Saxenda vs Mounjaro: Mounjaro 22.5% Loss vs Saxenda 8% – Head-to-Head Analysis

Mounjaro dominates Saxenda across every major metric: 22.5% body weight loss vs 8%, once-weekly injection vs daily injection, and dual GLP-1/GIP mechanism vs single GLP-1.

Both Saxenda and Mounjaro are prescription medications designed to support weight management by reducing appetite and helping patients lose weight when combined with lifestyle changes. However, clinical trial data shows Mounjaro delivers roughly 2.6 times the weight loss results of Saxenda, with significantly fewer injections per year. 

These two drugs represent different generations of weight loss medications: Saxenda, made by the Danish pharmaceutical company Novo Nordisk, was one of the first GLP-1 receptor agonists approved for weight management, while Mounjaro (by Eli Lilly) is a newer dual-action medication that also targets GIP receptors for enhanced appetite control and metabolic support.

TL;DR

• Mounjaro (tirzepatide) significantly outperforms Saxenda (liraglutide) for weight loss. 
• In clinical trials, participants on the highest dose of Mounjaro lost an average of 22.5% of their body weight over 72 weeks, compared to approximately 8% with Saxenda over 56 weeks. 
• Mounjaro is a dual GIP and GLP-1 receptor agonist requiring only a once-weekly injection, while Saxenda is a GLP-1-only agonist taken as a daily injection. 
• Mounjaro also costs less per month without insurance (approximately $1,000-1,100 vs $1,349 for Saxenda). 
• Both medications require a reduced-calorie diet and increased physical activity and a healthcare provider should guide your choice based on your medical history, body mass index, and weight loss goals.

Saxenda vs Mounjaro Mechanism Differences

Both Saxenda and Mounjaro mimic the actions of GLP-1, a naturally occurring hormone that helps regulate appetite and digestion. However, their mechanisms differ significantly.

Saxenda contains the active ingredient liraglutide, a GLP-1 receptor agonist. It works by activating a single satiety pathway in the brain, helping you feel fuller sooner and reducing hunger. Saxenda is designed to support weight loss primarily through appetite regulation and slowing gastric emptying. It was developed by Novo Nordisk and has been FDA-approved for chronic weight management since 2014.

Mounjaro contains tirzepatide, a dual glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 receptor agonist. This dual-action mechanism allows Mounjaro to target multiple pathways related to appetite control and metabolism simultaneously, hitting both brain satiety centres and fat cells. Mounjaro is also approved for use in adults with type 2 diabetes to help control blood sugar levels. It was FDA-approved for type 2 diabetes in May 2022 and subsequently approved for weight management as Zepbound in November 2023.

Receptor Action Comparison

Weight Loss Results – Mounjaro 2.6x Superior

Clinical trials paint a clear picture: Mounjaro delivers significantly more weight loss than Saxenda. The SURMOUNT-1 trial (Mounjaro) and the SCALE Obesity and Prediabetes trial (Saxenda) are the landmark studies for each medication.

In the SURMOUNT-1 trial, participants taking the highest dose of Mounjaro (15 mg) lost an average of 22.5% of their total body weight over 72 weeks, with 57% of participants achieving 20% or greater weight reduction. By comparison, in the SCALE trial, Saxenda participants lost an average of 8% of their body weight over 56 weeks, with approximately 33% losing more than 10%.

These weight loss results vary among individuals, but the overall trend is consistent: Mounjaro has been shown to result in about 15% more weight loss than Saxenda. When combined with a reduced-calorie diet and increased physical activity, both medications deliver clinically significant weight loss but Mounjaro produces results that approach those of bariatric surgery.

Clinical Trial Outcomes Comparison

Sources: SURMOUNT-1 (NEJM 2022); SCALE Obesity and Prediabetes (NEJM 2015)

Dosing + Administration Comparison

Saxenda requires a daily injection, totalling 365 injections per year. Mounjaro requires a once-weekly injection, totalling just 52 weekly injections per year eliminating 313 annual injections.

Both medications are self-administered via subcutaneous injection in the abdomen, upper arm, or thigh. Saxenda uses a multi-dose pen, while Mounjaro uses a single-dose auto-injector pen.

