SARMs Capsules vs Liquid: Stability, Dosing Accuracy and Testing, UK 2026

Updated September 2026. SARMs Store sells research compounds only. Nothing on this page is medical advice or an instruction for human use.

Research compounds in this category are sold in two formats: capsules containing a weighed quantity of powder, and liquids in a dropper bottle. The liquid format is older, cheaper to produce and still common. The choice between them is not a matter of preference. It changes three separate things: how stable the material is over the life of the bottle, how accurately a quantity can be measured from it, and how meaningfully it can be tested. This guide explains each, in formulation terms rather than marketing terms.

What a liquid product actually is

Most compounds sold in this category are poorly soluble in water, so a liquid product is not a simple aqueous solution. It is either a solution in an organic solvent or co-solvent system, or a suspension of undissolved particles in a carrier. The solvents in common use are polyethylene glycol 400, ethanol, propylene glycol and occasionally dimethyl sulfoxide, sometimes blended.

The reason this format exists is convenience for the supplier. Dissolving bulk powder in solvent and filling dropper bottles requires no encapsulation equipment, no content uniformity control and very little capital. The reason it persists is that it is cheap. Neither is a formulation argument.

Stability and degradation

A dissolved molecule is more chemically exposed than a dry powder. In solution it can react with the solvent, with water present in the solvent, with dissolved oxygen and with anything leaching from the container, and those reactions accelerate with heat and with light. This is standard pharmaceutical formulation science and it is why licensed medicines that are unstable in solution are supplied as dry powders for reconstitution rather than as ready-made liquids.

Two specific issues apply to the solvents used here. Polyethylene glycol 400 is hygroscopic, meaning it absorbs water from the air each time a bottle is opened, and PEG can form peroxides over time, particularly when exposed to light and air. Ethanol is volatile, so an ethanol-based product loses solvent gradually through an imperfect seal, which concentrates whatever remains. Neither effect is visible to the buyer.

The honest statement of the evidence is this: there is no published stability programme for any retail SARM liquid. Licensed medicines carry an expiry date derived from formal stability testing under controlled temperature and humidity. Research liquids in this market almost never do. That is an absence of evidence rather than proof of a problem, but the absence is the point, because a capsule of dry powder in a sealed bottle has far fewer ways to go wrong in the first place.

Ακρίβεια δοσολογίας

Measurement from a dropper bottle is the weaker part of the format even when the chemistry is perfect.

If the product is a suspension rather than a true solution, the particles settle. A bottle drawn from without thorough resuspension delivers a weak quantity early in its life and a strong one later, with no way of telling by eye. If it is a true solution, that problem disappears but others remain. Drop volume is not a fixed unit: it varies with the viscosity of the solvent, the diameter of the dropper tip, the temperature and the angle at which the bottle is held. A graduated pipette is better than a drop count but still depends on the user reading a meniscus in a narrow tube, in a viscous liquid that clings to the glass. Residue left in the pipette is a real loss and it varies between users.

A capsule does none of this. It is a discrete unit of a weighed quantity, produced once under manufacturing control and unchanged thereafter. Whatever the number on the label, that number is fixed rather than reconstructed by the user at every use.

Why capsules test more consistently

The testing argument follows directly from the last two sections, and it is the strongest practical point.

A capsule can be assayed as a unit. A laboratory can take capsules from a batch, determine the amount of compound in each and report content per capsule along with an identity confirmation and a purity figure. That is a meaningful statement about what the buyer receives, and it is repeatable, because a later sample from the same batch should give the same answer.

A liquid can be assayed too, but the result describes the concentration of the sample drawn at that moment, from that bottle, in that state of mixing, on that date. It does not establish what a user will draw from a settled bottle three months later, and it does not survive the solvent questions above. The unit the buyer uses is not the unit the laboratory measured.

This is not an abstract concern. Van Wagoner and colleagues, publishing in JAMA in 2017, analysed 44 products sold online as SARMs and found only 52 per cent contained the labelled compound, with only 41 per cent containing the stated amount. Content variability is the documented failure mode in this market, and a format that makes content harder to fix and harder to verify is working against the buyer.

Αποθηκευτικός χώρος

For any format the principles are the same and they are worth stating. Keep material cool, dry, sealed and away from direct sunlight. Heat accelerates chemical degradation and light drives photodegradation and peroxide formation in PEG-based systems. Repeated opening of a hygroscopic liquid introduces moisture with every use. A sealed bottle of capsules stored in a cool dark place has the fewest of these exposures.

Comparison with related formats

Powder sold by weight is the third option and it is the worst of the three for a buyer. It requires a balance with milligram resolution to divide, and ordinary kitchen or jewellery scales are not accurate at that scale, which introduces an error far larger than anything discussed above. Tablets are uncommon in this category because compression requires excipients and equipment that most suppliers do not have. Capsules remain the format that combines a fixed per-unit quantity with a simple, testable manufacturing process.

Legal status in the UK, 2026

Format makes no difference to the legal position. These compounds are not controlled under the Misuse of Drugs Act 1971. Under the Human Medicines Regulations 2012 any of them is an unlicensed medicinal product if sold or advertised for human use, which the MHRA enforces, so they are supplied in the UK strictly for laboratory research. A liquid is neither more nor less lawful than a capsule. All of these compounds are prohibited in sport at all times under the WADA list.

How to check a supplier

Ask what the liquid is dissolved in and in what concentration, and whether the product is a solution or a suspension. A supplier who cannot answer has not formulated the product, only filled it. For any format, require the batch-specific certificate of analysis, identity by HPLC or LC-MS, a purity percentage and a batch number matching the bottle, plus UK manufacture and a research-only notice. Dexters Labs supplies capsules only, made in the UK at a stated amount per capsule with 90 capsules per bottle, each batch independently tested with the certificate linked on the product page.

Συχνές ερωτήσεις

Are liquid SARMs weaker than capsules? Not inherently. The issue is that concentration can change over the life of a bottle and cannot be verified by the buyer, whereas a capsule is a fixed unit.

What are liquid SARMs dissolved in? Usually polyethylene glycol 400, ethanol, propylene glycol or a blend, sometimes with DMSO.

Do liquids expire faster? There is no published stability data either way for retail research liquids, which is itself the problem. Dissolved compounds have more degradation routes than dry powder.

Why do some suppliers only sell liquid? It is far cheaper to produce, requiring no encapsulation or content uniformity control.

How should research material be stored? Cool, dry, sealed and out of direct sunlight, whatever the format.

Can a laboratory test a liquid? Yes, but the result describes that sample at that moment, not every future draw from the bottle.

Σχετική ανάγνωση

• Third-party testing: how to read a certificate of analysis
• Ostarine (MK-2866): the complete research guide
• Researching SARMs for the first time: what to read before buying
• Are SARMs safe? What the evidence says about side effects

Research product: Dexters Labs Ostarine MK-2866 10 mg, 90 capsules

Sources: Van Wagoner RM et al., JAMA 2017;318:2004-2010. Flores JE et al., Hepatol Commun 2020;4:450-452. FDA public safety notification, October 2017. Human Medicines Regulations 2012. WADA Prohibited List 2026.