Cardarine + Ibutamoren + Andarine stack

iMuscle Cardarine + Ibutamoren + Andarine is a three-compound bundle from iMuscle that groups Cardarine (GW-501516), MK-677 (Ibutamoren) and Andarine (S-4), 60 capsules in total. iMuscle does not state the strength of any of the three and we do not guess at it. Free Muscle stocks it through the Muscle Market range and supplies it for laboratory research only, not for human consumption, to adults aged 18 and over.

The bundle simply places three compounds in one listing; we make no claim that they do anything together. The page takes each compound in turn: what it is, what research measured, its UK and sporting status, and what its batch certificate should show.

About the compounds in this bundle

Cardarine (GW-501516)

Cardarine, also written GW501516 or endurobol, is a synthetic PPAR-delta agonist developed by GlaxoSmithKline and Ligand for lipid disorders; it is not a SARM. A 2012 twelve-week human trial in subjects with low HDL cholesterol recorded a rise in HDL and a fall in triglycerides, but was not designed to assess long-term safety (Olson et al., 2012). Clinical development was halted after two-year rodent carcinogenicity studies found tumours in multiple organs. Every brand we stock is on the Cardarine collection page.

MK-677 (Ibutamoren)

MK-677, also called ibutamoren or L-163,191, is an oral ghrelin receptor agonist and growth hormone secretagogue, not a SARM. In a 2008 two-year randomised trial in 65 healthy older adults, fat-free mass rose by about 1.1 kg versus placebo, with increased appetite, fasting glucose, insulin resistance and oedema also recorded (Nass et al., 2008). It has never been approved. See the MK-677 collection page.

Andarine (S-4)

Andarine, also called S-4, is an early non-steroidal selective androgen receptor modulator from GTx. The published evidence is almost entirely preclinical: in a 2007 study in ovariectomised rats, S-4 preserved bone mass and reduced body fat (Kearbey et al., 2007). It never reached late-stage human trials and has no approval anywhere. Reports of visual disturbance are widely repeated but have not been characterised in a published controlled trial. See the Andarine collection page.

Nothing summarised above is a claim about this product, and no published study has examined these compounds together.

This listing

• Brand: iMuscle
• Compounds: Cardarine (GW-501516), MK-677 (Ibutamoren) and Andarine (S-4)
• Form: capsules
• Pack size: 60 capsules in total across the bundle
• Strength per compound: not stated by the manufacturer
• Bundle basis: one listing for three compounds; no combined effect is claimed
• Use: laboratory research only, not for human consumption, adults 18 and over

With no stated strength, total milligrams per pack cannot be calculated and we do not estimate it. The single-compound iMuscle listings carry a label strength: iMuscle Cardarine GW-501516, iMuscle Ibutamoren MK-677 and iMuscle Andarine S-4. How to set label strengths against each other is explained in price per milligram.

Cardarine, MK-677 and Andarine in the UK: buying, legal status and what to check

Searches such as "cardarine UK legal", "MK 677 UK buy" and "MK677 UK supplier" ask two things: may each compound be sold in Britain, and how would a buyer know what a listing holds?

The legal position, compound by compound

None of the three is a licensed medicine in the UK (MHRA) or an authorised food supplement. They are not controlled drugs and may be sold to adults for laboratory research, the only basis for this listing. The limits concern what they may be sold as: not as a medicine or food, and not with directions for use or a promised result.

All three are banned in tested sport at all times. MK-677 has a page of its own on MK-677 legal status in the UK, and the SARM class is introduced in What are SARMs? The 2026 research guide.

What official medicines laboratories have found

These three compounds are among the molecules official medicines laboratories report most often. Over five years, the falsified medicines working group of the official medicines control laboratory network, whose contributors included a laboratory at the MHRA, pooled 354 results on 324 samples of SARMs, metabolic modulators and growth hormone secretagogues from 14 laboratories in 13 countries, most of them from illegal distribution (Barrios et al., 2025). Ibutamoren, ligandrol, ostarine, cardarine and andarine were the five molecules reported most often. About a quarter of the products were presented as dietary supplements, which the authors flagged because a buyer may not realise that an unapproved pharmaceutical is inside. A name on a pot is a claim; only analysis of the lot tests it.

