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ToolsCompareSemaglutide vs Thymalin

Semaglutide vs Thymalin

Side-by-side comparison of key properties, dosing, and research.

GLP-1 / Weight Loss Agonists
Semaglutide
Immune SupportAnti-Aging & Longevity
Thymalin
Summary
Semaglutide is an FDA-approved GLP-1 receptor agonist originally developed for type 2 diabetes that has proven remarkably effective for weight loss. Clinical trials show average 15–20% body weight reduction. It is marketed as Ozempic (diabetes) and Wegovy (weight management).
Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
Half-Life
~7 days
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
SubQ, Oral
SubQ, IM
Research
Typical Dose
0.25 mg → 0.5 mg → 1 mg → 1.7 mg → 2.4 mg
10 mg IM or SC daily
Frequency
Once weekly, subcutaneous
Once daily
Key Benefits
  • Average 15–20% body weight reduction in clinical trials (STEP trials)
  • Significant reduction in appetite and food cravings
  • Improvement in blood sugar control and insulin sensitivity
  • Reduces cardiovascular risk (SELECT trial: 20% reduction in MACE)
  • May reduce risk of kidney disease
  • Improves metabolic markers (cholesterol, blood pressure)
  • FDA-approved — extensively studied with robust safety data
  • Weekly dosing convenience
  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function
Side Effects
  • Nausea (most common, especially during titration)
  • Vomiting
  • Diarrhea or constipation
  • Abdominal discomfort
  • +4 more
  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)
Stacks With