What it is
LGD-4033, also called Ligandrol, is a SARM (selective androgen receptor modulator). It is an orally active non-steroidal compound that activates the androgen receptor with the goal of building muscle and bone while having less effect on other tissues than traditional anabolic steroids.
Important framing for this forum: LGD-4033 is not a peptide. It is a small synthetic drug and is covered here only for completeness alongside the peptides. It has been studied in early human trials but is not an approved medicine for athletic or cosmetic use anywhere, and it is banned in sport (WADA lists SARMs as anabolic agents). Ligandrol has been one of the most common causes of SARM-related anti-doping violations in athletes, partly through contaminated supplements.
What people use it for
People use LGD-4033 to gain lean muscle mass and strength. It has a reputation as a strong “bulking” SARM. There is no approved indication for physique or performance use; the case for those uses rests largely on a short clinical study plus anecdote.
Typical dose range
There are no approved recreational dosing guidelines. The published healthy-men trial used very low doses (0.1, 0.3, and 1.0 mg/day) and still saw muscle gains and measurable suppression. Reported recreational use is often higher, commonly in the range of around 5 to 10 mg/day, which is well above the studied doses and carries correspondingly more suppression and unknown risk. Higher is not safer.
Note on the calculator: LGD-4033 is taken orally, so there is no reconstitution step the way there is with injectable peptides. The dosing calculator at Peptide Calculator - Reconstitution & Dosage | Buy Peptides UK is built for reconstituting and dosing injectable/lyophilised compounds, so it does not really apply to an oral SARM. It is linked here only for consistency with the rest of the library.
Half-life and frequency
Reported half-life is roughly 24 to 36 hours. That supports once-daily dosing and also means the compound, and its suppressive effect on your hormones, clears over several days after you stop rather than instantly.
How it is taken (oral vs injectable, reconstitution if relevant)
LGD-4033 is taken orally (capsules or oral liquid). There is no reconstitution. Because it is processed by the liver, the liver-injury concern below applies.
Common side effects (including suppression)
- Testosterone suppression: documented in the clinical trial even at low doses (see the next section).
- Liver injury: case reports describe drug-induced liver injury in people using products containing LGD-4033 (sometimes combined with RAD-140), with cholestatic liver damage on biopsy. Injury resolved after stopping in the reported cases, but it is a documented, serious harm.
- Lipids: like other SARMs, LGD-4033 lowers HDL (“good” cholesterol) in trials, which is a cardiovascular concern.
- Headache, fatigue, fluid retention, and mood changes are reported anecdotally.
- Product contamination: independent testing frequently finds SARM products that are mislabeled, under- or over-dosed, or contain something other than what is on the label.
PCT and recovery (SARMs)
LGD-4033 is suppressive. In the placebo-controlled study in healthy young men, even 1.0 mg/day for 21 days lowered total testosterone by roughly 50 percent and significantly reduced free testosterone, LH, and FSH. Recreational doses are usually much higher than 1 mg, so real-world suppression is typically greater than what that trial showed.
What suppression means in practice: while the drug is active your body slows or stops making its own testosterone. That can bring low libido, erectile issues, fatigue, and low mood, and if recovery is not supported it can drag on.
Post-cycle therapy (PCT): a SERM-based PCT (enclomiphene, tamoxifen/Nolvadex, or clomiphene/Clomid) is standard in recreational use to help the natural axis restart. These are prescription drugs with their own side effects. One reassuring data point: in the controlled trial, hormones recovered within about 56 days of stopping, but that was at sub-milligram doses for only 21 days. Higher doses for longer are not guaranteed to recover as cleanly or quickly.
The only honest way to track this is bloodwork: total and free testosterone, LH, FSH, oestradiol, liver enzymes (ALT/AST), and a lipid panel, ideally before, during, and after.
Evidence grade
Weak-to-moderate, and only for short-term effects. There is one decent short placebo-controlled study in healthy men showing lean-mass gains and reversible suppression over 21 days at low doses. Beyond that, evidence for the higher doses and longer cycles people actually use is anecdotal, and the liver-injury reports are documented. So a narrow, short-term effect is reasonably evidenced, while the way it is commonly used is not.
Honest unknowns
- Long-term safety in healthy users is unknown.
- Suppression and recovery at the higher, longer-duration doses people actually use are not characterised by good data.
- True rate of liver injury is unknown; case reports establish it occurs.
- Cardiovascular impact of sustained HDL reduction is unclear.
- Real-world product purity and dosing are unreliable, which undermines even careful protocols.
Research use only. Not medical advice. 18+.