What a checkable listing shows, and where this one stands

• A named manufacturer and a named UK seller. Made by iMuscle; sold and dispatched by FreeMuscle LTD, a UK company in Scunthorpe.
• A stated strength for every compound. Not given by iMuscle for this bundle, so it does not meet this check; the single-compound listings above do.
• Batch paperwork for each of the three compounds. iMuscle certificates appear here only when the manufacturer provides them for the stock on our shelves.
• No directions for use and no promised outcomes. None appear on this page; research use only, 18 and over.
• Tracked, discreet delivery. Free tracked UK delivery in plain packaging, orders placed before 2pm Monday to Friday processed the same working day, EU delivery in 3-7 working days (delivery).
• A returns route. Unopened items within 30 days (guarantee).

Reviews describe delivery, not contents. Our UK supplier checklist applies the same tests to any shop.

Capsules compared with other forms

Each compound is also sold as a research liquid (hence searches for "MK677 UK liquid") and as powder. None of the three is a peptide. Cardarine (molecular weight 453.5), MK-677 (528.7 as the free base) and andarine (441.4) are small synthetic molecules, and MK-677 was developed as an orally active ghrelin mimetic, which is how the 2008 trial gave it. Why swallowed peptides are a different case is covered in do oral peptides work.

What changes between formats is where the quantity per unit is fixed:

• Capsules have their content fixed when powder is filled into shells. A measured figure per capsule is possible, but one pooled result averages away the spread between individual capsules, and in a bundle it must also be reported separately for each compound.
• Liquids carry a concentration, so the amount in any volume drawn depends on the measuring device, on the compound having fully dissolved and on solvent not evaporating after the bottle is opened.
• Powders leave every portion to the buyer's own scales, so no label figure per unit exists to check.

Salt form matters as well. MK-677 is often supplied as the mesylate salt, which is heavier than the free base, so a label should say which form its milligrams refer to. No study has compared formats for any of these three compounds, and nothing here suggests one form behaves differently in the body. With no strength stated, the usual advantage of a capsule, a checkable figure per unit, is not yet available here.

MK-677 compared with ipamorelin

MK-677 is the most searched of the three compounds in this bundle, and "ibutamoren vs ipamorelin" is the comparison that appears in its search suggestions. The two share a receptor and little else.

Both compounds mimic ghrelin, the stomach hormone that signals hunger, and both prompt the pituitary gland to release its own growth hormone rather than supplying any. The differences lie in the chemistry and in the depth of the record. MK-677 is a compact molecule absorbed from the gut, and its longest trial recorded increased appetite, raised fasting glucose, reduced insulin sensitivity and oedema alongside the change in fat-free mass. Ipamorelin is a chain of five amino acids, two of them in unusual forms, and has no human study of comparable length, so its long-term profile in people is unknown rather than favourable. No trial has given both compounds to the same participants, which means neither can be ranked against the other. Ipamorelin brands are on the ipamorelin collection page; background is in the ipamorelin research guide and MK-677 vs ipamorelin vs HGH.

For the other two compounds, cardarine is often set against SR9009 and andarine against ostarine.

Reading the certificate of analysis for this product

Certificates for this bundle come from iMuscle, not from us, and we display one only when iMuscle provides it for the batch in our stock. Because each of the three compounds may come from its own production lot, request paperwork by compound name. A PDF without a batch number is not a batch certificate. The Janoshik Analytical programme, under which an independent laboratory assays every Free Muscle-brand batch and the certificate is emailed on request, does not extend to iMuscle.

• Identity. An HPLC retention time matched to a reference standard, or an LC-MS mass that fits the formula above. A certificate that names one compound says nothing about the other two.
• Purity. Usually a percentage of HPLC peak area. It grades what the material is, not how much of it a capsule holds.
• Content per capsule. For this bundle there is no label figure to compare it with, so a measured content would be the first statement of strength anyone has made, not a check on one.
• Lot, date and issuing laboratory. Compare the lot code with the label on your pot; the date shows the result's age, and a named laboratory can verify it.

For this brand, a missing field leaves a specific question open. No certificate means nothing independent confirms which compounds are present. Identity without content confirms presence, not quantity. Contact us with the lot numbers and we will tell you what documentation exists. See also how to read a COA and our lab tests page.

