IGF-1 LR3 Dosage Chart and Calculator: The Common Protocol
IGF-1 LR3 dosage chart: units per dose by vial size for the 20-50 mcg common protocol, a calculator, and the animal doses actually published. No trial set a dose.
The short version
No controlled human trial has ever given IGF-1 LR3 to a person and measured a dose. The protocol most often used in practice is 20-50 mcg by subcutaneous injection once daily in the morning with food, for roughly 1.5-6 weeks followed by a 4-6 week break. This is common practice, not something a trial established. What is published is animal dosing: mini-pump infusion and single injections in rats, single injections in pigs, intranasal dosing in mice and intravenous infusion into fetal sheep. The methods and doses say nothing about a dose under the skin in a person.
- The protocol most commonly used is 20-50 mcg subcutaneously once daily, AM with food, cycled 1.5-6 weeks with a 4-6 week break. It is common practice, not trial-established.
- No human trial of IGF-1 LR3 exists at any dose. The numbers above come from circulating practice, not a study.
- Published animal dosing exists only in rats, pigs, mice and fetal sheep, mostly by mini-pump infusion, single injection or IV infusion. None is a human number.
- Mecasermin's label warns of severe hypoglycaemia, and in pigs IGF-1 LR3 itself lowered blood glucose more potently and for longer than native IGF-1. Neither is a measurement in people.
No human trial has ever established a dose for IGF-1 LR3. This page gives the protocol most often used in practice, labelled as common practice rather than trial-established. It also covers what has been studied (animal dosing in rats, pigs, mice and fetal sheep) and why none of it is a human number. Background on what IGF-1 LR3 is, how it differs from the approved drug mecasermin, and its legal status is on the main IGF-1 LR3 page.
US legal status - Research use only
Sold for laboratory research use only. Not approved by the FDA for human use, and cannot be lawfully marketed as a supplement or a medicine. Products sold this way are not made to pharmaceutical quality standards, and their contents are not verified by anyone.
IGF-1 LR3 dosage: the common protocol
The protocol most often used is 20-50 mcg by subcutaneous injection once daily, typically in the morning with food to offset the glucose-lowering effect. It runs for roughly 1.5 to 6 weeks, with a 4-6 week break before the next cycle.
No controlled human trial has given IGF-1 LR3 to a person and measured a dose, a frequency, or a duration. What is published is animal work, below.
Common protocol
What is commonly used, not a dose established in trials. No regulator has set a dose for IGF-1 LR3. Sources differ, so the ranges below span them.
- Dose per administration
- 20-50 mcg
- How often
- once daily
- Route
- Subcutaneous injection
- Cycle length
- 1.5-6 weeks
- Break between cycles
- 4-6 weeks
- Common vial size
- 1 mg
- Timing
- Morning, alongside food, to offset the glucose-lowering effect.
- Commonly paired with
- MK-677, BPC-157, CJC-1295, Ipamorelin
Common protocols start at 20 mcg for 2-3 days to assess tolerance before increasing. Sources disagree on cycle length, describing anywhere from a 10-day pulse to a full 4-6 week run before the same 4-6 week break. Source upgrade pass (2026-09-27): searched specifically for a compounding-pharmacy, telehealth-clinic or published human-trial source (Belmar, Tailor Made Compounding, Defy Medical, Marek Health, PeterMD, American Medical Wellness, TeleWellnessMD, and a general search for any IGF-1 LR3 trial). No stronger source turned up real numbers - every telehealth/clinic page either had no public dosing content or just restated the same 20-40 mcg/day figure without citing a study, and it remains true, as multiple pages independently state, that no formal human clinical trial has ever evaluated IGF-1 LR3 specifically (the approved IGF-1 product Increlex/mecasermin is a different, non-LR3 molecule and not a valid stand-in). Kept the record as is rather than forcing an upgrade; both existing sources were re-fetched this session and still state the same numbers.
Plan a cycle in the protocol builder or work out injection volume in the dosage calculator.
The common IGF-1 LR3 dose is 20-50 mcg, once daily. From a 1 mg vial mixed with 2 mL of bacteriostatic water, 35 mcg is 7 units (0.07 mL) on a U-100 insulin syringe.
IGF-1 LR3 1 mg vial: units per dose
Full 1 mg vial page: mixing, doses per vial, how long it lasts →
| Water added | Concentration | 1 unit = | 20 mcg | 35 mcg | 50 mcg |
|---|---|---|---|---|---|
| 1 mL | 1 mg/mL | 10 mcg | 2 units | 3.5 units | 5 units |
| 2 mL | 0.5 mg/mL | 5 mcg | 4 units | 7 units | 10 units |
| 3 mL | 0.33 mg/mL | 3.33 mcg | 6 units | 10.5 units | 15 units |
All IGF-1 LR3 vial sizes: 1 mg
Units are on a standard U-100 insulin syringe (100 units = 1 mL), rounded to the nearest half unit - half-unit marks are on 0.3 mL syringes. Water volumes are examples: more water means more units per dose, not more doses per vial. For any other vial or dose, use the calculator below.
