Irisin_Dosage, benefits & legal status
Also known as FNDC5 fragment, fibronectin type III domain containing 5 fragment
The exercise-in-a-pill myokine, and a decade-long argument about whether the tests for it work.
Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.
What is Irisin?
Plain language first. The technical label stays, but it never stands alone.Overview
The exercise-in-a-molecule story. The molecule seems to be real, and the blood tests used to build the case for it were measuring the wrong thing.
Irisin, the proteolytically cleaved extracellular fragment of FNDC5, proposed as an exercise-induced myokine driving thermogenic browning of white adipose tissue. Detection by commercial polyclonal ELISA has documented cross-reactivity with non-specific serum proteins. Presence confirmed by tandem mass spectrometry. No published human administration trial.
What it's used for
Sold for fat loss and metabolic health as a way to copy the effects of exercise.
How does Irisin work?
What it does in the body, and where.Irisin is the best documented case in this library of an entire literature resting on a faulty measurement.
- 01The 2012 claimIrisin was described as cleaved from the muscle protein FNDC5 during exercise and reported to drive browning of white fat, which would make it a chemical version of a workout.
- 02The antibodies were measuring something elseA 2015 paper in Scientific Reports titled irisin a myth rather than an exercise-inducible myokine tested four commercial polyclonal antibodies and found prominent cross-reactivity with unrelated serum proteins, with no bands of the expected size in any biological sample. The authors wrote that this called into question all previous data obtained with commercial ELISA kits.
- 03Mass spectrometry then found it after allA 2015 Cell Metabolism paper detected and quantified circulating human irisin by tandem mass spectrometry, which is a more specific method. The molecule appears to exist.
- 04The measurement problem did not go awayA 2020 follow-up reported that available antibodies still bind non-specific serum proteins and that the mass spectrometry approach requires multi-step preparation introducing uncontrolled variation, and issued an explicit warning against measuring circulating irisin with available methods.
What else is it used for?
Each use below carries its own evidence level. Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.
- Browning of white fat and energy expenditureEarly research
- Insulin sensitivityEarly research
- Bone densityEarly research
- Replacing the metabolic effects of exercisenone
The published record
Papers and trials about Irisin
338 papers tagged human · 152 not reviews or lab · 13 clinical trial publications
81 registered trials · 1 with posted results
Furthest stage reached: Published trials only, 13 clinical trial publications, no phased trial registered
Counted from Europe PMC indexing, not read by a person; a human tag can land on reviews, commentary or lab papers; clinical trial publications is the narrower count. 500 papers and 81 trials indexed in detail.
At a glance
Four things to know about Irisin
Evidence
Category
Weight loss and metabolic
Common vial
Varies
Half-life
Nothing published
How much, and do you cycle it?
The range, and whether you take breaks.Research only, not established. Not established No range
No schedule has been studied for this compound in people.
Nothing publishedNo figure
No half-life has been published for administered irisin in people. Given the documented difficulty of measuring it in blood at all, any figure quoted deserves scrutiny about how it was measured.
You can compare this against the whole library to see where it sits.
How do I dose and price it?
Enter your vial and your dose. Pick a mix. We show the draw and the cost.The vial holds a fixed amount of drug. Adding more water does not make more drug, it just spreads it thinner, so you draw a bigger number on the syringe for the same dose.
Choose your mix
Measuring the water1 mL = one full 100-unit syringe.
How do you store it?
Before mixing, and after.Dry powder in the freezer or fridge. Once mixed, fridge, and use within about a month.
Unmixed lyophilized Irisin keeps for a long time cold. Once you add water the clock starts: most reconstituted vials hold up for roughly 28 to 30 days at fridge temperature. Keep it out of light, and do not freeze it after mixing.
What are the side effects and cautions?
Known cautions and warnings for this compound.Who should avoid it
- Pregnancy or breastfeeding
- Anyone treating this as a substitute for exercise, which no study supports
- Anyone who wants established safety data, because none exists for this compound in humans
Stop and get help
- Signs of an allergic reaction, including spreading hives, facial or throat swelling, or trouble breathing
- Redness, heat, or pus at the injection site, which can signal infection
- Anything unusual, since there is no known safety profile to compare it against
Common effects
- Unknown. No study has recorded what this commonly causes in people
- Redness, soreness, or a small bump at the injection site
Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.
Is Irisin approved?
And where the numbers on this page come from.No. Irisin is not approved for any use, anywhere. It is sold labeled for laboratory research only, and there is no legal route to buy it for human use.
- Approval statusResearch only
- RouteUnder the skin (subcutaneous)
- Checked24 August 2026
- DoseFrom community reports. No regulator or trial established this dose.
- Vial sizeFrom what vendors typically list; not a recommendation.
- SourcesNone traced yet.
What has happened recently
We have not yet written a full regulatory note for this compound. The status above is current as of the date shown.
You can compare this against the whole library, or read how to check a seller.
If you're weighing Irisin, it's worth reading Setmelanotide (Imcivree), Spexin, and 5-Amino-1MQ in the same class.
The exercise-in-a-pill myokine, and a decade-long argument about whether the tests for it work.
- Dose
- Research only
- How often
- Not established
An approved daily shot for rare genetic forms of obesity.
- Dose
- 2 up to 3 mg per day (start low, increase slowly)
- How often
- Daily
An appetite peptide found by computer search, still almost entirely in animals.
- Dose
- Research only
- How often
- Not established
A capsule studied for speeding up metabolism and burning fat.
- Dose
- 2.5 up to 5 mg per day injected (the capsule dose is far higher, see below)
- How often
- Daily, cycled
Guides for this compound
- How to Reconstitute a Peptide
Mix peptide powder with bacteriostatic water, step by step.
- How to Read an Insulin Syringe
Read the units, convert to millilitres, and draw the exact dose.
- mcg vs mg: The Peptide Dosing Mistake to Avoid
Your vial says mg and your protocol says mcg. Here is the conversion and how to check it.
- How to Read a Peptide COA
What the purity number does and does not tell you, and how to spot an edited report.
- How to Vet a Peptide Vendor
Independent COAs, HPLC purity, and the red flags that mean walk away.
Sources
No primary source has been traced for this compound yet. Treat everything on this page as unverified until one is. How we grade evidence
Beyond these, 581 records are indexed. Browse the records