IGF-1 LR3: research

IGF-1 LR3 dosage

Typical reported dose: 20–40 mcg once a day

• Reported 20–40 mcg daily: 20–40 mcg once daily once daily, under the skin. Reported by users, common report. Studied in: Adults discussing physique use. (source)
• Reported 50 mcg with breaks: 50 mcg per injection; the commenter did not state frequency not stated in this comment, under the skin. Reported by users, occasional report. Studied in: An adult forum commenter reporting SC use. (source)
• Reported 100 mcg into muscle: 100 mcg once daily once daily, into muscle. Reported by users, rare report. Studied in: An adult commenter reporting actual use. (source)
• Forum guide with longer cycles: 30–80 mcg daily, or a separate 50–120 mcg daily range once daily, under the skin. Reported by users, occasional report. Studied in: A community guide, not a clinical study. (source)
• One reported 20→40→60 mcg cycle: 20 mcg in week 1; 40 mcg in middle weeks; 60 mcg in the final week of a 5–6-week cycle before workouts; dosing frequency not stated, under the skin. Reported by users, rare report. Studied in: One 23-year-old man reporting SC pre-workout use. (source)

These are doses reported in labels, trials or user reports, not a personal plan. Check the source behind each one.

Work out syringe units with the dosing calculator

IGF-1 LR3 side effects and risks

Reported side effects

• Low blood sugar: LR3 rate unknown. Related mecasermin can cause severe low blood sugar., serious. Sweating, shaking, confusion or fainting need prompt blood sugar assessment. (source)
• Unwanted tissue or organ growth: Organ growth occurred in guinea pigs; human incidence is unknown., serious (source)
• Fluid retention, tingling or joint pain: Possible class effects; no LR3 specific human rate is available., moderate (source)
• Injection-site reactions or infection: No LR3 incidence estimate. Unregulated injectable quality adds risk., serious (source)
• Cancer-related concerns: A growth signalling concern, not a measured LR3 cancer rate., serious (source)

Stop and get help if

• Confusion, fainting, seizure or low blood sugar that persists: Stop exposure and get emergency care. Do not give food or drink to someone unconscious.
• Trouble breathing, facial swelling or widespread hives: Stop exposure and get emergency care.
• Severe headache with vomiting or new vision changes: Stop exposure and seek urgent care. Mecasermin, a related drug, can raise pressure around the brain.
• Chest pain, severe breathlessness or collapse: Get emergency care now.
• Fever with spreading redness, severe pain or swelling at an injection site: Seek urgent care for possible infection.

Who should avoid it

• pregnant: No human reproductive safety data.
• breastfeeding: Transfer into milk and infant effects are unknown.
• tryingToConceive: Reproductive safety is unknown. This is a precaution.
• under18: No human LR3 pediatric dose has been studied.
• activeCancer: Block active or suspected cancer because LR3 activates growth signalling.
• cancerHistory: Past cancer or a cancer-predisposing condition needs specialist review before growth-factor exposure.
• diabetes: LR3 may lower blood sugar. Human use in diabetes is unstudied.
• diabeticRetinopathy: Human IGF-1 research found worse diabetic eye disease. LR3 risk is unknown.
• seizureDisorder: Low blood sugar can trigger seizures. LR3 risk is unknown.
• sleepApnea: Related mecasermin can enlarge tonsils and obstruct breathing; LR3 risk is unknown.
• heartCondition: Swelling and heart effects need review. LR3 heart safety is unknown.
• kidneyDisease: No human LR3 clearance or dose-adjustment data.
• liverDisease: No human LR3 clearance or dose-adjustment data.
• surgeryPlanned: Fasting or blood sugar medicines need review for low blood sugar.
• other: Severe IGF-1 or ingredient allergy blocks re-exposure, as with related mecasermin.
• testedAthlete: WADA prohibits IGF-1 analogues at all times under S2.3.

Interactions

• Insulin: Expected additive low-blood-sugar risk. No LR3 interaction trial exists.
• Sulfonylureas and other insulin releasers: These medicines lower blood sugar; adding LR3 could compound that effect.
• Other IGF-1 products: LR3 combination safety is unknown.
• Growth hormone and GH secretagogues: People stack these to increase GH/IGF signalling. LR3 combination safety has not been studied.

Product quality risks

• A tested black-market vial contained LR3 with an extra His6 purification tag, not the expected finished molecule.
• A doping-laboratory report also identified unpurified LR3. Neither paper estimates today's market-wide failure rate.
• FDA found poor sterile-production practices at a facility that compounded LR3 among other unapproved products.

How IGF-1 LR3 works

LR3 activates the IGF-1 receptor, a signal for cells to grow and use nutrients. Its changes reduce binding to proteins that normally control IGF-1. That changes its activity in laboratory models. The size and duration of its effects in people are unknown.

• IGF-1 receptor: Activates growth and survival signals in cells.
• IGF-binding proteins: Binds less strongly than native IGF-1; activity cannot be converted dose-for-dose.

Half-life: Unknown in humans. The often-repeated 20–30-hour value is not confirmed by a human LR3 PK study.