Is Ostarine Suitable for Women? The Ultimate Guide

Ostarine, or MK-2866, is a selective androgen receptor modulator (SARM) becoming increasingly popular among researchers, fitness enthusiasts, athletes, and bodybuilders.

Ostarine is illegal for cosmetic use in most countries; however, some individuals unlawfully utilize it to enhance muscle building and fat burning.

Several athletes have been caught taking ostarine, as it is known to increase muscular strength and power without causing excessive weight gain or extracellular water retention.

What Are the Advantages of Ostarine for Women?

• Muscle gain
• Strength results
• Fat loss
• Energy

Muscle Gain

The benefits of ostarine for women are essentially the same as the benefits for men. However, certain effects are more pronounced and promising in women, such as the level of muscle gain.

We have observed women gaining significant amounts of muscle on ostarine, compared to only modest increases in men.

One of our female patients gained approximately 25 pounds from an ostarine-only cycle, with a dosage starting at 7 mg/day and ending at 15 mg/day. She also reported retaining all of her results post-cycle. In contrast, men commonly report gaining only 5–10 pounds of lean muscle.

This anabolic effect may be more pronounced in women because they only have 5% of the testosterone levels of men (1). Thus, when ostarine binds to the androgen receptor with tissue selectivity, enabling significant increases in free testosterone, women are more susceptible to higher spikes in protein synthesis and positive nitrogen retention within the muscle cells.

Therefore, as men already have roughly 20 times more endogenous testosterone than women, their potential for muscle hypertrophy is less from SARMs.

In our observations, women who have previously used anabolic steroids experience less muscle growth than women with no experience taking performance-enhancement drugs (PEDs).

Strength Results

We have observed notable strength results from ostarine in both men and women, with increases of 30 pounds on main compound lifts being common during the first cycle.

Women who perform in sports may also be able to exercise for an extended duration with increased intensity during ostarine treatment. Furthermore, muscle recovery can vastly improve, with delayed onset muscle soreness (DOMS) being a less frequent occurrence.

Fat Loss

According to our patients, ostarine’s muscle-building effects are superior to its lipolytic effects in both men and women. However, its ability to reduce subcutaneous and visceral fat mass has resulted in it being utilized in cutting cycles as well as bulking cycles.

Ostarine has a positive effect on insulin sensitivity in research, which is contrary to other PEDs. Therefore, ostarine may be an effective compound for studies relating to diabetes management.

Energy

Some women struggle with low energy, fatigue, and a lack of motivation, particularly when they have estrogen dominance.

Ostarine significantly reduces estrogen, improving overall well-being due to the stimulation of dopamine receptors.

The estradiol levels of one of our female patients can be viewed below, pre- and post-ostarine cycle.

Estradiol before	Estradiol after
725 pmol/L	141 pmol/L

A woman’s results on ostarine can be determined by her past experience, or lack thereof, with PEDs. For example, a natural woman who administers ostarine for the first time may experience superior results compared to a woman who has cycled SARMs or Anavar (oxandrolone) previously.

Several benefits can be experienced with each ostarine cycle, such as increased:

• Energy
• Motivation
• Mood

Disclosure: We do not accept any form of advertising on Inside Bodybuilding. We monetize our practice via doctor consultations and carefully chosen supplement recommendations, which have given our patients excellent results.

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Note: Sports Technology Labs’ products are regularly tested by MZ Biolabs, an independent laboratory with a US Drug Enforcement Administration Schedule III license.

Can Ostarine Cause Issues in Women?

• Virilization in high doses
• Fluctuations in sex drive
• Cholesterol increase
• Raised ALT and AST enzymes

Virilization in High Doses

Some of our female patients report no side effects from ostarine cycles. This is a common outcome for women who utilize conservative dosages and adhere to standard cycle protocols.

However, other women on ostarine can experience:

• Hair thinning
• Acne vulgaris
• Clitoral hypertrophy

Women who experience the above side effects often consume high dosages or take prolonged cycles.

A woman visited our clinic reporting clitoral enlargement and increased body hair following a high-dose ostarine cycle, which is detailed below.

Week(s)	Ostarine dosage
1	12.5 mg
2-12	25 mg

Her side effects normalized after several weeks post-cycle.

Women who have previously experienced masculinization may be more prone to virilizing side effects from ostarine. Additionally, women who stack ostarine with other SARMs or anabolic steroids may increase the risk of defeminization.

Fluctuations in Sex Drive

Fluctuations in sex drive are typically the main side effects women experience on ostarine.

Thus, on-cycle, a woman’s libido can be amplified, which may be advantageous or disadvantageous depending on the user. If this becomes an issue, women can reduce their dosage, which will reduce their sex drive.

Women are likely to experience sensitivity from ostarine, particularly in their breasts and vaginal area. Such alterations in libido and sensitivity often normalize post-cycle. A transient effect may occur post-cycle, where a woman experiences low libido until her endogenous testosterone levels normalize. This process commonly takes 1–2 weeks.

Nicholas Downey, Ph.D., states that he was “surprised” after observing “minimal suppression” from ostarine in rodent research, with luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels largely remaining stable. In comparison, “RAD-140, LGD-4033, and S23 have demonstrated suppression in rats,” says Dr. Downey.

Anecdotally, in patients, we have observed notable reductions in LH and testosterone from ostarine, with FSH levels remaining stable. Below are the before and after readings of LH and testosterone from a female patient who cycled ostarine for 7 weeks.

