Anabolic-androgenic steroids carry serious, well-documented risks to nearly every major organ system in men, with the cardiovascular system taking the hardest hit. A large study published in Circulation in 2025 found that steroid users faced roughly three times the risk of heart attack and heart failure compared to non-users, and nearly nine times the risk of cardiomyopathy. But the damage extends well beyond the heart. Liver tumors, collapsed sperm counts, kidney scarring, tendon ruptures, severe acne, and measurable changes in brain structure all appear in the research literature on steroid use. The picture that emerges is one of system-wide strain, where gains in muscle size come at the cost of quiet, compounding harm across the body.
The Heart Takes the Biggest Hit
Cardiovascular disease is the most dangerous consequence of steroid use and the best-studied one. The 2025 study in Circulation, which tracked steroid users against matched controls, reported adjusted hazard ratios that paint a stark picture: about three times the risk of acute heart attack, roughly 2.4 times the risk of blood clots in the veins, more than twice the risk of arrhythmias, and close to nine times the risk of cardiomyopathy, a condition in which the heart muscle weakens and can no longer pump blood effectively.1PubMed. Cardiovascular Disease in Anabolic Androgenic Steroid Users Case reports over the years have consistently flagged these same events, along with pulmonary embolism and sudden cardiac death.2PubMed. Androgenic anabolic steroid abuse and the cardiovascular system
One mechanism behind this is direct structural remodeling of the heart. The HAARLEM study, a prospective trial following amateur steroid-using bodybuilders, found that left ventricular mass increased by about 28 grams during a steroid cycle, and that this thickening correlated with weekly dose.3PubMed Central. Anabolic Androgenic Steroids Induce Reversible Left Ventricular Hypertrophy and Cardiac Dysfunction. Echocardiography Results of the HAARLEM Study A thicker heart wall sounds like a stronger heart, but it actually stiffens the muscle, reduces its ability to fill properly, and sets the stage for arrhythmias and eventual failure. Steroids also push the blood into a more clot-prone state by activating platelet aggregation and impairing the ability of blood vessels to dilate.2PubMed. Androgenic anabolic steroid abuse and the cardiovascular system
Cholesterol and Blood Pressure Go in the Wrong Direction
Steroids reliably distort the lipid profile in a way that accelerates artery disease. A case study of a bodybuilder who cycled on and off steroids over several years documented HDL (“good”) cholesterol dropping by about 90% and LDL (“bad”) cholesterol rising by about 100% during active use.4International Journal of Sports and Exercise Medicine. Extremely Low HDL Cholesterol and Increased LDL Cholesterol Induced by the use of Anabolic Steroids in a Body Builder: A Case Study Those are extreme numbers from a single case, but the overall direction, HDL crashing while LDL climbs, is one of the most consistent findings across steroid research. This lipid pattern is widely accepted as a driver of atherosclerosis, the buildup of fatty plaques in artery walls.
Blood pressure tends to rise as well, though the evidence here is somewhat mixed. Some studies show clear, dose-dependent increases in both systolic and diastolic blood pressure that track with duration of use.5PubMed Central. Cardiovascular manifestations of anabolic steroids in association with demographic variables in body building athletes Others have found weaker associations. When hypertension does appear, it likely results from the kidneys retaining more sodium under the influence of androgens. Readings as high as 195/110 mm Hg have been recorded in otherwise healthy athletes with no other identifiable cause for the elevation.6PubMed Central. Cardiac and Metabolic Effects of Anabolic-Androgenic Steroid Abuse on Lipids, Blood Pressure, Left Ventricular Dimensions, and Rhythm Put the lipid changes and the blood pressure together, and you have two of the biggest modifiable risk factors for heart attack and stroke both moving in the wrong direction at the same time.
