Clenbuterol: Ultimate Guide for Men & Women

Dr George TouliatosDisclaimer: The following article is for educational purposes only and does not promote the use of illegal substances. If you have any questions or concerns, Dr. Touliatos is currently available for consultation.

Clenbuterol is a β2-adrenoceptor agonist and bronchodilator formulated to treat various breathing disorders, such as inflammatory airway disease (IAD) and recurrent airway obstruction (RAO).

Clenbuterol is an effective anti-asthma medication, having been an approved prescription drug for humans since 1977 in several countries (albeit not the US).

In research, we have seen clenbuterol demonstrate strong anabolic effects in animals, significantly increasing skeletal muscle mass while reducing fat (1).

This has led to bodybuilders purchasing clenbuterol on the black market and utilizing it in cutting cycles alongside other fat-burning steroids.

Hollywood celebrities have also been known to cycle clenbuterol in attempts to transform their bodies in a short space of time.

However, we have found clenbuterol’s effects in humans to be somewhat dissimilar to those in animals. Clenbuterol’s ability to burn fat is undisputed; however, its muscle-building effects in humans are questionable.

Some users report no anabolic effects from clenbuterol, whereas others are adamant about its ability to add lean muscle tissue.

The truth may lie somewhere in the middle, with clenbuterol having anabolic properties, although not to the degree of anabolic-androgenic steroids.

Thus, clenbuterol may help bodybuilders retain muscle when cutting, although significant increases in muscle size and strength are unlikely in our experience. This is therefore more of an anti-catabolic effect than an anabolic one.

Clenbuterol is generally taken orally; however, it is also available as a syrup or injection.

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

Best Clenbuterol Source


If you suffer from asthma or obesity and require clenbuterol for medicinal purposes, we recommend Prestige Pharmaceuticals due to their product efficacy and fast worldwide shipping (2–6 days).

Clenbuterol is legal to purchase in some countries and not in others; thus, it is the responsibility of users to act within the confines of their native law.

Inside Bodybuilding does not condone the use of bronchodilators via illegal means or for cosmetic use.

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Clenbuterol Benefits

  • Fat loss
  • Increased blood flow
  • Enhanced energy
  • Appetite suppression
  • Diuretic
  • No testosterone suppression

Fat Loss

Clenbuterol stimulates the central nervous system (CNS), thus increasing adrenaline output and raising the body’s temperature by as much as 1 degree.

Consequently, in an attempt to maintain homeostasis, the body stimulates the sweat glands to cool itself back down to its previous temperature.

This constant ‘cooling effect’ increases total calorie expenditure, thus spiking a user’s basal metabolic rate.

Thus, we find users will typically burn more calories at rest than usual.

This makes it easier for bodybuilders to eat in a calorie deficit and burn fat indirectly (due to an elevated metabolism).

However, clenbuterol also has direct fat-burning effects (similar to other beta-2 agonists) by accelerating the conversion of triglycerides to free fatty acids.

Increased Blood Flow

Clenbuterol increases adrenaline levels, thus shifting the body into fight or flight mode. Consequently, blood flow improves throughout the body as a survival mechanism.

Thus, we have seen clenbuterol improve muscular endurance, enabling bodybuilders to perform more repetitions than usual in less time.

Note: If a person’s blood pressure or heart rate rises excessively, endurance may suffer on clenbuterol; thus, this benefit is dependent on the person and how they react to clenbuterol.

Pumps can also become bigger due to superior blood circulation to the muscles.

Bigger pumps and increased reps may indirectly help to build new muscle due to stretching of the muscle fascia.

Fascia is a connective tissue that surrounds the muscles; however, if too tight, muscle growth can be inhibited.

As the muscle tries to expand, it effectively pushes against the deep fascia. Therefore, the more flexible this tissue becomes, the greater its potential for muscle hypertrophy.

Bigger pumps from clenbuterol will aid in helping your fascia become more supple, reducing such friction.

Users also report accelerated recovery after workouts and requiring less sleep than usual.

Note: When a person remains in fight or flight mode for an extended period of time, cortisol levels can rise excessively, with vasoconstriction occurring. This impairs blood flow and increases fatigue, which may occur in the latter stages of a clenbuterol cycle following the initial increase in blood flow.