LH before	LH after	Testosterone before	Testosterone after
14 U/L	5 U/L	2.5 nmol/L	1.3 nmol/L

Her cycle, including dosages and duration, can be viewed below.

Weeks	Ostarine dosage
1-7	12.5 mg/day

The duration for a woman’s testosterone and LH levels to normalize can depend on the dosage used, cycle length, and genetics.

Post-cycle therapy (PCT) is an additional protocol that women can use to shorten this recovery period.

Cholesterol Increase

A female patient of ours had blood tests taken pre- and post-ostarine cycles, and although her overall health remained excellent, she experienced a modest increase in cholesterol. An 8-week preclinical study also found that ostarine elevated cholesterol levels, raising the risk of hypercholesterolemia (2).

The United States Anti-Doping Agency (USADA) states that ostarine and other SARMs may increase the risk of a heart attack or stroke.

Despite our patient experiencing an insignificant elevation in cholesterol, women suffering from hypertension will be more vulnerable to harm

Raised ALT and AST Enzymes

Liver enzymes may increase with ostarine use, potentially causing hepatic inflammation. We performed liver function tests on a patient who had cycled ostarine for three months, leading to a diagnosis of cholestatic injury (3).

A typical scenario is that a woman’s ALT and AST enzymes rise notably on-cycle and promptly fall back within a normal range post-cycle. However, women with elevated liver enzymes prior to taking ostarine are more vulnerable to hepatic injury during treatment.

The Food and Drug Administration (FDA) also warns that ostarine can cause acute liver injury or failure, which is typically detected during liver function tests.

Cycle Information for Women

Weeks	Ostarine dosage
1-2	7 mg/day
3-10	10 mg/day

The above ostarine cycle is common among female beginners who have not cycled ostarine previously.

Some women increase the dosage to 12 or 15 mg/day and extend the cycle to 12 weeks. However, our patients report the severity of side effects increasing with higher doses.

A researcher’s decision to increase the dose may depend on a woman’s sensitivity to the drug. Even in an instance where a female subject is tolerating ostarine acceptably, high dosages administered too soon increase the risk of harm. Instead, increased doses after a few weeks allow the body sufficient time to transition.

Typically, doses exceeding 10 mg/day can yield minimal additional results. Therefore, 10 mg/day is a generous dose, especially for women who purchase SARMs from companies that formulate their products at over 98% purity. Such high-quality sources often provide third-party certificates of analysis to authenticate the purity level.

“SARMs, including ostarine, will decrease the body’s production of endogenous testosterone,” says Rand McClain, D.O. Furthermore, Dr. McClain states that testosterone levels are likely to recover post-cycle, particularly in reasonably aged and healthy individuals.

Following ostarine supplementation, women may experience a few symptoms indicative of lower testosterone, including:

• Decreased mood
• Lower libido
• Reduced energy levels

The extent of the above side effects is typically mild and, in most cases, unnoticeable according to our female patients. Therefore, most women do not utilize PCT following an ostarine-only cycle, as this SARM is not typically very suppressive.

However, women with existing low testosterone may be more prone to tiredness and decreased libido after taking ostarine.

In this instance, a woman may benefit from supplementing with dehydroepiandrosterone (DHEA), with the dose tailored to her needs based on her testosterone score and side effect severity.

What is the Optimal Dose Frequency?

Based on our testing, ostarine’s half-life is 24 hours (4), so only 1 dose per day is required for optimal results. This should be taken at approximately the same time each day.

Our female patients report the effects being almost immediate, with them often feeling more aggressive and energetic just minutes after a dose.

Is it Advisable for Women to Consume Ostarine With Meals?

In research, SARMs, including ostarine, have occasionally caused dyspepsia (5). Thus, taking SARMs with food may preserve the stomach lining.

In clinical settings, taking ostarine with food may be particularly beneficial to individuals who are prone to indigestion, abdominal pain, or nausea.

Conclusion: Is Ostarine Suitable for Women?

Ostarine is not suitable for women because it is a research chemical prohibited for cosmetic use. Girls under 18 years old may be more vulnerable to potential toxicity from ostarine exposure.

Additionally, there is an increased risk of complications if pregnant and breastfeeding women supplement with ostarine.

Based on our female patient observations, ostarine is among the most effective SARMs for improving body composition. We have seen it cause notable muscle growth, with manageable side effects, when taken in conservative dosages.

However, ostarine remains an unapproved substance, and therefore, its long-term side effects are unknown.

We Are Here to Help

If you or someone you know has been exposed to ostarine and requires help with harm reduction or recovery, please contact us. We can conduct a personalized assessment and give recommendations based on the individual’s lifestyle, diet, and health history.

Relevant Research

• SARMs in women: what do we know, and what is still missing?
• Effects of combined treatment with selective androgen and estrogen receptor modulators ostarine and raloxifene on bone tissue in ovariectomized rats
• SARMs have specific impacts on the mouse uterus
• In vitro and in vivo human metabolism of ostarine, a SARM and doping agent
• Nonsteroidal SARMs enhance female sexual motivation
• Ostarine blunts the effect of endurance training on submaximal endurance in rats
• Ostarine increases lean body mass and improves physical performance in healthy elderly subjects
• Activity and safety of ostarine, a novel, oral, SARM, in androgen receptor-positive, estrogen receptor-positive, and human epidermal growth factor receptor 2-negative advanced breast cancer

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