How many 1 mg vials a cycle takes
| Scenario | Dose | Doses a week | Weeks | Total | 1 mg vials |
|---|---|---|---|---|---|
| Low end of the common protocol | 20 mcg | 7 | 1.5 | 0.22 mg | 1 |
| High end of the common protocol | 50 mcg | 7 | 6 | 2.1 mg | 3 |
Whole vials, rounded up. Plan a cycle with your own numbers in the protocol builder. Keep mixed vials cold and use them within the window in how long reconstituted peptides last; where to inject: subcutaneous injection sites.
IGF-1 LR3 doses used in animal studies
Every published IGF-1 LR3 dose I could verify is from an animal study, using routes and schedules unlike a subcutaneous injection in an adult:
What the studies found:
- Rats: 44 micrograms a day of IGF-1 LR3 matched the growth produced by 278 micrograms a day of native IGF-1 Tomas 1993 - Tomas FM, Knowles SE, Chandler CS et al. Anabolic effects of insulin-like growth factor-I (IGF-I) and an IGF-I variant in normal female rats. J Endocrinol. 1993;137(3):413-21., in the references below.
- Pigs: it lowered blood glucose 2-3 times more potently than native IGF-1, and for longer Tomas 1997 - Tomas FM, Walton PE, Dunshea FR et al. IGF-I variants which bind poorly to IGF-binding proteins show more potent and prolonged hypoglycaemic action than native IGF-I in pigs and marmoset monkeys. J Endocrinol. 1997;155(2):377-86., in the references below.
- Rat detection study: unchanged IGF-1 LR3 disappeared from the blood rapidly after about 4 hours Mongongu 2021 - Mongongu C, Coudoré F, Domergue V et al. Detection of LongR(3) -IGF-I, Des(1-3)-IGF-I, and R(3) -IGF-I using immunopurification and high resolution mass spectrometry for antidoping purposes. Drug Test Anal. 2021;13(7):1256-1269., in the references below.
- Mice: in an Alzheimer’s disease model, mice were given it intranasally for 7 months. It improved body composition but did not preserve memory Engel 2025 - Engel MG, Narayan S, Cui MH et al. Intranasal long R3 insulin-like growth factor-1 treatment promotes amyloid plaque remodeling in cerebral cortex but fails to preserve cognitive function in male 5XFAD mice. J Alzheimers Dis. 2025;103(1):113-126., in the references below.
- Growth-restricted fetal sheep: the infusion did not improve growth, and circulating amino acid levels fell rather than rose White 2025 - White A, Stremming J, Wesolowski SR et al. IGF-1 LR3 does not promote growth in late-gestation growth-restricted fetal sheep. Am J Physiol Endocrinol Metab. 2025;328(1):E116-E125., in the references below.
None of these is a dosing study that a person using IGF-1 LR3 would recognise.
Reconstitution and injection volume: use the calculator
Working out how many milligrams end up in a syringe for a given vial size and diluent volume is arithmetic, not a dosing decision. The dosage calculator performs that arithmetic for whatever numbers you supply.
What is not established
- No published human trial has ever tested IGF-1 LR3 at any dose, frequency or duration. The protocol above is common practice compiled from circulating sources, not a finding from a study.
- No established human half-life. See the main page for why this site does not print one.
- No approved product and no FDA label to defer to. IGF-1 LR3 has no DailyMed listing.
Who should not use it, and the risks
No FDA-reviewed contraindication list exists for IGF-1 LR3. As general context, mecasermin is the only FDA-approved IGF-1 drug. It is contraindicated in patients with malignant neoplasia or a history of malignancy. Its label warns that severe hypoglycaemia, including hypoglycaemic seizures, has been observed with treatment.
IGF-1 LR3 acts on the same receptor pathway. Anyone with diabetes, a history of hypoglycaemia, or active or past cancer was not studied and should not use it. The same goes for anyone pregnant or breastfeeding, and for children. Full detail on this extrapolation, and on the unanswered question of IGF-1 signalling and abnormal tissue growth, is on the main IGF-1 LR3 page.
Related
IGF-1 LR3 dosage calculator
Preset to a 1 mg vial and 20 mcg, the low end of the common protocol. Enter your own vial size, water and dose to get the syringe units to draw.
Your vial
Printed on the vial. There is no standard size - enter what yours says.
This changes how much you draw - never how many doses the vial holds.
100 units per mL. 1 unit = 0.01 mL. This is what almost every insulin syringe sold is, in every barrel size.
Capacity only. A 1 mL U-100 syringe holds 100 units - the scale decides that, not the barrel.
Draw this much
= 0.04 mL on a 1 mL U-100 syringe
- Concentration
- 500 mcg/mL
- Exact volume
- 0.04 mL
- Dose you actually get
- 20 mcg
- Doses per vial(unaffected by water volume)
- 50
Where to buy IGF-1 LR3 for research
Each vendor is checked against my vendor checklist.
1.Next Level PharmFeatured
1 mg vial
- No FDA warning letter found
- Names its testing lab
- Batch COAs published
- Takes card payment
2.BioEdge Research Labs
1 mg vial
- No FDA warning letter found
- Names its testing lab
- Batch COAs published
Common questions
What is the usual IGF-1 LR3 dose?
