YK-11 is one of the strongest compounds in the SARM family — but it’s also one of the least forgiving when it comes to improper dosing. Originally developed as a synthetic steroidal SARM with myostatin-inhibiting properties, YK-11 shows powerful effects on muscle hypertrophy and strength. However, its aggressive androgenic activity means that even moderate doses can trigger testosterone suppression, liver stress, and other side effects.
If you’re going to run YK-11, you need to know:
→ What the optimal daily dosage is
→ How long your cycle should be
→ How to split doses for maximum effect
→ How to stack it safely (or avoid stacking)
→ What to take post-cycle to recover fully
Let’s start with the most important question: what’s a safe daily dose of YK-11 for performance enhancement?
What Is YK-11?
YK-11 is a synthetic steroidal SARM (Selective Androgen Receptor Modulator) first described in 2011 by Japanese researcher Yuichiro Kanno. It is structurally similar to dihydrotestosterone (DHT) and behaves more like a hybrid anabolic steroid than a traditional non-steroidal SARM like Ostarine or LGD-4033.
What makes YK-11 stand out is its dual mechanism:
→ It binds to the androgen receptor (AR) to promote muscle growth
→ It inhibits myostatin, a protein that normally limits the size and number of muscle cells
By suppressing myostatin and increasing follistatin expression, YK-11 may allow for greater muscle growth potential than other SARMs — but it comes at a cost: higher risk of side effects, liver toxicity, and testosterone suppression.
“YK-11 functions as a potent anabolic agent by blocking myostatin and mimicking DHT activity at the androgen receptor,” explains Dr. Y. Kanno in his foundational study (Kanno, Biological and Pharmaceutical Bulletin).
Because of its unique activity and lack of human safety data, YK-11 should be treated more like an oral anabolic steroid than a typical SARM, especially when planning dosage, stacking, and recovery.
Recommended YK-11 Dosage for Beginners and Advanced Users
Because YK-11 behaves more like an oral steroid than a traditional SARM, dosing must be conservative and closely monitored. Higher doses do not always yield better results — and often increase the severity of side effects, including testosterone suppression and liver strain.
➤ Beginner Dosage (First-Time Users)
→ 5–10 mg per day, taken orally
→ Split into 2 smaller doses (e.g., 5 mg AM / 5 mg PM) to maintain stable levels
→ Cycle length: 4–6 weeks max
This dosage range is ideal for users stacking YK-11 with other SARMs like Ostarine (MK-2866) or Ligandrol (LGD-4033) and seeking moderate muscle gain with fewer side effects.
➤ Intermediate to Advanced Dosage
→ 10–15 mg per day, split into two doses
→ Still limited to 6 weeks max due to liver and hormonal strain
→ Always run full PCT post-cycle
This dosage is used by more experienced lifters looking for maximum hypertrophy and stacking YK-11 with other compounds such as RAD-140 or MK-677.
“YK-11’s anabolic potency increases steeply above 10 mg/day, but so does the risk of suppression and liver toxicity,” warns Dr. R.A. Smith in his 2020 anabolic compound overview (Smith, Journal of Androgen Research).
➤ Women and YK-11 Use
YK-11 is not recommended for women due to its strong androgenic activity and DHT-like side effects (virilization, deepening voice, hair growth). There are no studies confirming safety or efficacy in female users.
For women seeking lean mass or fat loss support, safer alternatives include:
→ Cardarine (GW-501516)
→ Ostarine (MK-2866)
→ L-Glutamine for recovery and muscle preservation
Best Time to Take YK-11 and How to Dose It Properly
Timing and dosing protocol play a key role in both the efficacy and side effect management of YK-11. Due to its short half-life and oral methylation, it’s best to split your daily dose into two equal parts to maintain more stable blood levels and reduce the risk of hormonal crashes or spikes.
➤ Split-Dose Protocol (Recommended)
→ Take half of your daily dose in the morning, and the other half in the evening
→ Example: If running 10 mg/day, take 5 mg around 8 AM and 5 mg around 8 PM
→ This helps avoid sharp peaks that can stress the liver and androgen receptors
“Splitting the YK-11 dose minimizes hormonal volatility and may reduce androgenic or hepatotoxic side effects,” notes Dr. Michelle Arnot in her peptide and SARM usage review (Arnot, Peptide Science Review).
➤ With or Without Food?
→ YK-11 is fat-soluble, so taking it with a meal that contains healthy fats (like eggs, salmon, or Clean Carbs) may increase absorption
→ Avoid taking it on an empty stomach, especially if you’re prone to digestive sensitivity or nausea
➤ Pre-Workout Dosing?
While some users experiment with taking YK-11 pre-workout, this is not recommended due to its delayed effect. YK-11 does not provide acute energy or pump — and pre-workout dosing can lead to side effects (agitation, joint tightness) during training.
For better pre-workout performance, stack with:
→ Kre-Alkalyn® for strength and ATP support
→ Citrulline Malate for nitric oxide and blood flow
How Long Should a YK-11 Cycle Last?