Enhanced Energy

Pre-workouts are popular due to stimulants being present in their formulas, such as caffeine, which gives users intense workouts.

Stimulants arouse the central nervous system, causing the body to release more adrenaline and providing a substantial burst of energy.

Clenbuterol is a powerful stimulant, more so than any standard pre-workout; thus, energy levels will go through the roof.

However, what goes up must come down. Thus, we find users commonly experiencing a crash with low energy after this initial effect wears off, consequently creating a dependence on clenbuterol.

High energy levels of clenbuterol can also (indirectly) help to burn more fat due to workouts becoming more intense. For example, you may perform HIIT on a stationary bike for 15 minutes; however, on clenbuterol, you may be able to comfortably extend this to 20+ minutes.

Appetite Suppression

Clenbuterol has a stimulating effect on beta 2-angrenergic receptors, which can affect satiety levels in humans.

Consequently, our patients have reported not feeling as hungry throughout the day, despite burning more calories.

This effect can indirectly assist with further fat loss due to users being less likely to cave in and binge-eat their favorite high-calorie foods.

This is very beneficial to someone who struggles to ‘diet’, as users will naturally feel fuller for longer periods on clenbuterol, causing them to naturally eat smaller portions.


Clenbuterol doesn’t just burn fat; it also flushes out extracellular water. This can result in a person looking visibly leaner and having increased muscle tone.

We attribute clenbuterol’s diuretic effects to the amount of sweating that occurs.

Therefore, it is important to drink adequate levels of water when taking clen, as you lose sodium through your sweat, which can lead to dehydration and muscle cramps.

Any water lost from taking clenbuterol will return post-cycle, making this diuretic effect temporary.

No Testosterone Suppression

One of the biggest drawbacks we see with anabolic steroids is the shutting down of natural testosterone production.

Typically, after a steroid cycle, it can take several weeks or months for endogenous testosterone to return to normal levels.

However, clenbuterol (unlike anabolic steroids) does not compromise your testosterone. Thus, no PCT is needed, and you don’t need to worry about losing your results.

Legal Clenbuterol Alternative

clenbuterol rating

Clenbutrol is our #1-rated legal clenbuterol product. It replicates the fat-burning and thermogenic effects of clenbuterol, but without any unwanted side effects.

It is FDA-approved and can be purchased online without a prescription.

Clenbutrol is best suited for men or women who want to reduce their body fat percentage while simultaneously increasing muscle tone and endurance.

Clenbuterol Side Effects

  • Increased heart rate (palpitations)
  • Anxiety (shakes)
  • Insomnia

Increased Heart Rate

Clenbuterol arouses the sympathetic nervous system, causing users’ resting heart rate to become excessively elevated.

Dr. Thomas O’Connor also has anecdotal evidence of clenbuterol contributing to heart rates of 180 beats per minute.

We once had a patient experience chronic atrial fibrillation following clenbuterol use (2), a form of irregular heartbeat caused by permanent cardiac scarring.

Thus, clenbuterol is an especially dangerous drug for anyone with existing heart issues or high blood pressure.


Anxiety is a common side effect of taking clenbuterol due to its tendency to shift a person into fight or flight mode. Excessive arousal of the central nervous system may cause a person to perceive everyday situations as threats, negatively affecting their mental health.

A racing heart and palpitations may also trigger anxiety, as users may think they are having a heart attack.

Taking a sedative may help to calm the central nervous system and reduce anxiety levels. However, we have seen this counteract the thermogenic effect of clenbuterol, thus negatively affecting fat loss due to less adrenaline and heat production.

High levels of CNS stimulation are linked to depression due to the subsequent ‘come down’ effect. This is due to clenbuterol initially boosting dopamine levels in the brain (3); for them to drop later as a person builds tolerance or comes off the drug.

Shaking is also common when taking clenbuterol due to its greater adrenaline output. In our experience, this side effect mainly affects the hands.


Insomnia is common among clenbuterol users due to an overly active nervous system, causing hyperactivity (4).