The protocol most often used is 20-50 mcg by subcutaneous injection once daily, typically in the morning with food to offset the glucose-lowering effect. It runs for roughly 1.5 to 6 weeks, with a 4-6 week break between cycles. That is common practice compiled from circulating protocols, not a dose any regulator or human trial has established. No controlled trial has given IGF-1 LR3 to a person and measured a dose at all.
Has IGF-1 LR3 been dosed in any study at all?
Yes, but only in animals. Growing rats were given 44 micrograms a day by mini-pump for 14 days. Rats were given a single 100 microgram per kg intramuscular injection in a detection study. Pigs were given single injections of 20 and 50 micrograms per kg to measure blood-glucose lowering. Mice were given it intranasally for 7 months. A 2024 study infused growth-restricted fetal sheep at 1.17 micrograms per kilogram per hour for one week. The same group had infused normal fetal sheep at 6.6 micrograms per kilogram per hour for one week. None of these is a human dose.
Can the animal doses be converted into a human dose?
No, and this page will not do that math. The delivery methods differ: continuous infusion, a single injection or an intranasal spray in animals, versus repeated subcutaneous injections in an adult. The species differ too, and no published pharmacokinetic study has validated a conversion between the two. A converted number would manufacture a precision the evidence does not support.
How often and for how long should IGF-1 LR3 be used?
There is no published human interval or duration to report. IGF-1 LR3 has no established human half-life in the literature this site could verify, and a dosing interval would normally be built from that figure. In rats given a single intramuscular injection, unchanged IGF-1 LR3 disappeared from the blood rapidly after about 4 hours. That is an animal detection finding, not a human half-life.
How do I work out reconstitution and injection volume?
That is arithmetic, not a dosing decision, and it depends on a specific vial's concentration and diluent volume. The dosage calculator does that math for any numbers you enter but does not choose a dose. The dosage chart on this page gives units for the common protocol by vial size. That protocol is common practice, not trial-established.
Who should not use IGF-1 LR3?
No FDA-reviewed contraindication list exists, because no such review has happened. As general context, mecasermin is the one approved IGF-1 drug that acts on the same receptor. It is contraindicated in patients with malignant neoplasia or a history of malignancy, and it warns of severe hypoglycaemia. Anyone with diabetes or a history of hypoglycaemia, active or past cancer, anyone pregnant or breastfeeding, and children were not studied with IGF-1 LR3 and should not use it.
What are the main risks?
No long-term human safety data exist for IGF-1 LR3 itself. Mecasermin's label warns that severe hypoglycaemia, including hypoglycaemic seizures, has been observed with treatment. In pigs a single injection of IGF-1 LR3 lowered blood glucose 2-3 times more potently than native IGF-1. Neither is a measurement in people given IGF-1 LR3. IGF-1 signalling also drives cell growth, an unanswered safety question no study has tested for IGF-1 LR3.
When should I stop and get medical care?
Get emergency care (call 911 in the US) for signs of severe hypoglycaemia (confusion, seizure, loss of consciousness) or a severe allergic reaction. For a suspected overdose or reaction that is not an emergency, contact Poison Control at 1-800-222-1222. This page is not a substitute for a clinician who knows your history.
References (7 sources)
Bibliographic detail is fetched from PubMed, not written by me - so a citation here cannot drift from the paper it names. Study design comes from PubMed's own tags rather than my judgement.
- 1.White A, Stremming J, Wesolowski SR et al. IGF-1 LR3 does not promote growth in late-gestation growth-restricted fetal sheep. Am J Physiol Endocrinol Metab. 2025;328(1):E116-E125.StudyPMID 39679943full text
- 2.Tomas FM, Knowles SE, Chandler CS et al. Anabolic effects of insulin-like growth factor-I (IGF-I) and an IGF-I variant in normal female rats. J Endocrinol. 1993;137(3):413-21.StudyPMID 8371075
- 3.Tomas FM, Walton PE, Dunshea FR et al. IGF-I variants which bind poorly to IGF-binding proteins show more potent and prolonged hypoglycaemic action than native IGF-I in pigs and marmoset monkeys. J Endocrinol. 1997;155(2):377-86.StudyPMID 9415072
- 4.Mongongu C, Coudoré F, Domergue V et al. Detection of LongR(3) -IGF-I, Des(1-3)-IGF-I, and R(3) -IGF-I using immunopurification and high resolution mass spectrometry for antidoping purposes. Drug Test Anal. 2021;13(7):1256-1269.StudyPMID 33587816
- 5.Engel MG, Narayan S, Cui MH et al. Intranasal long R3 insulin-like growth factor-1 treatment promotes amyloid plaque remodeling in cerebral cortex but fails to preserve cognitive function in male 5XFAD mice. J Alzheimers Dis. 2025;103(1):113-126.StudyPMID 39610283full text
- 6.INCRELEX (mecasermin) injection label - Indications and Usage, and Section 5.1 Hypoglycaemia warning- US National Library of Medicine, DailyMedlabel
- 7.America's Poison Centers - confirms the US poison help hotline number given on this page (1-800-222-1222).- America's Poison Centersother