Detection, sport and testing

Each compound in this bundle sits in a different section of the WADA Prohibited List, applied in the UK by UK Anti-Doping: andarine in S1, MK-677 in S2 and cardarine in S4. All three are prohibited in and out of competition. Under strict liability an athlete answers for any prohibited substance in their sample, whatever its source.

Cardarine has the most detailed published detection work of the three. It entered the WADA list in January 2009, first categorised as a gene doping substance. The Cologne anti-doping laboratory then identified its two main urinary metabolites, a sulfoxide and a sulfone, and validated a urine screening method with a limit of detection of 0.1 ng/ml that was brought into routine doping controls (Thevis et al., 2010). MK-677 and andarine are also screened for by accredited laboratories, but no verified study cited here gives a window for any of the three after capsules of unstated strength. The accurate answer for each is: detectable, window not established.

Storage, stability and handling

We know of no published shelf-life study for cardarine, MK-677 or andarine in capsule form, so no shelf life is stated here. Any expiry date iMuscle prints is the limit to work to, and a certificate describes a batch only on the day it was tested.

• Check on arrival. Confirm the seal is intact and note each lot number with the date received. Opening a container ends the 30-day return option, which covers unopened items only.
• Store closed, cool, dry and dark. Humidity in kitchens and bathrooms can soften or crack capsule shells. Leave any desiccant sachet in place and close the lid straight after opening.
• Keep each compound traceable. Do not decant, mix or relabel capsules. Once separated from the container, a capsule has no link to its lot number or certificate.
• Handle as laboratory chemicals. Gloves when handling opened capsules or powder, no food or drink in the work area, storage out of reach of children and pets, and disposal as chemical waste under local rules, never in household bins or drains.

Glossary

• PPAR-delta: a receptor inside the cell nucleus that controls genes for using fatty acids as fuel; cardarine was designed to switch it on.
• GHS-R1a: the growth hormone secretagogue receptor, also called the ghrelin receptor, through which MK-677 and ipamorelin act.
• Growth hormone secretagogue: any substance that prompts the pituitary gland to release growth hormone.
• SARM: selective androgen receptor modulator; andarine is one, while cardarine and MK-677 are not.
• Carcinogenicity study: a long-term animal study that looks for tumours; the finding that stopped cardarine's development.
• Free base and mesylate: the uncharged molecule and its heavier methanesulfonate salt; equal milligrams of each hold different amounts of ibutamoren.
• Limit of detection: the lowest concentration a validated method can reliably report, a measure of sensitivity rather than time.
• Strict liability: in anti-doping, the principle that intent does not matter; a positive sample is a violation even when a product was mislabelled.

Related

• Cardarine (GW-501516), all brands and cardarine: what happened in development
• MK-677 (Ibutamoren), all brands and MK-677: what the research says
• Andarine (S-4), all brands
• Ipamorelin, compared above
• iMuscle brand collection
• All bundles

Research use only. Not evaluated by the MHRA, EMA or FDA, not a food supplement, not for human consumption. Sold to adults aged 18 and over. Nothing on this page is medical or dosing advice or a suggestion that the compounds be combined.

References

1. Olson EJ, et al. Lipid effects of peroxisome proliferator-activated receptor-delta agonist GW501516 in subjects with low high-density lipoprotein cholesterol: characteristics of metabolic syndrome. Arterioscler Thromb Vasc Biol. 2012;32(9):2289-94. PMID: 22814748.
2. Nass R, et al. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008;149(9):601-11. PMID: 18981485.
3. Kearbey JD, et al. Selective androgen receptor modulator (SARM) treatment prevents bone loss and reduces body fat in ovariectomized rats. Pharm Res. 2007;24(2):328-35. PMID: 17063395.
4. Barrios MM, et al. SARMs, Metabolic Modulators and Growth Hormone Secretagogues in Suspected Illegal Medicines, Bought as Sport Performance Enhancers: A Retro- and Prospective Study Within the GEON. Drug Test Anal. 2025;17(10):2078-2085. PMID: 40551438.
5. Thevis M, et al. Characterization of two major urinary metabolites of the PPARdelta-agonist GW1516 and implementation of the drug in routine doping controls. Anal Bioanal Chem. 2010;396(7):2479-91. PMID: 19946680.