Because YK-11 is a methylated oral compound with steroid-like properties, longer cycles dramatically increase the risk of testosterone suppression, liver toxicity, and side effects. That’s why most users — even experienced ones — keep their cycles short and tightly controlled.
➤ Optimal Cycle Length
→ 4–6 weeks is the standard for YK-11
→ Never exceed 6 weeks, even at lower doses
→ For first-time users: stick to 4 weeks at 5–10 mg/day
→ Follow with a full 4-week PCT using Clomid or Nolvadex
“YK-11’s suppressive profile and oral hepatotoxicity make it unsuitable for extended cycles beyond six weeks,” explains Dr. S. Connelly in his androgen safety analysis (Connelly, SteroidScience.org).
➤ Post-Cycle Bloodwork Timing
→ Bloodwork should be done 1 week after your cycle ends and again 3–4 weeks after PCT
→ Monitor:
→→ Total Testosterone
→→ Free Testosterone
→→ LH & FSH
→→ Estradiol
→→ AST, ALT (liver enzymes)
→→ SHBG, IGF-1 if stacking with MK-677
➤ Time Between Cycles
A good rule of thumb: “Time on = Time off.”
→ For a 6-week cycle, take 6–8 weeks off (including PCT) before considering another round
→ During your off time, support hormonal health with:
→→ DHEA for androgen restoration
→→ ZMT™ for sleep, testosterone, and cortisol control
→→ L-Glutamine for recovery and immune support
Can You Stack YK-11 With Other Compounds?
Yes — YK-11 can be stacked, but with caution. Because it already carries strong anabolic and androgenic effects, stacking should be reserved for experienced users who understand how to manage compound synergy, hormonal stress, and post-cycle recovery.
Poorly designed stacks can lead to extreme testosterone suppression, elevated liver enzymes, joint discomfort, and hormonal crashes post-cycle.
➤ Best Compounds to Stack With YK-11
➤ Ostarine (MK-2866)
→ Great for beginners or recomp phases
→ Helps protect lean mass and joints
→ Reduces muscle breakdown during cutting
→ Stack dosage: 10–20 mg/day Ostarine + 5–10 mg/day YK-11
➤ Ligandrol (LGD-4033)
→ Synergistic strength and mass builder
→ Be cautious: both suppress testosterone significantly
→ Stack dosage: 5–10 mg/day LGD + 5 mg/day YK-11 (max 6 weeks)
➤ MK-677 (Ibutamoren)
→ Elevates GH/IGF-1, improves sleep, appetite, and recovery
→ Does not increase testosterone suppression
→ Works well with YK-11 for size and long-term lean tissue support
→ Stack dosage: 10–20 mg/day MK-677 + 5–10 mg/day YK-11
“Stacks involving YK-11 should be short, conservatively dosed, and include non-androgenic recovery aids like MK-677 to offset suppression,” advises Dr. L. Mahoney in her 2023 SARM stacking report (Mahoney, Peptide Insight).
➤ Avoid These Combinations
→ RAD-140 + YK-11: Too suppressive for most users
→ High-dose LGD + YK-11: Elevated liver strain and hormonal crash risk
→ Anabolics or prohormones: Redundant and toxic; unnecessary with YK-11’s potency
Do You Need a PCT After YK-11?
Yes — a post-cycle therapy (PCT) is absolutely essential after running YK-11.
Because of its strong androgen receptor binding and steroid-like effects, YK-11 suppresses your natural testosterone production, even at lower doses and short cycles. Skipping PCT can lead to prolonged low testosterone, muscle loss, mood crashes, and sexual dysfunction.
➤ Why YK-11 Requires PCT
→ Suppresses LH and FSH through negative feedback
→ Reduces natural testosterone, free T, and sperm production
→ Increases risk of high cortisol and estrogen rebound post-cycle
“YK-11’s suppression rivals that of mild oral steroids and always warrants clinical-grade PCT,” explains Dr. R. Collins, hormone specialist (Collins, Muscle Insider).
➤ PCT Protocol After YK-11
Week 1–4 Post-Cycle:
→ Clomid: 25–50 mg/day
→ OR Nolvadex: 20–40 mg/day
Add-on Support:
→ ZMT™: Enhances sleep, reduces cortisol, and supports LH/FSH production
→ DHEA: Restores androgen precursors in men over 30
→ L-Glutamine: Supports recovery and muscle retention post-cycle
Bloodwork Timing:
→ Test total T, free T, LH, FSH, and estradiol at week 4 post-PCT to confirm recovery
Side Effects at Higher Doses
As with most powerful compounds, the side effects of YK-11 become significantly more severe at higher doses — particularly above 15 mg/day or when cycles are extended beyond 6 weeks. While some users chase faster muscle gains, this comes with a real cost: greater hormonal suppression, higher liver toxicity, and increased androgenic risks.