Some bodybuilders suggest taking clenbuterol earlier in the day to improve the chances of falling asleep at night. However, clenbuterol has a very long half-life of 35 hours (5). Thus, we have found this protocol to be ineffective, with high amounts of clenbuterol still peaking in the bloodstream.

It is worth noting that sleep deprivation may elevate cortisol levels, further increasing blood pressure and inhibiting fat burning.

Clenbuterol Dosage

A person’s dosage will depend on what they are using clenbuterol for.

For example, an asthmatic may take two 20-mcg pills per day.

Patients suffering more severely from respiratory issues may take four 20-mcg pills per day.

However, bodybuilders or anyone taking clenbuterol for weight loss purposes may take 6–8 pills per day (120–160 mcg). Such dosages are well beyond the therapeutic range used in medicine; therefore, more severe side effects are to be expected.

People respond to potent stimulants differently; thus, the dosage should be tailored to how sensitive a person is to the drug.

Unlike with anabolic steroids, the dosage of clenbuterol is the same for men and women. This is due to it affecting the CNS rather than working on a hormonal level (where women have significantly less testosterone and thus need smaller doses of steroids to obtain the same level of results).

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Clenbuterol Cycle

The following cycle is taken by men and women who want maximum fat loss and high levels of muscle definition.

clenbuterol cycle

We find users typically build a tolerance to clenbuterol quickly; thus, to prolong its positive effects, users can start on a lower dosage and increase it slowly every third day.

A person should only continue increasing the dosage until they reach the maximum amount with which they are comfortable with the side effects. We have had patients complete a 30-day clenbuterol cycle, comfortably reaching a peak dose of 120 mcg. However, we have also had patients report severe side effects on 80 mcg/day (and thus have to cut their cycle short).

The reason why clenbuterol cycles typically do not last beyond 4-6 weeks is due to beta-receptor downregulation.

Thus, clenbuterol’s positive effects can only be experienced for a limited time until the body successfully regulates its temperature back to normal, causing fat burning to come to a halt.

This is also why some users choose to cycle clenbuterol for 2 weeks on, followed by 2 weeks off, or 2 days on and 2 days off.

2 Week On/Off Clenbuterol Cycle

As previously mentioned, a short clenbuterol cycle can be utilized to prevent the body from building up a tolerance to the drug, ensuring further fat loss in future cycles.

We have found that a 2-week cycle can also reduce cardiovascular strain, among other side effects.

In one journal, a healthy 25-year-old man was rushed to the ER after taking 20 mcg of clenbuterol (6). His heart rate reached 140 beats per minute while also displaying labile blood pressure.

He experienced palpitations, nausea, chest pain, sweating, and anxiety.

Interestingly, he had been taking the same dose for the last 3 weeks with no adverse effects. This is a prime example of how a 2-week cycle can be more optimal for sensitive users.

A 2-week cycle will often start in the 20–40 mcg range, with the dose increasing every 1 or 2 days until a maximum dose is achieved (usually 100 mcg–140 mcg).

Users will then have 2 weeks of rest before cycling clenbuterol again. However, the second cycle begins with the maximum dose from the first cycle. Thus, if the first cycle finished at 100 mcg per day, this would be taken for the entire 2 weeks in the second cycle.

Every follow-up cycle from this point on should then start at the maximum dose to continue making progress.

Clenbuterol and Winstrol Cycle

For Men

clenbuterol winstrol cycle

Winstrol is an anabolic steroid often utilized during cutting cycles to enhance fat loss and lean muscle mass.

The addition of winstrol will have a more anabolic effect than taking clenbuterol alone. Thus, a person will build muscle and burn fat simultaneously on this stack, as opposed to predominantly burning fat with clenbuterol.

The side effects of winstrol are much different from those of clenbuterol. Winstrol is an oral compound like Clen; however, it is highly hepatotoxic. Our liver function tests often show high ALT/AST enzymes in winstrol users, indicating significant strain on the liver.

LDL cholesterol levels will also rise, causing a large spike in blood pressure. Hair loss, prostate enlargement, and acne are other possible androgenic side effects we see due to high DHT levels.

