Limited · human
This case report describes a 54-year-old male who presented to the emergency department with acute left upper quadrant pain and vomiting, and was found to have atraumatic splenic rupture (ASR) — a rare, potentially fatal condition. The patient had recently been using two performance-enhancing compounds: MK-677 (ibutamoren), a growth hormone secretagogue, and RAD-140 (testolone), a selective androgen receptor modulator (SARM). CT imaging confirmed a large perisplenic hematoma. Initial management with splenic artery embolization provided only transient stabilization, and the patient ultimately required emergency laparotomy with total splenectomy. Histopathology revealed extensive splenic infarction and features suggestive of an underlying vascular malformation. The authors speculate — without establishing causation — that the pharmacological effects of RAD-140 and MK-677 on androgen receptor signalling and IGF-1 pathways may have contributed to splenic complications, drawing an analogy to the known association between anabolic steroids and peliosis. No prior literature directly links these compounds to splenic pathology. The report highlights the importance of prompt diagnosis and surgical management of ASR. Key limitations include the single-patient design, inability to confirm causality, and presence of a potential pre-existing vascular malformation as a confounding factor.
Limited · human
This study investigated the detection of ibutamoren (MK-677), a growth hormone secretagogue, in human hair samples to aid forensic interpretation of anti-doping hair test results. Two scenarios were examined: (1) a single 10 mg oral dose administered to a male volunteer, with hair collected 4 weeks later; and (2) hair collected from an individual who had consumed 60 capsules of 10 mg ibutamoren over 90 days, also sampled 4 weeks after discontinuation. Researchers developed a liquid/liquid extraction method using bicalutamide-D4 as an internal standard, with a validated linear range of 0.5–250 pg/mg and a limit of detection of 0.1 pg/mg. The study found that a single 10 mg dose produced a positive hair result at 1.3 pg/mg in the 0–1 cm segment, while the prolonged-use scenario yielded 224 pg/mg in the 0–4 cm segment. The authors conclude that these findings establish, for the first time, ibutamoren's incorporation into human hair and provide reference concentration ranges to support interpretation of hair test results in anti-doping proceedings. Key limitations include the very small sample size (essentially two subjects) and the non-controlled nature of the second case.
Clinica chimica acta; international journal of clinical chemistry · Aug 2025DOI ↗ Limited · human
This paper presents a case report of a man in his early 30s who developed transaminitis (elevated liver enzymes) after taking MK-677, an oral growth hormone secretagogue, for approximately two months. MK-677 has been growing in popularity as a performance-enhancing supplement. The patient was otherwise healthy, with no other apparent causes for liver injury identified. Following discontinuation of the supplement, liver function tests gradually returned to normal levels, suggesting a causal relationship between MK-677 use and the hepatotoxic event. The authors highlight that while known side effects of MK-677 include oedema, increased appetite, and muscle pain, reports of hepatotoxicity associated with its use are rare. This case adds to the limited literature on potential adverse hepatic effects of MK-677. Key limitations include the single-patient design, lack of a liver biopsy or formal causality assessment score (e.g., RUCAM), inability to fully exclude confounders such as contaminants in the supplement, and the inherent difficulty in establishing definitive causality from a single case report.
BMJ case reports · Jul 2025DOI ↗ Limited · human
This case report describes a 40-year-old male who developed bilateral gynecomastia and biochemical hypogonadotropic hypogonadism after approximately six months of using commercially available performance-enhancing supplements. Laboratory analysis of the three supplements identified several banned performance-enhancing drugs (PEDs): RAD-140 (a selective androgen receptor modulator), MK-677 (a growth hormone secretagogue), and cardarine. In vitro testing also revealed undisclosed hormones — testosterone, estradiol, and growth hormone — present in all three products. Liquid chromatography-mass spectrometry further identified an uncharacterized compound eluting near the testosterone peak. Upon cessation of all supplements, the patient experienced full clinical and biochemical resolution of his symptoms, including normalization of gonadotropin and testosterone levels. The authors argue this case underscores the importance of clinicians considering commercially available supplements as potential covert sources of exogenous PEDs and steroid hormones. Key limitations include the single-patient design, which precludes generalization, the inability to isolate which specific compound(s) caused the adverse effects, and the lack of confirmed identity of the uncharacterized coeluting compound.
JCEM case reports · Aug 2024DOI ↗ Limited · human
This case report tracked a single 25-year-old recreationally active male who self-administered LGD-4033 (a selective androgen receptor modulator) and MK-677 (a growth hormone secretagogue) daily for five weeks. Blood work and body composition (via DXA) were collected before, during, and after the cycle, while muscular strength and skeletal muscle androgen-related biomarkers were assessed during the cycle and compared cross-sectionally against data from non-using trained males. The study observed increases in total body mass, lean mass, and fat mass during the cycle, alongside adverse changes in bone mineral content and density, serum lipids (notably a 40% rise in LDL and a 36% drop in HDL), and liver enzymes (ALT rose over 200%). Total and free testosterone and sex hormone-binding globulin fell markedly during the cycle. Most biomarkers returned toward baseline post-cycle, though total cholesterol, LDL, total fat mass, and bone area did not fully recover. Follicle-stimulating hormone remained below clinical reference ranges even post-cycle. Compared with non-users, the subject showed higher intramuscular testosterone and dihydrotestosterone but lower androgen receptor content, alongside greater strength. Key limitations include the single-subject design, lack of a control group, and reliance on cross-sectional comparisons for intramuscular and strength data, making causal inferences unreliable.
Experimental physiology · Nov 2022DOI ↗ Limited · human
This study compared the growth hormone (GH) response elicited by a single oral dose of LUM-201 (ibutamoren/MK-0677), a GH secretagogue receptor agonist, to responses from standard diagnostic GH stimulation tests (arginine, glucagon, clonidine, L-dopa, and insulin-induced hypoglycemia) in 68 pediatric subjects enrolled in a pediatric growth hormone deficiency (PGHD) clinical trial. The study found that LUM-201 produced significantly greater GH responses than the conventional secretagogues, with median peak GH of 15.0 ng/mL versus 5.5 ng/mL for standard tests (p-value not fully captured in abstract but reported as statistically significant). Notably, the larger GH responses to LUM-201 were most pronounced in subjects who also showed higher peak GH responses to conventional testing, suggesting a functional somatotroph reserve may be required. The authors concluded that LUM-201 may represent a potential oral treatment alternative to injectable recombinant human GH (rhGH) in a subset of PGHD patients who demonstrate adequate acute GH responses to LUM-201. Limitations include the lack of a placebo-controlled design, relatively small sample size, and the single-dose comparison design which does not assess long-term growth outcomes.
Hormone research in paediatrics · Mar 2022DOI ↗