What are the side effects of IGF-1 LR3?
The most commonly reported IGF-1 LR3 side effects are hypoglycemia (low blood sugar), eat carbs near dose, localized growth at injection site, theoretical: visceral organ growth at chronic high doses. Most are mild and tend to be dose dependent. It is generally avoided with active malignancy (real concern with IGF-1). Human clinical evidence for IGF-1 LR3 is limited, so this reflects reported and observed effects, not a complete safety profile.
Reported IGF-1 LR3 side effects
- Hypoglycemia (low blood sugar), eat carbs near dose
- Localized growth at injection site
- Theoretical: visceral organ growth at chronic high doses
- Headache
Who should avoid it
- Active malignancy (real concern with IGF-1)
- Diabetic retinopathy
- Pregnancy / nursing
- Hypoglycemia-prone
Bloodwork worth tracking
- Fasting glucose every 2 weeks
- IGF-1 baseline + at week 4
References
- IGF-I and its analogs in clinical use — Clemmons DR, Endocrinol Metab Clin North Am, 2012
- Detection of His-tagged Long-R3-IGF-I in a black market product — Kohler M, Thomas A, Walpurgis K, et al., Growth Hormone & IGF Research, 2010
- Site-specific fluorescent derivatization and liquid chromatographic-mass spectrometric characterization of long R(3) IGF-I for bioanalytical applications — Harvey MD, Banks PR, Journal of Chromatography B, 2003
Pepdex is an editorial reference, not medical advice. Peptides vary in legal and approval status by country, many are research compounds without full human safety data. Talk to a qualified clinician before starting anything.
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Last updated 2026-06-06.