Liver Damage Ranges from Subtle to Surgical
The liver processes most oral steroids, and it shows the wear. The damage ranges from quietly elevated liver enzymes, which many users dismiss, to hepatic adenomas, benign tumors that can hemorrhage. One well-documented case involved a 27-year-old bodybuilder who developed multiple liver tumors that bled into his abdomen and required surgical removal of part of his liver. The remaining tumors shrank after he stopped steroids, but when he relapsed several years later, the tumors grew back and bled again.7PubMed Central. Anabolic steroid abuse causing recurrent hepatic adenomas and hemorrhage
A 2022 review in the World Journal of Gastroenterology described the current understanding of how steroids injure liver cells: they disrupt the liver’s antioxidant defenses, ramp up bile acid production to harmful levels, and trigger excessive growth of liver cells.8PubMed Central. Anabolic androgenic steroid-induced liver injury: An update Oral steroids, particularly those modified with a 17-alpha-alkyl group to survive first-pass metabolism, are the biggest culprits. Injectable forms bypass the liver initially, so they tend to cause less hepatic stress, but they are not harmless to the liver either. Peliosis hepatis, a condition where blood-filled cysts form inside the liver, and cholestatic jaundice, where bile flow stalls, are also in the case report literature for long-term users.
Sperm Counts Can Crash to Zero
When you flood the body with external testosterone or its derivatives, the brain’s signaling loop that drives natural testosterone production shuts down. The pituitary gland stops sending the hormones that tell the testes to make sperm and testosterone. The result is predictable: the testes shrink, sperm production plummets, and natural testosterone levels collapse. This condition, sometimes called anabolic steroid-induced hypogonadism, is one of the most common consequences of use.
A study of 45 men seeking fertility treatment after steroid use found that the median initial sperm concentration was zero. Over half of the men had no detectable sperm at all. After six months of medical treatment, about a third of those men with initial azoospermia remained severely impaired, and more than a quarter still had zero sperm.9Fertility and Sterility. Fertility outcomes in men with prior history of anabolic steroid use Only a small fraction achieved normal sperm counts after half a year of treatment. Some case reports do show more encouraging recoveries. One 44-year-old man went from zero sperm to nearly 16 million per milliliter in under four months with targeted hormonal therapy.10PubMed Central. Spermatogenesis recovery treatment in less than four months from zero to almost 16 million sperms per milliliter after several cycles of steroids in 44-year-old healthy man But that kind of outcome is far from guaranteed.
A scoping review of recovery from steroid-induced hypogonadism found that testicular atrophy and sperm production generally improve over months to years, but the timeline depends heavily on age and the extent of prior use. Libido typically returns over several months, though users often report it feels less intense than during active steroid use. One effect that tends to stick around is gynecomastia, the growth of breast tissue. Recovery from that is considered unlikely without surgery.11PubMed Central. Physical, psychological and biochemical recovery from anabolic steroid-induced hypogonadism: a scoping review
Kidney Scarring from the Inside
The kidneys receive less attention than the heart or liver in discussions of steroid risk, but they are not spared. A systematic review in BMC Nephrology identified a specific pattern of kidney damage called focal segmental glomerulosclerosis (FSGS) in steroid users. The suspected pathways include the extra lean mass forcing the kidney’s filtering units to work harder, the overproduction of a scarring-promoting protein, and increased oxidative stress.12PubMed Central. The potential effects of anabolic-androgenic steroids and growth hormone as commonly used sport supplements on the kidney: a systematic review In plain terms, the kidneys get pushed beyond their design limits, and scar tissue starts replacing functional tissue.
A case report documented this in a man who had used performance-enhancing drugs for ten years alongside a high-protein diet and intense training. His kidney function markers improved once he stopped all performance-enhancing substances and began treatment.13Polish Annals of Medicine. Focal segmental glomerulosclerosis as a rare side effect of combined anabolic-androgenic steroid use, high-protein diet and high-intensity anaerobic training The encouraging part is that early-stage kidney damage appears at least partially reversible. The troubling part is that FSGS is often silent until substantial function is lost, meaning users may not know anything is wrong until the damage is advanced.
Aggression, Mood, and the Brain
The “roid rage” stereotype is exaggerated but not baseless. A meta-analysis of experimental studies found that steroid administration increased self-reported aggression in healthy men, though the effect was small.14PubMed Central. Anabolic-androgenic steroid administration increases self-reported aggression in healthy males: a systematic review and meta-analysis of experimental studies The reality is more nuanced than a simple chemical switch being flipped. Research comparing steroid-using weightlifters to non-users found that while elevated testosterone levels were associated with increased aggression on both subjective and objective measures, the steroid users also showed higher rates of pre-existing personality traits linked to antisocial and borderline personality disorders.15Journal of Forensic Sciences. Measures of Aggression and Mood Changes in Male Weightlifters With and Without Androgenic Anabolic Steroid Use In other words, the personality profile a person brings to steroid use matters at least as much as the steroids themselves. Someone already prone to impulsive or aggressive behavior may be more susceptible to the mood-altering effects, while someone with a stable temperament may notice little change.
