Peptide Comparison
TirzepatidevsSemaglutide
The dual-action powerhouse that targets both GIP and GLP-1 receptors, delivering the most dramatic weight loss results ever seen in a medication—averaging over 20% body weight reduction while also crushing blood sugar levels in people with diabetes.
The revolutionary once-weekly GLP-1 medication that helps your body feel full faster and longer, leading to significant weight loss while also protecting your heart—FDA approved and backed by some of the largest clinical trials in obesity medicine history.
At a Glance
Quick
comparison
Dose Range
Tirzepatide
2.5–15 mg
Semaglutide
0.25–2.4 mg
Frequency
Tirzepatide
Once weekly
Semaglutide
Once weekly
Administration
Tirzepatide
Subcutaneous injection
Semaglutide
Subcutaneous injection
Cycle Length
Tirzepatide
Ongoing/indefinite
Semaglutide
Ongoing/indefinite
Onset Speed
Tirzepatide
Moderate (1-2 weeks)
Semaglutide
Moderate (1-2 weeks)
Evidence Level
Tirzepatide
Strong human trials (Phase 3 or FDA approved)
Semaglutide
Strong human trials (Phase 3 or FDA approved)
Efficacy
Benefit
ratings
Weight Loss
Appetite Control
Blood Sugar Control
Heart Protection
Technical Data
Compound
specifications
Tirzepatide
Molecular Formula
C225H348N48O68
Molecular Weight
4813.45 g/mol
Half-Life
Approximately 5 days (120 hours)
Bioavailability
~80% (subcutaneous)
CAS Number
2023788-19-2
Semaglutide
Molecular Formula
C187H291N45O59
Molecular Weight
4113.58 g/mol
Half-Life
Approximately 7 days (168 hours)
Bioavailability
89% (subcutaneous); 0.4-1% (oral, with absorption enhancer)
CAS Number
910463-68-2
Protocols
Dosing
tiers
Tirzepatide
Semaglutide
Applications
Best
suited for
Tirzepatide
People Who Want Maximum Weight Loss Results
If you're serious about losing significant weight, tirzepatide delivers results that were previously only achievable through bariatric surgery. Clinical trials showed average weight loss exceeding 20% of body weight—that's 50+ pounds for someone starting at 250 pounds. No other medication comes close.
Those Who Haven't Succeeded with Semaglutide
Thanks to its dual GIP/GLP-1 mechanism, tirzepatide often works better for people who had limited results with GLP-1-only drugs like semaglutide. The added GIP activation provides extra metabolic benefits that can break through plateaus and deliver superior weight loss.
People with Type 2 Diabetes Needing Aggressive Control
Head-to-head trials proved tirzepatide beats semaglutide for blood sugar control. The average HbA1c reduction of over 2 percentage points means many people can dramatically reduce or eliminate other diabetes medications. It's a genuine game-changer for metabolic health.
Individuals Looking to Transform Their Relationship with Food
Tirzepatide doesn't just reduce hunger—it fundamentally changes how food appeals to you. Users describe feeling free from constant food thoughts, finding it easy to stop eating when satisfied, and losing interest in formerly irresistible treats. It's not willpower—it's biochemistry working for you.
Semaglutide
People with Obesity Seeking Significant Weight Loss
If your BMI is 30 or higher (or 27+ with weight-related health conditions), semaglutide is currently one of the most effective non-surgical weight loss options available. Clinical trials show average weight loss of 15% of body weight—that's 30+ pounds for someone starting at 200 pounds.
Those Who've Struggled with Diet and Exercise Alone
Semaglutide works by changing the biological signals that drive hunger and cravings. If you've tried to lose weight through willpower alone and found yourself constantly battling hunger, this medication addresses that underlying biology rather than just telling you to eat less.
People with Type 2 Diabetes Needing Better Control
Originally developed for diabetes, semaglutide excellently controls blood sugar while also promoting weight loss—addressing two major health concerns simultaneously. It can often allow people to reduce or eliminate other diabetes medications.
Individuals at High Cardiovascular Risk
The SELECT trial proved that semaglutide reduces heart attacks, strokes, and cardiovascular death by 20% in people with obesity and existing heart disease—even without diabetes. It's one of the few weight loss medications proven to improve hard cardiovascular outcomes.
Safety Profile
Side
effects
Tirzepatide
Common
- Nausea
- Diarrhea
- Decreased Appetite
- Vomiting
Uncommon
- Gallbladder Problems
- Hair Thinning (Telogen Effluvium)
Serious
- Pancreatitis
- Thyroid Tumors (Theoretical Risk)
Semaglutide
Common
- Nausea
- Constipation or Diarrhea
- Decreased Appetite
- Vomiting
Uncommon
- Gallbladder Problems
- Hair Loss (Telogen Effluvium)
Serious
- Pancreatitis
- Thyroid Tumors (Theoretical Risk)
Research Status
Safety
& evidence
Tirzepatide
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for this use
Safety Overview
Tirzepatide has been extensively studied in the SURPASS (diabetes) and SURMOUNT (obesity) trial programs, involving thousands of participants over multiple years. The FDA approved it after thorough safety review. While GI side effects are common (especially during dose increases), they're typically mild to moderate and improve over time. Serious adverse events are rare. The SURPASS-CVOT trial is ongoing to evaluate long-term cardiovascular outcomes.
Contraindications
- xPersonal or family history of medullary thyroid carcinoma (MTC)
- xMultiple Endocrine Neoplasia syndrome type 2 (MEN2)
- xHistory of serious allergic reaction to tirzepatide or any GLP-1/GIP medication
- xCurrent or recent pancreatitis
- xPregnancy or planning to become pregnant
Semaglutide
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for this use
Safety Overview
Semaglutide has been studied in over 20,000 participants across multiple large clinical trials, making it one of the most thoroughly researched weight loss medications available. The FDA approved it after rigorous review of safety data. While GI side effects are common (especially early on), serious side effects are rare. The SELECT trial showed it actually reduces cardiovascular events, adding a safety benefit beyond just weight loss.
Contraindications
- xPersonal or family history of medullary thyroid carcinoma (MTC)
- xMultiple Endocrine Neoplasia syndrome type 2 (MEN2)
- xHistory of serious allergic reaction to semaglutide
- xCurrent or recent pancreatitis
- xPregnancy or planning to become pregnant
Decision Guide
Which is
right for you?
Choose Tirzepatide if...
- Maximum weight loss results
- Long-term obesity management
- Type 2 diabetes control
- Metabolic health improvement
Choose Semaglutide if...
- Significant weight loss
- Long-term weight management
- Cardiovascular risk reduction
- Blood sugar control