Medical Weight Loss Injections

Main Types of Medical Weight Loss Injections

1. GLP-1 Agonists

These medications mimic the body’s natural GLP-1 hormone, which increases feelings of fullness and decreases appetite.

• Semaglutide (brand names: Wegovy, Ozempic): A once-weekly injection approved for both type 2 diabetes and chronic weight management. Semaglutide is highly effective, with studies showing average weight loss of 15% or more of starting body weight over 12–16 months when combined with lifestyle changes.

• Liraglutide (brand name: Saxenda): A daily injection that also acts as an appetite suppressant. It is FDA-approved for weight loss in adults and teens and is proven to support ongoing weight reduction when diet and exercise alone aren’t sufficient.

• Tirzepatide (brand names: Zepbound, Mounjaro): A dual-action injection (GLP-1 and GIP receptor agonist) given weekly. Studies show even greater average weight loss—up to 21% of starting weight in some clinical trials, often recommended for those with obesity and/or diabetes.

2. Other Injection Types

• Fat-burning/metabolism-boosting shots: Typically vitamin B12 or lipotropic compounds. While sometimes marketed for weight loss, there is less scientific support for significant, lasting results compared to GLP-1/GIP medications.

• Experimental/new injectables: Medications like bimagrumab and Maritide are under clinical trial for future approval.

How They Work

These injections generally:

• Suppress appetite and increase feelings of satiety (fullness)

• Reduce preference for high-fat/high-calorie foods

• Slow gastric emptying, sustaining fullness after meals

• Lower blood sugar, which may be especially important for people with type 2 diabetes.

Who Qualifies?

• Adults (and sometimes teens) with a BMI ≥30, or BMI ≥27 with at least one weight-related health condition (e.g., hypertension, diabetes)

• After unsuccessful attempts with diet and exercise alone

• Cleared by a healthcare provider for safety—these cannot be bought over the counter and require ongoing medical monitoring.

Effectiveness

• Clinical studies show people lose on average 8%–21% of body weight within 12–18 months, depending on the medication and individual adherence.

• Success is best achieved when injections are combined with healthy diet, increased physical activity, and behavioral support.

• If the medicine is stopped, weight regain is common—these are generally considered long-term therapies.

Side Effects & Risks

• Most common: Nausea, vomiting, diarrhea, constipation, and heartburn, especially as the body adjusts.

• Rare: Pancreatitis, gallbladder disease, and possible thyroid tumor risk (seen in animal studies).

• Not all insurance covers these drugs for weight loss—even if approved for diabetes. Monthly cost can range from $1,000–$1,300 without insurance, though some manufacturers now offer cash-pay discounts.

• Injections are not suitable for those who are pregnant, breastfeeding, or have a history of certain cancers or pancreatitis.

Summary

Medical weight loss injections—primarily semaglutide, tirzepatide, and liraglutide—offer substantial, safe, and clinically proven weight loss for eligible patients under medical care. They are not a quick fix and work best as part of a broader, medically supervised weight loss plan. Discuss eligibility, risks, and alternatives with your healthcare provider before starting any injection regimen.