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Safety & Sourcing

Should I get bloodwork before I start my first peptide?

Updated 2026-05-03

Yes, ideally. Baseline bloodwork is the single best safety move you can make before starting any peptide. It tells you if your liver, kidneys, blood sugar, or thyroid are already off, which changes how your body handles the drug. It also gives you a real before-and-after to track. For GLP-1s, focus on metabolic and pancreatic markers. For growth-hormone peptides, add IGF-1. For testosterone-related peptides, add a full hormone panel.

IfIf you are starting a GLP-1 like semaglutide or tirzepatide
Thenthen pull a CBC, CMP, lipid panel, HbA1c, and lipase before your first dose
IfIf you are starting a growth-hormone peptide like CJC-1295 or Ipamorelin
Thenthen add IGF-1 to your baseline so you can track response
IfIf you do not have a primary care doctor
Thenthen services like Marek Health, Inside Tracker, or Quest direct-to-consumer can pull a comprehensive panel without an in-person visit
IfIf your baseline shows abnormal liver enzymes or kidney function
Thenthen talk with a clinician before starting - peptides may be processed differently
Key facts
  • A starter panel usually includes CBC, CMP, lipid panel, HbA1c, and a baseline thyroid TSH
  • For GLP-1s, lipase is worth adding because pancreatitis is a listed boxed warning concern
  • For growth-hormone peptides, IGF-1 is the main efficacy and safety marker - higher levels are not always better
  • For TRT-adjacent peptides, pull total and free testosterone, estradiol, SHBG, hematocrit, and PSA
  • Fast 8 to 12 hours before bloodwork for accurate metabolic and lipid numbers
  • Repeat at the 3-month mark to confirm dose response and catch any drift early
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