Hemoglobin A1c (HbA1c)
%MetabolicBaselineQuarterly
Primary glycemic endpoint for GLP-1 RAs and tirzepatide in T2D; reassess at 3 months after dose escalation.
Backed by graded claim
Monitoring
Labs & Biomarkers
Which labs to order, when, and why — across every peptide class in the course. Each entry links back to the graded claim that justifies it, so you always know whether you're ordering a test for an A-grade indication or a D-grade hypothesis.
19 of 19 labs
Fasting plasma glucose (FPG)
mg/dLMetabolicBaselineDuring titration
Tracks fasting glycemic response between A1c checks; useful early during titration.
Lipid panel
mg/dLCardiacBaselineAnnual
GLP-1 RAs lower triglycerides modestly; SELECT showed MACE benefit independent of LDL.
Lipase
U/LSafety / monitoringAs needed
GLP-1 RA pancreatitis signal: order if epigastric pain. Routine surveillance not recommended.
Discontinue if lipase >3× ULN with abdominal pain or imaging evidence of pancreatitis.
Calcitonin
pg/mLEndocrineAs needed
Boxed warning for GLP-1 RAs and tirzepatide: contraindicated in personal/family hx of MTC or MEN-2.
Do not use as routine screening; rely on history. Order only if MTC suspected.
eGFR / creatinine
mL/min/1.73m²Renal / hepaticBaselineQuarterly
FLOW trial: semaglutide slows CKD progression. Monitor for AKI in volume-depleted patients with severe GI side effects.
Backed by graded claim
ALT / AST
U/LRenal / hepaticBaselineAnnual
Baseline hepatic function; useful for MASH-track patients and to rule out hepatotoxicity if symptomatic.
DEXA body composition
kg lean / fatBody compositionBaselineAnnual
Quantifies lean mass loss during rapid weight loss with GLP-1 RAs / multi-agonists; informs resistance-training prescription.
IGF-1
ng/mLEndocrineBaselineDuring titrationQuarterly
Surrogate for cumulative GH exposure. Target mid-normal for age; supraphysiologic levels raise insulin-resistance and neoplasia concern.
Stop or reduce dose if IGF-1 above age-adjusted upper limit.
Backed by graded claim
Fasting insulin
µIU/mLMetabolicBaselineQuarterly
GH and ghrelin-mimetic peptides can blunt insulin sensitivity. Monitor with HOMA-IR if titrating.
Morning cortisol
µg/dLEndocrineAs needed
Some ghrelin mimetics (e.g., older GHRPs) raised cortisol/prolactin; ipamorelin is selective. Confirm if symptomatic.
Prolactin
ng/mLEndocrineAs needed
Older GHRPs (GHRP-2/6) raised prolactin; check if galactorrhea, amenorrhea, or libido changes.
LH / FSH
mIU/mLEndocrineBaselineDuring titration
Confirm pituitary suppression on GnRH agonists; rule out flare during initiation.
Total testosterone / estradiol
EndocrineBaselineQuarterly
Confirm castrate-level T or E2 suppression on chronic GnRH analog therapy.
PSA
ng/mLSafety / monitoringBaselineQuarterly
Prostate cancer monitoring during GnRH therapy.
Full-body skin exam
Safety / monitoringBaselineAnnual
Melanotan-II and afamelanotide pigmentation effects: document moles at baseline; refer changes promptly.
Document any new or changing nevi; biopsy threshold should be low in melanotan-II users.
Backed by graded claim
Serum sodium
mEq/LSafety / monitoringBaselineDuring titration
Desmopressin → hyponatremia risk, especially in elderly or those with high free-water intake.
Stop desmopressin and restrict fluids if Na < 130; check 3 days after each dose change.
CBC with differential
Safety / monitoringBaselineAnnual
Baseline before any chronic peptide therapy; useful to detect injection-site infection or contamination-related cytopenias from grey-market product.
Product endotoxin / sterility (chain-of-custody)
Safety / monitoringAs needed
For compounded peptides, request CoA showing identity, purity, and endotoxin testing before dispensing.
Backed by graded claim