Editorial review: Medriva pages are written by named contributors, reviewed by clinical or subject-matter experts, and updated as evidence or regulatory status changes.

IGF-1 LR3: Evidence, Side Effects, and Regulatory Status (2026)

Q: Is IGF 1 LR3 FDA approved?

Not FDA approved. See the regulatory status section above for details.

Q: Does IGF 1 LR3 work for muscle growth?

Evidence is anecdotal . See the linked use case hub for the full breakdown.

Q: How much does IGF 1 LR3 cost?

See the cost pages or the GLP 1 price/supply tracker where applicable.

IGF-1 LR3 is Not FDA-approved. Evidence grade: anecdotal. This page is clinically reviewed.

TL;DR / Quick Facts

IGF-1 LR3 is IGF-1 LR3 is a long-acting recombinant IGF-1 analog. Studied in cell culture and rodent muscle models. Not FDA-approved; sold as RUO. FDA status: Not FDA-approved. Typical use cases: muscle growth, bodybuilding. Evidence grade: anecdotal. Dosing is not established (no FDA-approved protocol). Common side effects: see below. Medriva editorial stance: this compound has limited human evidence; consult a licensed clinician.

What it is

IGF-1 LR3 is a member of the Long-acting IGF-1 analog class. IGF-1 LR3 binds IGF-1R, activating PI3K/Akt/mTOR. Potent anabolic signal but also proliferation signal; long-term safety profile is not established.

What the evidence says

Evidence for IGF-1 LR3 is anecdotal. The bulk of the evidence is from pre-clinical models and small or uncontrolled human studies. Well-controlled phase 3 trials are limited or absent.

[Detailed evidence breakdown in the corresponding claim or pillar pages is linked at the bottom of this page.]

What it's used for

Commonly discussed uses of IGF-1 LR3:

Muscle Growth — anecdotal evidence.
Additional uses listed in the linked use-case hubs; evidence varies by indication.

For the full list, see the linked use-case hubs below.

Dosing is unestablished

No FDA-approved dosing protocol exists for Igf 1 Lr3. Published research and clinic-marketed protocols are not interchangeable with medical guidance. Medriva does not publish dosing instructions for research-use or non-approved compounds. Review quality controls with a licensed clinician and use the vendor evaluation framework and COA explainer before considering any source.

Side effects and risks

Common: Side effects vary by compound and indication; review the approved label or profile-specific safety data with a clinician.
Serious: Seek urgent care for severe allergic symptoms, chest pain, severe abdominal pain, persistent vomiting, or other severe reactions.
Long-term unknowns: For non-approved or research-use compounds, long-term human safety data may be limited.

Regulatory status

FDA-approved use(s): None. RUO.
Compounded availability: see 503A vs 503B explainer
Research-use-only (RUO) availability: yes
Banned in sport: see WADA & sports explainer

Cost and access

IGF-1 LR3 is available primarily via telehealth platforms and 503A compounding pharmacies. For pricing, see our cost pages or the GLP-1 price/supply tracker where applicable.

Who it might be appropriate for

Adults with a relevant diagnosed condition or clinical goal, under the supervision of a licensed clinician, who have no contraindications. IGF-1 LR3 is not for self-experimentation.

Who should not use it

Contraindications vary by compound, indication, pregnancy status, comorbidities, and current medications. For the full list, see the contraindications checklist and discuss with your clinician.

Medriva editorial stance

We describe the literature. We do not promote IGF-1 LR3 as a cure, treatment, or performance enhancer. We do not recommend it for self-experimentation. We do recommend that readers (a) understand the evidence grade (anecdotal), (b) understand the regulatory status (Not FDA-approved), and (c) discuss with a licensed clinician before acting.

How to talk to a clinician

See our guide on how to talk to a clinician for a templated conversation.

Frequently Asked Questions

Is IGF-1 LR3 FDA-approved?

Not FDA-approved. See the regulatory status section above for details.

Does IGF-1 LR3 work for muscle growth?

Evidence is anecdotal. See the linked use-case hub for the full breakdown.

What are the side effects?

See the side effects section above. Discuss with your clinician.

How much does IGF-1 LR3 cost?

See the cost pages or the GLP-1 price/supply tracker where applicable.

Can I buy IGF-1 LR3 online?

Only via prescription from a 503A compounding pharmacy or a licensed telehealth platform. Medriva does not sell peptides and does not endorse RUO vendors.

Author + Clinical reviewer

Author: Priya Menon, MS Clinical reviewer: Jonathan Reeves, MD Last reviewed: 2026-06-05

Next steps

Review the evidence grade and regulatory status before making decisions about Igf 1 Lr3.
Bring this page to a licensed clinician if you are discussing benefits, risks, or alternatives.
Subscribe to the Medriva Peptide Brief for evidence and regulatory updates.

Related use-case hubs

Related comparisons

Igf 1 Lr3 Vs Hgh

Editorial process

This page follows the Medriva Editorial Policy and the Clinical Review Methodology. Page last reviewed: 2026-06-05. Author: Priya Menon, MS. Clinical reviewer: Jonathan Reeves, MD.

Current source updates

For new regulator actions, compounding-policy changes, warning letters, shortage updates, and sports-rule changes, review the Peptide Tracker before relying on older summaries.