Saxenda dosing: The starting dose is 0.6 mg daily, increased by 0.6 mg at weekly intervals over approximately 17 days until the maintenance dose of 3.0 mg daily (the maximum dose) is reached. If a patient cannot tolerate a dose increases, the escalation may be delayed.

Mounjaro dosing: The starting dose is 2.5 mg weekly for four weeks, then gradually increased every four weeks. The titration period is approximately 20 weeks to reach the highest dose of 15 mg weekly. This slower titration helps prevent the nausea and stomach pain that lead to high discontinuation rates with faster escalation.

Patient Burden Comparison

Side Effects Profile Comparison

Common side effects of both Mounjaro and Saxenda include nausea, diarrhea, vomiting, constipation, abdominal pain, headache and decreased appetite. These digestive issues are common to all GLP-1 receptor agonists because of their mechanism of action slowing gastric emptying and reducing hunger signals.

The critical difference is tolerability. A higher percentage of people stop taking Saxenda due to side effects (approximately 27% in clinical trials) compared to Mounjaro (approximately 4-7% depending on dose). Mounjaro’s gradual titration over 20 weeks appears to significantly reduce the severity and duration of gastrointestinal side effects, improving long-term adherence.

Serious side effects for both medications include pancreatitis and gallbladder issues. Both medications are not recommended for individuals with a personal or family history of medullary thyroid cancer or multiple endocrine neoplasia type 2 (MEN 2). Additionally, Saxenda may cause mood changes, including depression or suicidal thoughts in some users a risk that should be discussed with your healthcare provider, particularly for patients with a history of mental health conditions.

Both medications carry a boxed warning about thyroid cancer risk based on animal studies. Patients should report any symptoms such as a lump in the neck, difficulty swallowing, or persistent hoarseness. Other medications you are taking and kidney problems should also be discussed with your provider, as both drugs can cause severe allergic reactions in rare cases.

To manage symptoms and reduce side effects, healthcare providers commonly recommend eating smaller meals, avoiding fatty or greasy foods, and staying hydrated. Most common side effects tend to resolve within the first several weeks of treatment as the body adjusts.

GI Tolerability Comparison

Sources: Saxenda prescribing information; Mounjaro prescribing information; SURMOUNT-1 (NEJM 2022); SCALE (NEJM 2015)

Cost Analysis 2026

Cost is a significant factor when comparing Saxenda and Mounjaro. Without insurance, Saxenda’s average monthly cost is approximately $1,349, while Mounjaro typically costs between $950 and $1,100 per month depending on the pharmacy. Saxenda generally costs more than Mounjaro at full retail price.

Insurance coverage varies significantly. Mounjaro is more likely to be covered by insurance when prescribed for type 2 diabetes, while coverage for weight loss use may be denied for both medications. Some insurance plans may help cover part of the cost, but prior authorization is often needed. To determine actual costs, it is advisable to call your insurance provider to find out what your plan covers.

If your insurance covers Mounjaro, you might pay as little as $25 for a one- to three-month supply using the manufacturer’s savings card. Savings cards and coupons can potentially save you hundreds of dollars if your pharmacy accepts them.

Monthly Pricing Comparison (2026)

Switching Saxenda → Mounjaro Protocol

Many patients considering switching from Saxenda to Mounjaro want to know the safest way to transition. Because both medications work in the same way as GLP-1 receptor agonists they should not be taken together due to their similar mechanisms of action.

The good news is that no washout period is typically required. Liraglutide (Saxenda’s active ingredient) has a half-life of approximately 13 hours, meaning it clears the body relatively quickly. Most patients can begin Mounjaro the day after their last Saxenda dose. However, some temporary overlap of GLP-1 effects in the first week is expected, which may cause mild gastrointestinal symptoms.

Your healthcare provider will determine the appropriate starting Mounjaro dose based on your current Saxenda dose and tolerability. Always follow your provider’s guidance rather than adjusting doses independently. An online consultation with a licensed prescriber can help determine the best switching protocol for your situation.

Conversion Guidelines

Important: These are general guidelines. Your healthcare provider should tailor the transition based on your complete medical history, current dose and how well you have tolerated taking Saxenda.