➤ Accelerated Testosterone Suppression
→ High doses (15–20 mg/day) often result in near-complete shutdown of endogenous testosterone
→ Users may feel great early in the cycle, but often crash hard post-cycle without aggressive PCT
→ Libido, motivation, mood, and recovery all decline rapidly once natural T drops
“Going above 10 mg/day with YK-11 increases suppression exponentially — not linearly,” explains Dr. S. Connelly in his post-cycle recovery protocols (Connelly, SteroidScience.org).
➤ Liver Toxicity
→ YK-11 is 17-alpha alkylated, so oral dosing stresses the liver — especially at higher dosages
→ Elevated ALT and AST enzymes are common with 15+ mg/day
→ Risk of hepatotoxicity increases dramatically if not supported with TUDCA, NAC, and regular bloodwork
➤ Androgenic Side Effects
→ Doses over 10–15 mg/day can increase DHT-like side effects:
→→ Oily skin
→→ Acne
→→ Hair shedding (in genetically prone individuals)
→→ Mood swings or aggression
➤ Estrogen Rebound (Post-Cycle)
→ YK-11 itself doesn’t aromatize, but post-cycle hormone imbalances may cause estrogen to spike if testosterone crashes
→ Result: water retention, gynecomastia, low libido, or mood instability
→ Proper PCT and supplements like ZMT™ help rebalance LH/FSH and keep estrogen in check
Legal Status and Testing Concerns
Like many SARMs, YK-11 lives in a legal gray area. It is not approved for human consumption and is considered an unapproved drug by the FDA. Despite being sold online as a “research chemical,” it is not legal to sell or market for human use in the United States or most other countries.
➤ Is YK-11 Legal to Buy?
→ In the U.S., YK-11 is not classified as a controlled substance, but it cannot be sold as a dietary supplement
→ It is legal to purchase for “research purposes only”, but selling or distributing it for human use violates FDA regulations
→ International laws vary, but most countries follow similar restrictions
“SARMs like YK-11 are not approved for over-the-counter use and are actively targeted by FDA warning letters,” notes the agency in its 2022 SARMs enforcement report (FDA.gov).
➤ Is YK-11 Banned in Drug-Tested Sports?
Yes. YK-11 is explicitly banned by the World Anti-Doping Agency (WADA).
→ It falls under S1.2 “Selective Androgen Receptor Modulators” in the prohibited substances list
→ YK-11 can trigger positive tests for anabolic agents, including abnormal testosterone-to-epitestosterone (T/E) ratios
→ It may also raise red flags in IGF-1 and androgen receptor assays
“YK-11 is among the most potent SARMs prohibited under WADA guidelines due to its strong anabolic profile,” confirms WADA’s 2025 prohibited substances list (WADA).
Bottom line: If you’re a tested athlete, avoid YK-11 entirely. There’s no safe dosing or clearance timeline that guarantees you’ll pass a drug test.
Conclusion: Are You Dosing YK-11 Correctly?
YK-11 is not your average SARM. With its steroidal backbone, myostatin-inhibiting potential, and aggressive androgenic effects, it demands a higher level of dosing precision, support, and recovery planning than most selective androgen receptor modulators.
If you’re going to run a YK-11 cycle, follow these core principles:
→ Start conservatively at 5–10 mg/day, especially if it’s your first cycle
→ Split your daily dose (AM/PM) to maintain stable blood levels
→ Limit your cycle to 4–6 weeks, max
→ Always follow up with a full post-cycle therapy (PCT)
→ Support your liver, hormones, and recovery using targeted supplements like:
→→ ZMT™ for natural testosterone and cortisol regulation
→→ DHEA for androgen balance
→→ L-Glutamine for muscle preservation and gut health
YK-11 can deliver impressive size and strength gains — but it’s not for beginners, not for tested athletes, and not something to use without a solid recovery protocol. If you’re not ready to manage the side effects, consider safer alternatives like Ostarine, MK-677, or a clinically dosed hypertrophy supplement stack.
FAQ: YK-11 Dosage
➤ What’s the best daily dosage of YK-11 for muscle growth?
Start with 5–10 mg/day split into two doses. Only advanced users should consider going up to 15 mg/day — and never beyond that without clinical support.
➤ Can I take YK-11 pre-workout?
Not recommended. YK-11 does not provide acute energy or pump. Take it with food and split doses AM/PM for best results.
➤ How long should I run a YK-11 cycle?
Keep cycles to 4–6 weeks max. Longer cycles increase the risk of testosterone shutdown, liver strain, and androgenic side effects.
➤ What should I stack with YK-11?
For safer stacks, try:
→ Ostarine (for lean mass and joint support)
→ MK-677 (for recovery and GH/IGF-1 support)
→ Avoid stacking with RAD-140 or oral anabolics due to compounding toxicity and suppression
➤ Do I really need a PCT?
Yes. Always. YK-11 suppresses testosterone hard. Use Clomid or Nolvadex for 4–6 weeks post-cycle and support your recovery with ZMT™ and DHEA.
