Shaun Ward MSc ANutr
Ligandrol, also named LGD-4033 or Anabolicum, is an oral drug that is defined as a nonsteroidal selective androgen receptor modulator (SARM).
This drug was discovered by Ligand Pharmaceuticals, but is currently being developed by Viking Therapeutics.
Ligandrol has not yet been approved for human use by Food and Drug Administrations, and is not being manufactured by any legitimate pharmaceutical companies.
Despite this, due to the speculated benefits on performance and body composition, athletes and gym enthusiasts have found ways to access ligandrol though online websites and the black market.
This has led to major concerns about the efficacy of ligandrol use, and the potential adverse effects that it may have on human health.
What Are SARMs?
SARMs are a class of drugs that are being promoted as a side-effect free alternative to steroids, such as testosterone.
Standard testosterone administration is commonly used in elderly populations as part of hormone replacement therapy, due to reductions in one’s natural testosterone production from aging.
Low testosterone levels have been found to increase the risk of :
- Libido issues
- Impaired brain function
- Muscle loss
- Reduced strength
- Bone fractures
- Heart disease
However, testosterone administration comes with a long list of side effects including:
- Reduced natural testosterone production
- Water retention
- Liver issues
The majority of these issues are as a result of testosterone binding to receptors outside of the ones which are needed for clinical benefits, such as the androgen receptors on muscle cells.
This is the reason why SARMs were developed, as they are designed to be only activate the receptors on the target tissues of interest (muscle and bone).
At least on paper, by avoiding the unintended stimulation of receptors on other cells, this can significantly reduce, or even eliminate, the side effects that are often seen with standard testosterone use.
The high affinity and selectivity of SARMs exclusively to the androgen receptor has led to speculation about its potential replacement for testosterone in clinical settings, to treat conditions such as sarcopenia and osteoporosis.
This being said, it is key to note that although some preclinical and clinical trials have been conducted on SARMs, no SARM has yet received full clinical approval.
What Is Ligandrol?
Ligandrol is a type of SARM that, much like the others, binds to androgen receptors with high affinity and selectivity.
Chemically, the only difference between ligandrol and other SARMs is that it contains a pyrrolidinyl-benzonitrile core structure.
The initial reason for its development was to act as a therapeutic agent in preventing muscle wasting caused by cancer and aging, and also inhibiting the deterioration of bone density due to osteoporosis.
It is now becoming increasingly popular in athletic populations for increasing muscle mass, strength, and performance, despite its illegality in elite sport. In fact, this drug was well-known to be taken by Florida quarterback Will Grier during the peak of his career – later caught and banned by anti-doping associations.
Does Ligandrol Work?
In short, yes.
In animal models, ligandrol has demonstrated considerable anabolic activity in muscle and bone tissues, and a robust selectivity for muscle when compared to the prostate – although other tissues were not measured.
As an example, in phase 1 clinical trials, daily oral administration of up to 75mg per kg bodyweight in monkeys for over 3 months led to significant body weight gain . However, at the highest dosage range there were concerns over toxicity issues and therefore this group were removed from the study after 7 weeks. Phase 2 clinical trials now use a much smaller dosage to test its effects.
Human trials of ligandrol have also shown great efficacy in skeletal muscle and bone measurements.
Even during very short treatment periods (3 weeks) with small doses (1mg per day), there is clear evidence of the compound’s androgenic activity, as reflected by a 1.2kg increase in lean body mass .
Compare this to the average dose of ligandrol being taken in local gyms, 5-10mg a day, and you can begin to the see the large effects this drug might have.
The mechanisms by which ligandrol works is not well documented. However, based on our understanding of testosterone and its anabolic effects, ligandrol can bind to androgenic receptors and likely induce a number of the following effects:
- Increased muscle protein synthesis 
- Decreased muscle protein breakdown 
- Increased satellite cell production 
- Differentiation of muscle progenitor cells 
At the moment, phase II clinical trials are underway, beginning in 2016, and we are still waiting to see the results from hundreds of patients using ligandrol to treat different health problems.
Is Ligandrol Safe?
The limited research available on ligandrol indicates that it is a safe drug with minimal side effects, however it is crucial to understand that all ligandrol studies so far have either utilized animal models, or used low doses compared to the amounts being used in reality.
1mg of ligandrol has shown no adverse effects on the prostate or natural testosterone production , and has even managed to reduce triglyceride levels in the blood  - although these studies were funded by Ligand Pharmaceuticals, the creators of ligandrol, which could raise a concern for financial bias.
On the other hand, when looking at forum reviews and blood tests from people that have experimented with ligandrol, there have been numerous reports of suppressed natural testosterone levels and a number of other side effects, including:
- Increased LDL (“bad”) cholesterol
- Decreased HDL (“good”) cholesterol
- Water retention
- Increased estrogen levels
- Dry mouth
Such reviews are notable, but it is also important to understand that these people are consuming large amounts (5-10 times more than clinical trials) of ligandrol from unregulated, non-pharmaceutical labs.
At this point, it is of great importance to wait for phase II clinical trials to finish before fully assessing the safety and side effects of ligandrol.
It is advised to avoid the use of ligandrol until the drugs safety has been proven and it has been legalized for use.
Is Ligandrol Legal?
SARMs may or may not be legal to purchase in your home country, and it is advised to check the legality status before purchasing or using this drug.
SARMS are currently not approved by the Food and Drug Administration and are labelled as being “not for human consumption”.
The World Anti-Doping Agency (WADA) and the National Collegiate Athletic Association (NCAA) have also placed SARMs on the “Prohibited List” of substances for competing athletes.
Ligandrol is an oral drug that is defined as a nonsteroidal selective androgen receptor modulator (SARM).
As SARMs have been created to only stimulate the receptors on target tissues (muscle/bone), they are thought to be a much safer alternative to steroids.
Only a limited number of studies have assessed ligandrol, with good evidence that it is effective in animals and humans for increasing lean body mass.
However, the doses used in human trials are low and not comparable to the dose being used in the real world, with many reports of serious safety concerns and side effects in online forums.
The drug is currently not recommended for human consumption by Food and Drug Administrations, and is also banned by world-leading organizations for its use by athletes.