Peptide Guide · Growth Hormone Support
IGF-1 LR3
A long-acting form of IGF-1, the hormone that carries out most of growth hormone’s effects on muscle.
FORMSInjectable, after exercise
TYPICAL COURSEUp to 4 weeks, then 4+ off
STATUSCompounded, Rx only
STATESWA ID MT UT AZ OH IL
The science
How it works
Acts directly
Binds IGF-1 receptors on muscle and other tissues.
Avoids binding proteins
Stays active far longer than natural IGF-1.
Drives growth signaling
Promotes muscle cell growth and repair.
Lowers blood sugar
Acts like insulin, which is the main risk.
Natural IGF-1 is well studied, and a natural-sequence version is FDA-approved for a rare deficiency. IGF-1 LR3 itself has no human clinical data.
Dosing
Your dosing plan
Dr. Wright sets your exact dose within this range at your visit.
Standard protocol
FormSubcutaneous
Dose20 mcg (10 units)
ScheduleAfter exercise, with food
Based onClinical convention
Ceiling
FormSubcutaneous
Dose40 mcg (20 units)
ScheduleMaximum
Based onClinical convention
Course
Form—
DoseUp to 4 weeks
ScheduleThen at least 4 off
Based onClinical practice
Side effects
Side effects and what to expect
Low blood sugar
Common · Hours after a dose
Always dose with food. Eat carbohydrates at the first sign.
Redness at the injection site
Common · First few weeks
Rotate sites.
Joint aches or swelling
Uncommon · Any time
Let us know.
Headache
Uncommon · After doses
Stay hydrated.
A note from Dr. Wright
IGF-1 LR3 bypasses the feedback that limits every other peptide in this category. I use it rarely, in short courses, and with blood sugar monitoring.
Dr. Jason Wright, D.O. · Board certified, American Board of Cosmetic Surgery
Cost & access
Getting started with IGF-1 LR3
IGF-1 LR3
1 mg in a 5 mL vial (200 mcg/mL) · Labeled in your name
1 mg liquid vial (200 mcg/mL, 5 mL)
$220
Questions
Common questions
How is this different from growth hormone peptides?
It acts directly on tissues rather than prompting growth hormone release.
Why with food?
It lowers blood sugar. Food prevents lows.
Is there human research?
Not for this specific form. Natural IGF-1 is well studied.
How long is a course?
Up to 4 weeks, then at least 4 off.
Research
Supporting studies
Natural-sequence IGF-1 (mecasermin) is FDA-approved for severe primary IGF-1 deficiency
Increlex prescribing information
