IGF-1 LR3 (Long R3 IGF-1)
Long [Arg3] Insulin-like Growth Factor-1 (Long R3 IGF-1)
No human clinical trials have been conducted. All evidence comes from animal or laboratory studies.
A modified version of IGF-1 (a natural growth-promoting hormone) engineered to stay active in the body longer than the natural form. All published evidence comes from animal and laboratory studies showing tissue growth effects; no human clinical data exists for this specific version.
This entry is a cited research summary, not an established treatment reference. Dosing language is included as source context, not as medical instruction.
IGF-1 LR3 (Long R3 IGF-1) is preclinical or hypothesis-only.
No human clinical trials have been conducted. All evidence comes from animal or laboratory studies.
Safety Summary
Controlled human safety data for IGF-1 LR3 are absent. In fetal sheep, LR3-IGF-1 lowered plasma insulin and glucose after 1 week and reduced in vivo glucose-stimulated insulin secretion; acute infusion also suppressed insulin during a hyperglycemic clamp (PMID 33938236, PMID 37114757). In growth-restricted fetal sheep, circulating amino acids fell during treatment without a growth benefit PMID 39679943. By contrast, local controlled release in a rat sciatic-nerve conduit study did not produce systemic toxicity PMID 41015370. Community sources consistently report hypoglycemia as the primary practical concern, with users maintaining carbohydrate intake during use. The AACE/ACE guidelines for GH deficiency note that IGF-1 levels should be kept within age-related physiological range to minimize side effects PMID 31760824. All frequency and severity ratings above are extrapolated and community reports; no controlled human safety data exists for LR3.
Clinical check-in
If real-world use or exposure is being considered, review potential interactions, contraindications, and monitoring needs with a licensed clinician rather than relying on summary copy alone.
Cited sources
Every claim on this page links to one of the 16 sources below. Identifiers are PubMed (PMID), ClinicalTrials.gov (NCT), or DOI; click through to the source of record before acting on a claim.
- 1PMID 12947030PubMed
- 2PMID 33427051PubMed
- 3PMID 32573852PubMed
- 4PMID 33938236PubMed
- 5PMID 37114757PubMed
- 6PMID 39679943PubMed
- 7PMID 36091374PubMed
- 8PMID 39610283PubMed
- 9PMID 41015370PubMed
- 10PMID 33557137PubMed
- 11PMID 11566722PubMed
- 12PMID 22227200PubMed
- 13PMID 29626053PubMed
- 14PMID 21147149PubMed
- 15PMID 16739959PubMed
- 16PMID 37261455PubMed