Dianabol (methandrostenolone) is an oral anabolic steroid that increases muscle size and body weight primarily by shifting the body into a state of enhanced protein building. In a controlled trial published in The Lancet, men taking Dianabol during weight training gained an average of 3.3 kg (about 7.3 pounds) of lean body mass over six weeks, with no increase in fat. It remains one of the most widely recognized performance-enhancing drugs in sports history, but its effects extend well beyond muscle growth, impacting the liver, heart, hormonal system, and fertility.
How Dianabol Works in Muscle Tissue
Dianabol is a modified form of testosterone designed to amplify the muscle-building (anabolic) effects while reducing some of the masculinizing (androgenic) ones. Once absorbed, it binds to receptors in muscle, fat, and reproductive tissue, triggering a cascade that increases how efficiently your body incorporates amino acids into new protein. This process, called protein synthesis, is what drives muscle repair and growth after training.
The other key mechanism is nitrogen retention. Muscle tissue is roughly 16% nitrogen by weight, and when your body retains more nitrogen than it excretes, it stays in a net anabolic state, meaning it’s building tissue rather than breaking it down. Dianabol reverses what’s known as negative nitrogen balance, a catabolic state where the body breaks down more protein than it builds. This is why it was originally developed for medical use: it helped reverse muscle wasting in patients with osteoporosis and promoted skin regrowth in burn victims.
Muscle and Strength Effects
The Lancet trial that tested Dianabol in athletic men used a double-blind crossover design, meaning each subject served as his own control. At 100 mg per day for six weeks, the drug produced a statistically significant increase in body weight, and the researchers confirmed through potassium measurements that the weight gain was confined to lean mass. Muscles increased in size.
Interestingly, the same study found that strength and performance improved over each training period but did not improve significantly more on Dianabol compared to placebo. This suggests that much of the visible size gain comes from increased water and glycogen storage inside muscle cells, along with new protein, rather than a proportional leap in contractile strength. Users commonly report dramatic early weight gain in the first two to three weeks, much of which is water retention that reverses after stopping the drug.
Liver Damage
Dianabol belongs to a class of steroids called C-17 alpha-alkylated compounds. This chemical modification allows it to survive passage through the liver after being swallowed, which is what makes it effective as a pill. It’s also what makes it toxic to the liver.
The liver processes Dianabol on every pass, and the drug stimulates unregulated growth signals in liver cells. Over time, this can cause a condition called cholestasis, where bile flow becomes blocked. Cholestasis from oral steroids resembles the liver problems sometimes seen with high-dose estrogen or birth control pills, and it appears related to disrupted bile salt transport proteins. The result is jaundice (yellowing of the skin and eyes), dark urine, and itching.
Liver enzyme elevations from anabolic steroids are typically modest. ALT and alkaline phosphatase levels usually stay below two to three times the upper limit of normal and can sometimes appear normal even when jaundice is present. That makes blood tests an unreliable early warning. With prolonged use, oral anabolic steroids are linked to more serious outcomes, including liver cysts and, in rare cases, liver tumors driven by the same unregulated growth stimulus in liver cells.
Hormonal Shutdown and Recovery
Taking Dianabol suppresses your body’s natural testosterone production. The brain detects high levels of androgens in the bloodstream and responds by dialing down the hormonal signals (LH and FSH) that tell the testes to produce testosterone and sperm. The degree of suppression depends on dose and duration, but users taking doses far above physiological levels experience near-complete shutdown.
Recovery after stopping is possible but slow and often incomplete. A scoping review in Endocrine Connections mapped out the typical timeline:
- Testosterone: Near-complete recovery over months, but full return to pre-use levels may not happen even after years of cessation.
- LH and FSH (brain signaling hormones): Most studies show recovery to baseline within 2 to 16 weeks, though projected full recovery can take 10 to 20 months.
- Sperm production: Usually recovers completely but takes months to years. Sperm count returns first, followed by motility, then normal shape. Fertility rates eventually normalize.
- Testicular size: Near-complete recovery expected over months to years, with minimal remaining difference by one year.
- Libido and erectile function: Return to baseline is expected over months, but users commonly report that baseline feels less potent than what they experienced on the drug.
- Gynecomastia (breast tissue growth): Recovery is not likely. Once breast tissue has developed, it typically requires surgical removal.
That last point catches many users off guard. Dianabol converts to estrogen in the body, and the resulting breast tissue growth is often permanent.
Cardiovascular Effects
Anabolic steroids, including Dianabol, shift cholesterol in a harmful direction. They suppress HDL (the protective form) while raising LDL (the harmful form), creating a lipid profile that accelerates plaque buildup in arteries. Dianabol also promotes water and sodium retention, which raises blood volume and blood pressure. For users who already have borderline cardiovascular risk factors, this combination increases the chance of heart-related complications over time. The cardiovascular effects are generally reversible after stopping, but years of use can cause structural changes to the heart that are harder to undo.
Other Side Effects
Beyond the major organ systems, Dianabol produces a range of secondary effects driven by its androgenic and estrogenic activity. Acne and oily skin are common, as the drug stimulates the same sebaceous glands that testosterone does. Hair loss accelerates in men who are genetically predisposed to male-pattern baldness. Mood changes, including increased irritability and aggression, are frequently reported, though they vary widely between individuals.
Women who take Dianabol face virilization: deepening of the voice, facial hair growth, and menstrual irregularities. Some of these changes are irreversible. Because Dianabol is among the more androgenic oral steroids, these effects can appear quickly even at low doses.
Why It Was Created
Dianabol was developed in the late 1950s by John Ziegler, a scientist at the pharmaceutical company Ciba. It was intended as a therapeutic advancement over testosterone, useful for conditions involving muscle wasting, osteoporosis, and burn recovery. It proved effective in those roles, but its muscle-building properties quickly attracted attention from the athletic world. Ziegler supplied it to the US Olympic weightlifting team at the 1960 Rome Olympics, and from there its use spread rapidly through competitive sports. By the 1970s and 1980s it had become one of the most widely used performance-enhancing drugs in bodybuilding. It is now a controlled substance in most countries and banned by all major sports organizations.