Updated September 2026. SARMs Store sells research compounds only. Nothing on this page is medical advice or an instruction for human use.
Safety is the most searched question about this class of compounds and the one most often answered badly. Forum posts describe SARMs as harmless, mainstream headlines describe them as dangerous, and neither side usually cites anything. The honest position sits between the two and rests on four separate bodies of evidence: the controlled clinical trials, the published case reports, the regulatory record, and the laboratory analyses of what is actually inside products sold online. This guide sets out each of them, because the risk profile of a compound and the risk profile of an unverified bottle of that compound are not the same thing.
What “safe” can and cannot mean here
No selective androgen receptor modulator has been approved as a medicine anywhere in the world. That single fact does most of the work. Approval is the point at which a regulator decides a compound’s benefits outweigh its risks in a defined population at a defined dose. Nothing in this category has cleared that bar, so there is no authority anywhere that has judged any SARM safe for human use, and no supplier can honestly claim otherwise. What does exist is a body of short and medium-term trial data, mostly in older adults and cancer patients, at doses far below those found in retail research products.
What the clinical trials found
The trials are reassuring on tolerability and consistent on three measurable changes.
Hormonal suppression. In the phase I study of LGD-4033 (Basaria and colleagues, Journals of Gerontology, 2013), healthy young men given 0.1, 0.3 or 1 mg daily for 21 days showed dose-dependent falls in total testosterone, free testosterone, sex hormone binding globulin and follicle stimulating hormone. Luteinising hormone fell as well. Values returned towards baseline by around day 56 after stopping. The phase II Ostarine study (Dalton and colleagues, Journal of Cachexia, Sarcopenia and Muscle, 2011) recorded the same pattern at 3 mg daily over 12 weeks, again reversible.
Cholesterol. The most consistent metabolic finding across SARM trials is a fall in HDL cholesterol, seen in both the LGD-4033 and enobosarm studies and dose-related in each. HDL recovered after discontinuation in the trial populations. What nobody has measured is what repeated or longer exposure does to cardiovascular risk, because no trial has run long enough to produce cardiovascular endpoints.
Liver enzymes. At trial doses, liver enzymes were largely unremarkable. The exception is RAD-140: in the first-in-human study of RAD-140 in women with hormone receptor positive breast cancer (LoRusso and colleagues, Clinical Cancer Research, 2022), raised transaminases were the most frequently reported adverse event, and dose escalation was limited by it.
Side effects reported outside the trials
This is where the picture changes. A growing series of case reports describes drug-induced liver injury in people taking bodybuilding products labelled as SARMs. Flores and colleagues published a case series in Hepatology Communications in 2020 describing cholestatic liver injury associated with these products, with jaundice and prolonged recovery. Barbara and colleagues reported liver injury associated with products labelled as RAD-140 and as a RAD-140 plus LGD-4033 combination in ACG Case Reports Journal in 2020. Bedi and colleagues reported a similar case associated with an Ostarine product in the same journal in 2021. In several of these reports the pattern was cholestatic, took months to resolve, and occurred at amounts far above anything used in a trial.
The other commonly reported effects in the literature and in regulatory reporting systems are the predictable consequences of androgen receptor activity: acne, increased aggression, hair shedding in those predisposed, and in women the risk of virilisation with the more androgenic compounds. Andarine has a specific reported visual effect, a yellow tint and difficulty adapting to darkness, which appears widely in user reports but has not been characterised in a controlled human study.
The regulatory record
In October 2017 the US Food and Drug Administration issued a public safety notification warning against SARMs in body-building products, sent warning letters to three companies, and stated that the agency was concerned about the potential for liver injury, increased risk of heart attack and stroke, and life-threatening reactions. That position has not been withdrawn. The MHRA in the UK takes the equivalent line: a SARM offered for human use is an unlicensed medicine, and selling or advertising it that way is an offence.
The contamination problem
The single most important safety finding in the literature is not about pharmacology at all. Van Wagoner and colleagues, publishing in JAMA in 2017, bought 44 products sold online as SARMs and analysed them. Only 52 per cent contained the compound named on the label. Thirty-nine per cent contained a different unapproved drug altogether. Only 41 per cent contained the stated amount of the labelled compound, and around a quarter contained substances that were not declared at all. Several of the liver injury case reports involved products of exactly this kind.
The implication is blunt. A large share of the harm attributed to SARMs in the public record may be attributable to whatever else was in the bottle. That is why batch-specific analysis matters more than any argument about which compound has the best profile.
What is still unknown
There is no long-term human safety data for any compound in this class. There is no cardiovascular outcome data. There is no fertility data beyond short-term hormone measurements. There is no data in healthy young women, and none in adolescents. Anyone telling you a SARM is proven safe is describing a study that does not exist.
Legal status in the UK, 2026
SARMs are not controlled substances under the Misuse of Drugs Act 1971 and are not listed as Class C anabolic steroids. They fall under the Human Medicines Regulations 2012 as unlicensed medicinal products when sold or advertised for human use, which is what the MHRA enforces against. Legitimate UK suppliers therefore sell them strictly for laboratory research. All of the commonly sold compounds are prohibited in sport at all times under the WADA list, most under section S1.2 as other anabolic agents.
How to check a supplier
Given the JAMA findings, verification is the practical safety measure available to a buyer. Ask for the certificate of analysis for the batch you are buying rather than a sample document. It should identify the compound by HPLC or LC-MS, state a purity percentage, and carry a batch number that matches the bottle. Look for UK manufacturing, clear labelling of the amount per capsule, and a research-only notice. Dexterz Labs products are made in the UK, supplied at 90 capsules per bottle, and batch certificates of analysis are being published on the product page as testing is completed.
Frequently asked questions
Are SARMs safer than anabolic steroids? In animal models they show a better ratio of anabolic to androgenic activity. In humans that has never been tested head to head, and steroids have decades more safety data, so the comparison is theoretical.
Do all SARMs suppress testosterone? Every compound that acts as an androgen receptor agonist suppressed the hormonal axis in the trials, in a dose-dependent way. MK-677 and Cardarine are not androgen receptor agonists and did not.
Is liver damage from SARMs common? The published evidence is a series of case reports, not an incidence rate, so nobody can put a figure on it. What the reports show is that it happens, that it can be severe, and that contaminated products are frequently involved.
Does the suppression reverse? In the trials it did, within weeks of stopping, at the low doses studied. No trial has looked at recovery after the amounts sold retail.
Are side effects dose-dependent? Yes, in every trial that used more than one dose.
What is the biggest safety risk? On the published record, buying a product that does not contain what the label says.
Related reading
- Ostarine (MK-2866): the complete research guide
- PCT after SARMs: what the studies show
- Third-party testing: how to read a certificate of analysis
- Are SARMs legal in the UK? 2026 update
Research product line: PCT and cycle support range
Sources: Van Wagoner RM et al., JAMA 2017;318:2004-2010. Basaria S et al., J Gerontol A Biol Sci Med Sci 2013;68:87-95. Dalton JT et al., J Cachexia Sarcopenia Muscle 2011;2:153-161. Flores JE et al., Hepatol Commun 2020;4:450-452. Barbara M et al., ACG Case Rep J 2020;7:e00409. Bedi H et al., ACG Case Rep J 2021;8:e00518. LoRusso P et al., Clin Cancer Res 2022;28:4831-4841. FDA public safety notification, October 2017. WADA Prohibited List 2026.