Yes, anabolic steroids (commonly called “gear”) carry serious health risks across nearly every major organ system. The damage ranges from reversible changes that resolve after stopping to permanent harm, depending on the compounds used, the doses, and how long a cycle lasts. Around 6% of men and 1–2% of women worldwide have used steroids at least once, making this far from a fringe concern.
How Gear Works in Your Body
Anabolic steroids are synthetic versions of testosterone. When they enter your cells, they bind to androgen receptors, which then travel into the cell nucleus and switch on genes responsible for building muscle protein. This is why muscle grows faster and recovers quicker on a cycle: the machinery that builds tissue is running at a higher rate than your body could naturally sustain.
The problem is that androgen receptors aren’t just in muscle. They’re in your heart, liver, brain, skin, and reproductive organs. So while gear amplifies protein synthesis in the places you want it, it’s also triggering changes in places you don’t. Every effect discussed below stems from that same basic mechanism: synthetic hormones activating receptors throughout the body at doses far beyond what your endocrine system was designed to handle. Typical medical testosterone replacement delivers about 75 to 100 mg per week by injection. Performance-enhancing cycles commonly involve several times that amount, often stacking multiple compounds.
Heart Damage Is the Biggest Risk
The cardiovascular system takes the hardest hit. A prospective study (the HAARLEM study) tracked steroid users through a full cycle and found that left ventricular mass, the weight of the heart’s main pumping chamber, increased by an average of 28 grams during a single cycle. Both the wall between the heart’s chambers and the back wall of the left ventricle thickened measurably. The heart’s pumping efficiency dropped by about 5%, and the chamber became stiffer, meaning it didn’t relax and fill with blood as well between beats.
The good news from that study: all of those changes reversed after users stopped. But that’s one cycle. Repeated cycles over years create a situation where the heart thickens, partially recovers, thickens again, and may eventually reach a point where the damage sticks. Steroid use also raises blood pressure, increases the concentration of red blood cells (thickening the blood), and shifts cholesterol in a dangerous direction. Together, these changes raise the long-term risk of heart attack and stroke.
Liver Toxicity Depends on the Compound
Not all steroids damage the liver equally. The dividing line is a chemical modification called C-17 alpha alkylation, which is what allows certain steroids to survive passing through the liver so they can be taken as pills. That same modification is what makes them toxic. Oral compounds like oxymetholone, stanozolol, and methandrostenolone have all been linked to prolonged bile flow blockage (cholestasis), blood-filled cysts in liver tissue, non-cancerous liver tumors, and hepatocellular carcinoma.
Injectable testosterone preparations like cypionate and enanthate don’t appear to affect liver enzymes at all, and no hepatotoxicity has been reported from standard injectable or topical testosterone. This doesn’t make injectables “safe,” since the cardiovascular, hormonal, and psychological risks still apply. But if someone insists on using gear, the liver risk from oral compounds is categorically worse.
Your Natural Hormone Production Shuts Down
When you flood your body with external testosterone, your brain detects the excess and stops sending the signals that tell your testes to produce their own. This happens through a feedback loop: high androgen levels suppress kisspeptin neurons in the hypothalamus, which in turn shut down the release of the hormones (LH and FSH) that drive testicular function. The suppression is dose-dependent, not an on/off switch, but at the doses used for performance enhancement, natural production essentially flatlines.
After stopping, recovery follows a general pattern. Gonadotropins (the signaling hormones) typically normalize within three to six months. Testosterone itself usually approaches recovery in the same timeframe, though full restoration to pre-use levels is uncertain. Testicular volume, which shrinks during use due to the loss of internal stimulation, takes months to years to return. The psychological side of recovery is less predictable: libido and erectile function generally come back over months, but many men report that their “baseline” never feels as robust as it did on cycle.
Fertility Can Take a Major Hit
Exogenous testosterone causes internal testicular testosterone to plummet by as much as 94%, which devastates sperm production. Up to 40% of men on testosterone become completely azoospermic, meaning no sperm at all in their ejaculate. A pooled analysis of 30 studies found that only 67% of previously healthy men recovered normal sperm production within six months of stopping.
Even with medical treatment to speed recovery, up to 30% of men who were azoospermic may never achieve sperm counts high enough for reliable natural conception. For men who want to use testosterone but preserve fertility, some protocols add HCG (a hormone that mimics the brain’s signal to the testes) during the cycle. Studies have shown this can prevent the dramatic crash in internal testosterone: men receiving HCG alongside testosterone saw only a 7% drop in intratesticular testosterone instead of a 94% drop. But this kind of careful medical management is rare among people using gear recreationally.
Mood, Aggression, and “Roid Rage”
The psychological effects of steroids are real, though they vary widely between individuals. Studies of steroid users have consistently found increased aggression, irritability, and violence during on-cycle periods that disappear during off periods. Users report significantly more fights and verbal aggression, including toward partners, while actively using. The intensity of these effects correlates with testosterone levels in the blood.
The withdrawal period brings its own set of problems. Roughly 10–12% of users in early studies developed major depression after stopping steroids. A study of female athletes found 40% reported depressive symptoms during withdrawal, though fewer met the full clinical criteria for a depressive episode. The first few months after stopping carry the highest risk for mood disturbance, which makes sense: your natural testosterone is bottomed out, you’re losing the muscle and energy you had on cycle, and your brain chemistry is adjusting to the absence of supraphysiological hormone levels.
Post-Cycle Therapy Has Limited Evidence
Most steroid users rely on post-cycle therapy (PCT) to restart their natural hormone production, typically using drugs that block estrogen receptors or inhibit estrogen production. Survey data from 470 men found that PCT reduced cravings to restart steroids, withdrawal symptoms, and suicidal thoughts by 50–60%. That sounds promising, but there are no randomized controlled trials supporting PCT for steroid-induced hormonal shutdown. The clinical studies that do exist show mixed results, and the improvements in sexual function scores were not statistically significant compared to simply waiting it out.
There’s also a practical problem: most PCT drugs are obtained through the same underground channels as the steroids themselves, so users often can’t verify what they’re actually taking. Some users report that PCT worsened their psychiatric symptoms rather than helping. The medical community has not endorsed any specific PCT protocol, and recommending one based on current evidence would be premature.
Reversible vs. Permanent Damage
Some effects of gear use are clearly reversible after a single cycle. Cardiac structure normalized in the HAARLEM study. Hormones generally recover within months. Sperm production usually returns. But “usually” and “generally” carry real weight here. Up to 30% of men may have lasting fertility impairment. Full testosterone recovery is uncertain. And each additional cycle stacks risk on top of incomplete recovery.
The effects most likely to become permanent include liver damage from oral steroids (tumors and structural changes to liver tissue don’t always resolve), cardiovascular remodeling from years of repeated cycles, and hormonal disruption from prolonged or heavy use. The dose-response relationship is consistent across nearly every study: higher doses and longer cycles produce more severe changes. There is no established “safe” dose for non-medical use.