What Is IGF-1 LR3?

IGF-1 LR3 is an engineered version of insulin-like growth factor 1 — the anabolic hormone GH stimulates the liver to produce. Two modifications (an arginine substitution and a 13-amino-acid extension) prevent binding proteins from capturing it, extending its active half-life from minutes to about a day.

That makes it the most direct anabolic molecule on this site: instead of asking the pituitary for GH and waiting for downstream IGF-1, it *is* the downstream signal — driving nutrient uptake, protein synthesis and cell growth wherever it binds. Power and risk scale together.

What is IGF-1 LR3 studied for?

Side effects & safety

Hypoglycemia is the acute one — IGF-1 has real insulin-like glucose effects, and injecting fasted at high doses can drop blood sugar dangerously. Chronic concerns: IGF-1's growth signal is precisely what makes cancer history an absolute contraindication.

Legal & approval status

Research chemical; no approvals. WADA-banned, and one of the compounds testing actually catches.

Typical dosing at a glance

Commonly reported protocols use 20 mcg–50 mcg, daily, often post-training, via subcutaneous injection. For the mixing math — how much bacteriostatic water, exact syringe units, doses per vial — see the IGF-1 LR3 reconstitution calculator →

Related peptides

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Educational overview based on published research and commonly reported community protocols — not medical advice, and not an endorsement of any compound. Consult a licensed healthcare provider.