Beyond mood, there is evidence that long-term steroid dependence can change the physical structure of the brain. A neuroimaging study comparing steroid-dependent men to non-dependent users found significantly thinner cortex across multiple regions in both hemispheres, including areas in the frontal, temporal, parietal, and occipital lobes.16PubMed Central. Structural brain characteristics of anabolic–androgenic steroid dependence in men Cortical thinning in frontal regions is associated with reduced impulse control and decision-making capacity, which raises the concerning possibility that prolonged steroid use may erode the very cognitive faculties a person needs to decide to stop using.
Tendons That Cannot Keep Up with Muscles
Steroids make muscles grow faster and stronger, but tendons do not necessarily follow the same curve. This mismatch creates a real vulnerability. A cross-sectional study of steroid-using athletes explored two hypotheses for why tendon ruptures appear more common in this population. The first: muscles simply outgrow their tendons, so the tendon faces forces it was never built to handle. The second: steroids may damage the tendon’s collagen structure directly, making it stiffer, less flexible, and more prone to failure. Animal studies lean toward the second explanation, showing collagen abnormalities in steroid-exposed tendons, though one small human study using electron microscopy found no obvious structural differences.17PubMed Central. Ruptured Tendons in Anabolic-Androgenic Steroid Users: A Cross-Sectional Cohort Study Both hypotheses may be right simultaneously. Separate research on patellar tendons in steroid users found differences in collagen remodeling and higher tendon stress, suggesting the tissue adapts differently to training under the influence of androgens.18PubMed. Effect of androgenic-anabolic steroids and heavy strength training on patellar tendon morphological and mechanical properties
This is a risk that rarely makes the headline lists of steroid side effects, but it deserves attention. A torn Achilles or patellar tendon can end a lifting career more decisively than any other complication, and it tends to happen suddenly and without warning, often during a heavy lift that the muscles can handle but the tendon cannot.
Skin Problems and Metabolic Disruption
Acne is one of the most visible and common side effects of steroid use. It can range from ordinary breakouts to acne fulminans, a severe and sudden eruption that produces deep, painful, ulcerating lesions. A viewpoint published in JMIR Dermatology highlighted acne fulminans as a clinical indicator of possible steroid abuse and noted the role that body-image-focused social media plays in driving young men toward steroid use in the first place.19PubMed Central. Cutaneous Manifestations of Anabolic-Androgenic Steroid Use in Bodybuilders and the Dermatologist’s Role in Patient Care In one reported case, a 22-year-old bodybuilder developed severe ulcerated acne that paradoxically worsened with isotretinoin, a medication typically used to treat severe acne, leading to the formation of pyogenic granuloma-like lesions.20PubMed Central. Severe ulcerated ‘bodybuilding acne’ caused by anabolic steroid use and exacerbated by isotretinoin
On the metabolic side, steroid use impairs how the body processes sugar. A study of powerlifters who used steroids found that they had diminished glucose tolerance compared to non-users, despite producing significantly more insulin after a sugar load. Their insulin responses were even higher than those of sedentary obese individuals, pointing to steroid-driven insulin resistance.21PubMed. Insulin resistance and diminished glucose tolerance in powerlifters ingesting anabolic steroids Over time, this kind of metabolic stress could pave the road toward type 2 diabetes, particularly in users who also carry excess body weight or have a family history of the disease.
What Reverses and What Does Not
One of the most common questions former steroid users have is whether the damage undoes itself. The answer varies by organ system. Cardiac changes appear to be at least partially reversible. The HAARLEM study data and a review in Best Practice & Research Clinical Endocrinology & Metabolism both indicate that the thickening of the heart walls and worsened heart function seen during active use tend to normalize after cessation.22Best Practice & Research Clinical Endocrinology & Metabolism. Common symptoms associated with usage and cessation of anabolic androgenic steroids in men That is genuinely good news, and it gives clinicians an argument to present to users who are considering quitting.
