Andarine (S4) Uses, Dangers & Side Effects

Andarine (S4) Uses, Dangers & Side Effects

Andarine is a SARM developed to treat muscle wasting and osteoporosis. It has shown promise in animal studies, where it increased bone density and muscle mass. But, it was abandoned in early clinical trials as a result of serious safety concerns. Individuals who use it tend to be unaware of these dangers, which can be downplayed in bodybuilding sites. Read on to learn more about this medication and its side effects.

Disclaimer: We highly recommend against using this drug since its effects and safety are unknown. Thus, we’re presenting the available data from the scientific and clinical literature with the aim of helping readers understand the risks involved.

What’s Andarine?

Andarine also referred to as S-4, S-40503, or 8, is a SARM developed with the intent of treating osteoporosis and muscle wasting.

SARMs (selective androgen receptor modulators) are medications that bind to the androgen receptor (AR), which is the main site of activity of this hormone testosterone.

In the first days, Andarine was called the perfect SARM because of high oral bioavailability and great muscle- and bone-building effects (studied in animals).

Phase I human trials with this drug have reportedly been effective but no studies are published. But, further development of the drug was abandoned in favor of Ostarine, another SARM with a similar structure also called S-22.

This was probably due to Andarine’s poor safety profile. It caused vision-related unwanted side effects, which further adds to the long list of reasons for taking this medication.

Mechanism of Action

Andarine has a higher affinity for the androgen receptor (AR) and therefore mimics the effects of testosterone. But, its effects are much stronger in bones and muscles than in reproductive organs. That’s exactly why Andarine and other SARMs are hypothesized to cause fewer side effects compared to anabolic steroids.

Bodybuilders have a tendency to take this unapproved theory as “proof” that they will not need to manage severe testosterone reduction and increased estrogens if they accept SARMs. However, this is far from true.

In reality, the “SARMs selectivity concept” might be wholly false. It’s never been proven, and SARMs such as Andarine and Ostarine never passed on proper clinical trials. SARMs may turn out to be more dangerous than previously thought.

Potential Uses of Andarine

This section focuses on the clinical and scientific study that has been performed on Andarine up to now.

Andarine has never been properly researched in humans.

According to the existing data, its effects are unknown and its potential to cause injury is high.

Andarine (S4) | Everything Gym-Goers Should Know | Ask Muscle

1) May Increase Muscle Mass

This drug was designed to avoid muscle wasting, and animal studies do indeed show that Andarine improves muscle growth and strength in animals.

When given to castrated rats for 4 weeks, Andarine improved muscle weight as DHT (dihydrotestosterone). Moreover, unlike DHT, Andarine caused no breast augmentation, which is a concern when taking steroids.

Twelve weeks after castration, Andarine was able to restore lean body (muscle) mass in rats.

2) May Increase Bone Power and Combat Osteoporosis

Andarine increased bone mineral density and strength in both in castrated male rats and in female rats whose ovaries were removed (this can be a commonly used animal model of osteoporosis).

Andarine may be particularly beneficial in osteoporosis because, along with improving bone density, in addition, it enhances muscle power, which might reduce the chance of falls and fractures.

3) Fat Loss

In female rats whose ovaries have been removed, apart from enhancing bone strength, Andarine additionally decreased body fat.

Side Effects of Andarine

Serious Safety Concerns

Andarine is an unapproved medication with completely unknown effects on the entire body.

SARMs are hypothesized to have fewer side effects than anabolic steroids. This remains unproven.

People today misperceive SARMS such as Andarine as more powerful due to a basic misunderstanding of the available scientific information, which can be hyped in several bodybuilding sites.

However, the “SARMS selectivity theory,” based on which people talk about decreased side effects, has never been proven. SARMs like Andarine never passed proper clinical trials. SARMs might even prove to be more dangerous than many other substances (steroids and testosterone included).

LH (luteinizing hormone) and FSH (follicle-stimulating hormone) boost the creation of reproductive hormones in men and women, and their suppression could suppress ordinary estrogen/testosterone levels. Andarine suppressed LH and FSH in castrated rats where these hormones were raised as a result of castration. But, it had no effect in normal male rats.

All in all, it’s unknown if and how much Andarine would suppress testosterone/estrogen manufacturing in people.

The most typical user-reported unwanted effects are visual issues such as a yellowish tint and problem adjusting to night vision. These vanish after the drug has been discontinued. Higher doses appear to cause stronger side effects. Some users also report depression.

Limitations and Caveats

The safety and effects of Andarine have not been researched in people or the studies are not publically available. This drug was mainly examined in rats.

Even though it’s purchased online, its long-term advantages and risks in humans are unknown.

Legality, Sports, and Doping

Legal Status

Since 2008, the usage of SARMs continues to be considered doping by the US Anti-Doping Agency (USADA), and these drugs are around the World Anti-Doping Agency (WADA) prohibited list.

The use of Andarine in competitive and professional sports is, thus, illegal.

This medication is not approved by the FDA for almost any purpose.


There is no safe dose for this medication since it’s not passed appropriate clinical trials or received approval from any regulatory body.

In rats and dogs, Andarine is bioavailable, using an average half-life of about 200 minutes.

Here we outlined the available dose data out of online communities with the endeavor to warn people about the hazards of taking this antipsychotic medication.

According to consumers, a common dosing range is 50 to 75 mg daily (divided into 3 doses taken with meals). Some begin with lower doses of 25 to 50 milligrams per day. Andarine is frequently cycled.

This drug is unapproved, so the high quality as well as the identity of this item is often highly questionable. In a study of 44 products advertised as SARMs (including Andarine), just 52% actually contained SARMs and several were inaccurately labeled.

We SelfDecode advise speaking to a Doctor Prior to taking any drug, particularly an unscheduled drug with limited long-term safety data in humans