▶ IGF-1 LR3 · SUBTOPIC · DOSING LITERATURE
IGF-1 LR3 Dosing Literature
For Laboratory Research Use Only. The content below describes dose ranges as reported in peer-reviewed publications. This page does not recommend any dose for human use. No clinical claim is made. Always consult the original source publication.
SCOPE OF THIS PAGE
This page documents the published-literature dose ranges that appear in trials and animal studies of IGF-1 LR3. Every dose mention is bound to a citation (author, year, PMID where available). The PEPPUDEX wiki phrases these as descriptive observations of the research record, not as instructions to the reader.
ROUTES OF ADMINISTRATION IN PUBLISHED RESEARCH
The published research record for IGF-1 LR3 reports the following route(s) of administration: Subcutaneous (research). Route selection in a study reflects pharmacokinetic considerations specific to that protocol and is not a recommendation for any human use of IGF-1 LR3.
PHARMACOKINETIC HALF-LIFE
Published pharmacokinetic data report a half-life for IGF-1 LR3 of approximately ~6 hours (vs ~10 minutes native IGF-1). Half-life is the kinetic parameter that frames the dosing rhythm chosen in trial design. It is a measurement, not a recommendation.
CITED DOSE RANGES IN THE LITERATURE
The peer-reviewed sources below report dose ranges, frequencies, and durations used in studies of IGF-1 LR3. Refer to the original publication for full protocol detail.
- Tomas FM, Knowles SE, Owens PC, et al. (1993) reports the IGF-1 LR3 protocol used in Long-R3-IGF-I increases protein synthesis in rat skeletal muscle, published in J Endocrinol. See the source for the protocol-level dose range, frequency, and duration. link
- Walton PE, Dunshea FR, Ballard FJ (1995) reports the IGF-1 LR3 protocol used in Pharmacokinetics of LR3-IGF-I in lambs, published in J Endocrinol. See the source for the protocol-level dose range, frequency, and duration. link
DOSING Q+A FROM LITERATURE
The questions below summarise dosing-relevant entries from the literature record. Each answer is descriptive of published material and is not a recommendation.
▶ What is IGF-1 LR3?
IGF-1 LR3 (Long R3 Insulin-like Growth Factor 1) is an 83-residue synthetic analog of native IGF-1 with an N-terminal 13-residue extension and an arginine substitution at position 3. The modifications reduce binding to IGF-binding-proteins (IGFBPs), extending plasma half-life dramatically.
▶ Why is IGF-1 LR3 half-life longer than native IGF-1?
Native IGF-1 is rapidly cleared due to high-affinity binding by IGFBP-3 and other IGFBPs. The Arg-substitution at position 3 in LR3 significantly reduces IGFBP binding, leaving more free IGF-1 available for receptor engagement. Half-life extends from ~10 minutes (native) to ~6 hours (LR3).
▶ Side effects of IGF-1 LR3?
Hypoglycemia is the most acute concern · at higher doses LR3 binds the insulin receptor with sufficient affinity to lower blood glucose. Theoretical concerns with chronic high-dose use include organ enlargement and exacerbation of active malignancy via IGF-1 axis growth signaling.
▶ How is IGF-1 LR3 stored?
Lyophilized at 2–8 °C for 12+ months. Reconstituted at 2–8 °C, use within 14 days. Protein peptides this large are more sensitive to repeated freeze-thaw than smaller peptides; aliquot-freeze for long storage.
▶ Why is IGF-1 LR3 sometimes confused with IGF-1 DES?
Both are modified IGF-1 analogs. LR3 has an N-terminal extension that reduces IGFBP binding (long half-life). DES has the opposite · a tripeptide deletion at the N-terminus that also reduces IGFBP binding but with different receptor-affinity profile and shorter half-life. They are distinct compounds.
STORAGE OF THE REFERENCE COMPOUND
Lyophilized · 2–8 °C, 12+ months
Reconstituted · 2–8 °C, 14 days
Storage conditions describe the stability of the research-grade reference material, not a dosing protocol.
RECONSTITUTION MATH (CALCULATOR)
The PEPPUDEX reconstitution calculator at /calculator returns volume-per-dose math given vial mg, BAC mL, and a target dose in mcg. The calculator performs arithmetic only. It does not recommend a dose. Any number entered by a researcher must come from their own protocol design or the cited literature.
REGULATORY CONTEXT
FDA · Not FDA-approved. Research-use only. Note: increlex (mecasermin) is FDA-approved recombinant native IGF-1 for severe primary IGF-1 deficiency · distinct molecule from LR3.
WADA · IGF-1 and analogs prohibited at all times under WADA Section S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics).
RELATED PAGES
▶ LAST UPDATED · 2026-05-19