Blood cell counts, HDL cholesterol, and most hormones of the pituitary-testicular axis also appear to recover after more than a year off steroids, though some former users continue to show mildly elevated liver enzymes and depressed testosterone production even after prolonged abstinence.23PubMed. Reversibility of the effects on blood cells, lipids, liver function and hormones in former anabolic-androgenic steroid abusers Sperm production, as discussed earlier, generally recovers but on a timeline of months to years, and not fully in all men.9Fertility and Sterility. Fertility outcomes in men with prior history of anabolic steroid use Gynecomastia, once the breast tissue has developed, is the standout exception: it generally does not resolve on its own.11PubMed Central. Physical, psychological and biochemical recovery from anabolic steroid-induced hypogonadism: a scoping review
The key variable across all of these systems is duration and dose. Short cycles at moderate doses leave lighter footprints. Years of heavy use, the pattern that characterizes most of the alarming case reports, produce deeper damage that takes longer to heal and may not heal completely.
Injection Risks and Infections
About half of steroid users inject their drugs intramuscularly, and the injection itself introduces risks that have nothing to do with the steroid’s pharmacology. A case report described a thigh abscess in a 26-year-old steroid user who did not use sterile technique and shared multi-dose vials with two other lifters. The literature links steroid injection to abscesses caused by several bacterial species, and to transmission of HIV, hepatitis B, and hepatitis C.24PubMed. Abscess related to anabolic-androgenic steroid injection These infections are largely preventable with clean technique and single-use equipment, but the underground and often secretive nature of steroid use means prevention practices are inconsistent.
What Is Actually in the Vial
Because most steroid use occurs outside the medical system, the products themselves are a source of risk. A systematic review and meta-analysis examining black-market steroids found that roughly a third of products were outright counterfeit and another third were substandard, meaning the vial might contain the wrong compound, the wrong dose, no active ingredient at all, or extra undeclared substances.25PubMed Central. Fake anabolic androgenic steroids on the black market – a systematic review and meta-analysis on qualitative and quantitative analytical results found within the literature A separate pilot study that chemically analyzed 23 steroid samples submitted by users found that 13% contained substances different from what the user expected.26PubMed Central. The world’s first anabolic-androgenic steroid testing trial: A two-phase pilot combining chemical analysis, results dissemination and community feedback Broader reviews of underground market products have found adulteration rates ranging from 18% to 86%, with potential contamination by heavy metals or microorganisms.27Asian Journal of Research in Medical and Pharmaceutical Sciences. Anabolic Androgenic Steroids from Underground Market: drug Quality and Implications for Research
This means that even a user who has carefully considered the known pharmacological risks of a specific compound may be taking something entirely different. The unpredictability makes dose management impossible and turns every injection into a gamble on what is actually entering the body.
The Polypharmacy Problem
Steroid use rarely happens in isolation. A metasynthesis of studies on substance use among steroid users found a wide range of additional drugs in play, organized into 13 distinct categories. The most commonly used adjuncts were alcohol and cannabis, followed by cocaine, growth hormone, human chorionic gonadotropin (hCG, used to restart testicular function), amphetamines, clenbuterol, ephedrine, insulin, and thyroid hormone. Analgesics including opioids, dietary supplements, and diuretics also appeared frequently. Users took these substances for three broad reasons: to amplify the effects of steroids, to manage their side effects, and for recreation or sexual enhancement.28PubMed Central. Polypharmacy among anabolic-androgenic steroid users: a descriptive metasynthesis
This layering of drugs complicates every risk discussed in this article. Insulin use alongside steroids, for example, carries the risk of fatal hypoglycemia. Diuretics can compound kidney stress. Stimulants like cocaine and amphetamines pile additional cardiovascular strain on top of a system already burdened by steroid-induced hypertrophy and lipid distortion. And because most of these substances also come from unregulated sources, the quality concerns described above apply to them too. When researchers or clinicians encounter a steroid-related health crisis, untangling which substance caused which harm is often impossible. The practical consequence for users is that the real-world risk profile of a steroid “cycle” is almost always worse than the risk profile of the steroids alone, because the steroids are almost never alone.