MounjarovsSaxenda

Mounjaro's active ingredient, tirzepatide, is a "dual agonist" that activates two gut-hormone receptors at once: GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1). Most older drugs in this class hit only GLP-1. By stimulating both, tirzepatide prompts the pancreas to release insulin when blood sugar is high, lowers the glucagon hormone that raises blood sugar, slows how fast the stomach empties, and reduces appetite. The net effect is better blood-sugar control and, as a downstream benefit, significant weight loss. A built-in fatty-acid chain lets it bind to blood albumin, giving it a long half-life so it only needs to be injected once a week.

Saxenda's active ingredient is liraglutide, a GLP-1 receptor agonist that mimics glucagon-like peptide-1, a natural gut hormone released after eating. By activating GLP-1 receptors in the brain's appetite centers, it increases feelings of fullness and reduces hunger, which tends to lower how many calories you eat. It also slows stomach emptying, so food stays in the stomach longer. Because liraglutide is relatively short-acting, it must be injected once every day, unlike newer once-weekly GLP-1 drugs.

In SURPASS-2, an open-label 40-week head-to-head trial of 1,879 adults with type 2 diabetes published in the New England Journal of Medicine (2021), tirzepatide beat injectable semaglutide 1 mg. In the primary (treatment-regimen) analysis, the 15 mg dose lowered A1C by about 2.30 percentage points and reduced body weight by roughly 11.2 kg (about 12% from a baseline near 94 kg), and the 5 mg dose lowered A1C by about 2.01 points with about 7.6 kg lost — versus 1.86 points and 5.7 kg with semaglutide. (In the secondary on-treatment analysis, 15 mg figures were larger, about 2.46 points and 12.4 kg.) About 60% of participants on 15 mg hit a combined target of A1C 6.5% or lower plus at least 10% weight loss, compared with 22% on semaglutide. In the separate SURPASS-CVOT outcomes trial (about 13,300 patients with type 2 diabetes and established atherosclerotic heart disease, ~4-year median follow-up, published in NEJM in 2025), tirzepatide was non-inferior to dulaglutide for major adverse cardiovascular events (HR 0.92) and showed a 16% lower rate of all-cause death (HR 0.84), alongside greater A1C and weight reductions. These trials were in people with type 2 diabetes; your results may differ.

In the pivotal SCALE Obesity and Prediabetes trial (NEJM, 2015), adults without diabetes lost a mean of 8.0% of body weight on liraglutide 3.0 mg versus 2.6% on placebo at 56 weeks. About 63% of liraglutide patients lost at least 5% of body weight (vs. 27% on placebo) and roughly 33% lost at least 10% (vs. 11% on placebo). However, in the head-to-head STEP 8 trial (JAMA, 2022), once-weekly semaglutide 2.4 mg produced 15.8% mean weight loss versus 6.4% for daily liraglutide 3.0 mg over 68 weeks, more than double the effect. Individual results vary and depend heavily on combining the drug with diet and activity.

The most common side effects are gastrointestinal: nausea, diarrhea, decreased appetite, vomiting, constipation, indigestion, and abdominal pain. These are usually mild to moderate, most pronounced when starting and after each dose increase, and tend to ease over days to weeks. Serious but less common risks include acute pancreatitis (severe, persistent stomach pain — seek care immediately), gallbladder problems and gallstones (more likely during rapid weight loss), severe low blood sugar especially when combined with insulin or sulfonylureas, kidney injury from dehydration due to vomiting or diarrhea, allergic reactions, and possible worsening of diabetic retinopathy. The boxed warning concerns thyroid C-cell tumors seen in rodents; whether this risk applies to humans is unknown, so watch for a neck lump, hoarseness, trouble swallowing, or persistent shortness of breath and tell your doctor. Report any severe or persistent symptoms to your prescriber.

The most common side effects are gastrointestinal: nausea, vomiting, diarrhea, constipation, and abdominal pain, typically mild-to-moderate and worst during the first weeks as the dose is increased. Headache, low blood sugar (especially in people with type 2 diabetes), increased heart rate, and injection-site reactions also occur. Serious but uncommon risks include acute pancreatitis, gallbladder disease (gallstones), and kidney problems from dehydration. Saxenda carries an FDA boxed warning for thyroid C-cell tumors based on rodent studies; whether this risk applies to humans is not known. Seek urgent medical care for severe, persistent abdominal pain, signs of an allergic reaction, or a lump or swelling in the neck.

As of September 2026, LillyDirect lists Mounjaro's self-pay price as starting at $499/month for a one-month supply at every strength from 2.5 mg to 15 mg. Without that program, pharmacy cash prices run roughly $1,000 or more per month. With commercial insurance that covers Mounjaro for type 2 diabetes, Lilly's savings card can lower the copay for eligible patients (caps apply; not available with Medicare, Medicaid, TRICARE or VA coverage). Medicare Part D may cover Mounjaro for type 2 diabetes but not for weight loss. Confirm pricing and coverage before starting.

As of 2026, Saxenda's cash price without insurance runs roughly $1,300 to $1,650 per month for a 30-day supply (five prefilled pens), varying by pharmacy. Pharmacy discount coupons (e.g., GoodRx) can cut this to around $370-$500. Insurance coverage is inconsistent, often requires prior authorization, and many commercial plans, plus Medicare, exclude weight-loss drugs entirely. Note that Novo Nordisk's $25 Saxenda Savings Card was discontinued for new enrollees in mid-2023, so it is no longer a reliable way to lower cost; uninsured patients with limited income may instead qualify for free medication through the Novo Nordisk Patient Assistance Program. A lower-cost generic liraglutide (from Teva) launched in the US in 2025 at roughly $1,165 per month, which may reduce out-of-pocket costs over time as availability expands.

Mounjaro is FDA-approved as an add-on to diet and exercise to improve blood sugar control in adults and pediatric patients 10 years and older with type 2 diabetes. It is NOT FDA-approved for weight loss or for type 1 diabetes. It should NOT be used by anyone with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) — this is a boxed warning. Avoid or use with caution if you have a history of pancreatitis, severe gastrointestinal disease such as gastroparesis, diabetic retinopathy, or known hypersensitivity to tirzepatide. It is not recommended in pregnancy. Because delayed stomach emptying can reduce absorption of oral pills, Lilly advises people using oral hormonal contraceptives to switch to a non-oral method or add a barrier method for four weeks after starting and for four weeks after each dose increase. Discuss kidney issues and any history of gallbladder disease with your prescriber.

Saxenda is FDA-approved for adults with obesity (BMI 30 or higher) or with a BMI of 27 or higher plus at least one weight-related condition such as high blood pressure, type 2 diabetes, or high cholesterol, and for adolescents aged 12-17 who weigh more than 132 lbs (60 kg) and have obesity. It is meant to be used alongside a reduced-calorie diet and increased physical activity. It is contraindicated in anyone with a personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN 2), in pregnancy, and in people with a prior serious allergic reaction to liraglutide. It should not be combined with other GLP-1 medicines and is used cautiously in those with a history of pancreatitis or gallbladder disease. Your prescriber makes the final eligibility decision.