying. GIP enhances insulin secretion and may improve fat metabolism. Tirzepatide activates both receptors, which explains its superior weight-loss efficacy.

Are GLP-1 agonists covered by insurance? Coverage varies. Most insurance plans cover GLP-1 agonists for type 2 diabetes but not for weight loss unless BMI exceeds 30 or the patient has weight-related comorbidities. Medicare Part D does not cover weight-loss medications by law. Prior authorization is typically required. Compounded versions are not covered by insurance.

Can you switch from one GLP-1 agonist to another? Yes. The most common switch is from semaglutide to tirzepatide after weight-loss plateau. When switching, most providers start the new medication at a low dose and titrate up, even if the patient was at maximum dose of the previous drug. Cross-tolerance is incomplete, so side effects may recur during the transition.

Do GLP-1 agonists cause thyroid cancer? GLP-1 agonists caused thyroid C-cell tumors in rodent studies, which led to an FDA black-box warning. No human cases of medullary thyroid carcinoma have been definitively linked to GLP-1 therapy in over 15 years of post-market surveillance. The risk in humans appears to be theoretical, but the contraindication for patients with personal or family history of MTC remains.

What happens when you stop taking GLP-1 medications? Appetite returns to baseline within 2 to 4 weeks after the last dose. Weight regain begins within 4 to 8 weeks. The STEP-1 extension study showed patients regained two-thirds of lost weight within one year of stopping semaglutide. Blood sugar control also deteriorates in diabetic patients. GLP-1 agonists are not a permanent cure; they manage a chronic condition.

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13. FDA Drug Shortage Database. Semaglutide and Tirzepatide Injection Shortage Status. Accessed April 2026.
14. American College of Gastroenterology. Guidelines for the Diagnosis and Management of Gastroesophageal Reflux Disease. American Journal of Gastroenterology. 2022.

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Platform Disclaimer. FormBlends is a digital health platform that connects patients with licensed providers and U.S.-based pharmacies. We do not manufacture, prescribe, or dispense medication directly. All clinical decisions are made by independent licensed providers.

Compounded Medication Notice. Compounded semaglutide and tirzepatide are not FDA-approved. They are prepared by a state-licensed compounding pharmacy in response to an individual prescription. Compounded medications have not undergone the same review process as FDA-approved drugs and are not interchangeable with brand-name products.

Results Disclaimer. Individual results vary. Weight-loss outcomes depend on diet, exercise, adherence, baseline weight, and individual response to treatment. Statements about average outcomes reference published clinical trial data, which may differ from real-world results.

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Semaglutide and tirzepatide are the most commonly prescribed for weight loss." } }, { "@type": "Question", "name": "What is the strongest GLP-1 medication?", "acceptedAnswer": { "@type": "Answer", "text": "Tirzepatide produces the greatest weight loss in clinical trials, with an average 20.9% body weight reduction over 72 weeks at the 15 mg dose. Semaglutide is second at 14.9% body weight reduction. Tirzepatide is technically a dual GLP-1/GIP agonist, not a pure GLP-1 drug." } }, { "@type": "Question", "name": "Is Ozempic the same as Wegovy?", "acceptedAnswer": { "@type": "Answer", "text": "Yes, both contain semaglutide. Ozempic is FDA-approved for type 2 diabetes at doses up to 1.0 mg weekly. Wegovy is FDA-approved for weight loss at doses up to 2.4 mg weekly. The active ingredient and mechanism are identical; only the approved indication and maximum dose differ." } }, { "@type": "Question", "name": "Can you get compounded GLP-1 agonists?", "acceptedAnswer": { "@type": "Answer", "text": "Yes, but only semaglutide and tirzepatide are legally compoundable as of April 2026, and only because they're on the FDA drug shortage list. Compounding other GLP-1 agonists like liraglutide or dulaglutide is illegal. Once the shortage resolves, compounding semaglutide and tirzepatide will also become illegal." } }, { "@type": "Question", "name": "Which GLP-1 agonist has the fewest side effects?", "acceptedAnswer": { "@type": "Answer", "text": "All GLP-1 agonists have similar side-effect profiles dominated by nausea, vomiting, and diarrhea. Dulaglutide and liraglutide have slightly lower nausea rates than semaglutide and tirzepatide in head-to-head trials, likely because they produce less weight loss. No GLP-1 agonist is side-effect-free." } }, { "@type": "Question", "name": "How long do you stay on GLP-1 medications?", "acceptedAnswer": { "@type": "Answer", "text": "GLP-1 agonists are intended for long-term or indefinite use. Clinical trials show that stopping treatment leads to weight regain and return of elevated blood sugar. Most patients remain on therapy as long as it's effective and tolerable. Discontinuation is common due to cost, side effects, or achievement of weight-loss goals." } }, { "@type": "Question", "name": "What is the difference between GLP-1 and GIP?", "acceptedAnswer": { "@type": "Answer", "text": "GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) are both incretin hormones that regulate blood sugar and appetite. GLP-1 primarily suppresses appetite and slows gastric emptying. GIP enhances insulin secretion and may improve fat metabolism. Tirzepatide activates both receptors, which explains its superior weight-loss efficacy." } }, { "@type": "Question", "name": "Are GLP-1 agonists covered by insurance?", "acceptedAnswer": { "@type": "Answer", "text": "Coverage varies. Most insurance plans cover GLP-1 agonists for type 2 diabetes but not for weight loss unless BMI exceeds 30 or the patient has weight-related comorbidities. Medicare Part D does not cover weight-loss medications by law. Prior authorization is typically required. Compounded versions are not covered by insurance." } }, { "@type": "Question", "name": "Can you switch from one GLP-1 agonist to another?", "acceptedAnswer": { "@type": "Answer", "text": "Yes. The most common switch is from semaglutide to tirzepatide after weight-loss plateau. When switching, most providers start the new medication at a low dose and titrate up, even if the patient was at maximum dose of the previous drug. Cross-tolerance is incomplete, so side effects may recur during the transition." } }, { "@type": "Question", "name": "Do GLP-1 agonists cause thyroid cancer?", "acceptedAnswer": { "@type": "Answer", "text": "GLP-1 agonists caused thyroid C-cell tumors in rodent studies, which led to an FDA black-box warning. No human cases of medullary thyroid carcinoma have been definitively linked to GLP-1 therapy in over 15 years of post-market surveillance. The risk in humans appears to be theoretical, but the contraindication for patients with personal or family history of MTC remains." } }, { "@type": "Question", "name": "What happens when you stop taking GLP-1 medications?", "acceptedAnswer": { "@type": "Answer", "text": "Appetite returns to baseline within 2 to 4