Winstrol will also cause endogenous testosterone production to shut down, taking several months for levels to recover back to normal (hence why bodybuilders opt for post-cycle therapy).

For Women

Winstrol is generally not a recommended steroid for women, due to the high chances of virilization occurring. Such masculine effects, however, may be kept at bay by adopting a low dosage (as shown below).

clenbuterol winstrol cycle for women

There is generally no need to utilize this cycle (as a female) if the primary goal is fat loss. We find that this can be achieved solely by dieting and taking clenbuterol. However, if more muscle tone and size are required, some women may run these two compounds together.

Clenbuterol and Anavar Cycle

For Men

clenbuterol anavar cycle for men

Anavar (oxandrolone) is regarded as a cutting steroid due to its potent effects on fat loss.

Anavar also builds lean muscle and strength, making it ideal for users wanting to get bigger and stronger.

We regard Anavar as slightly less powerful than Winstrol in terms of results, yet a lot more side effect-friendly. Anavar is an FDA-approved steroid in medicine and is thus generally regarded as safe by the bodybuilding community.

For Women

clenbuterol anavar cycle for women

Anavar, unlike Winstrol, is a lot more suitable for women due to the low incidence of masculinization.

A clenbuterol and anavar cycle is taken by women wanting to look lean and strong as opposed to slim.

Thus, female celebrities are likely to take clenbuterol alone, whereas athletes or serious weightlifters may add anavar.

Clenbuterol and Cytomel (T3) Cycle

Clenbuterol can also be stacked with Cytomel (T3) to enhance fat burning. Cytomel is a prescription medication for hypothyroidism (an underactive thyroid).

Simply put, the higher a person’s T3 levels are, the greater the rate of lipolysis (fat burning) in the body.

This stack is considered the ultimate fat-burning duo among bodybuilders looking to get ripped before a competition; however, it is not free from harsh side effects.

Users often take 25–75 mcg of Cytomel per day for 6–8 weeks.

50 mcg is the standard dose for intermediate bodybuilders.

However, bodybuilders will often stack Cytomel with testosterone or another anabolic steroid due to Cytomel’s catabolic effects on muscle tissue.

Clenbuterol Results (Before and After Pictures)

clenbuterol before and after

The user (above) cycled clenbuterol for 2 weeks, starting with a 20 mcg dose and slowly increasing up to 80 mcg/day.

This was the user’s first clenbuterol cycle, hence the impressive results.

We see a person’s results on clen often determined by the dosage, length of cycle, genetics, diet, and workout routines.

For maximum fat loss, users should eat within a 500-calorie deficit. Clenbuterol’s metabolic effects will effectively be blunted if a person eats in a calorie surplus.

In our experience, men and women can expect to lose 10–15 pounds from a 4-week cycle of clenbuterol.

Similarly to steroids, the more clenbuterol cycles a person performs, the less fat loss they will experience with each one.

A PCT isn’t needed with any of these products, as they do not suppress users’ natural testosterone production. Women can also take these legal steroid alternatives, as they do not cause virilization symptoms, unlike anabolic-androgenic steroids.

In short, clenbutrol is a much safer version of clenbuterol and will not cause an athlete to fail a drug test.

Clenbutrol Reviews (Before and After Pictures)

clenbuterol results

Balwinder’s results from taking clenbutrol for 5 weeks

legal clenbuterol before and after

John Miller’s results from taking CB’s cutting stack (including clenbutrol) for 8 weeks

clenbuterol review

Kim lost 8 pounds after taking clenbutrol, anvarol, and winsol for 1 month. She lost 2 inches on her waist and 2.5 inches on her hips.


Clenbuterol vs Albuterol

Albuterol sulfate (also referred to as salbutamol) is a beta-2 adrenergic agonist, like clenbuterol.

The main difference, however, is that albuterol is FDA-approved and an available prescription drug for the treatment of asthma.

Albuterol also burns fat through the process of thermogenesis, via the stimulation of the CNS. Thus, the benefits and side effects of albuterol are largely the same as those of clenbuterol.

However, albuterol is not as potent as clenbuterol, being regarded as a ‘cleaner stimulant’.

Consequently, albuterol’s side effects are more tolerable, making it more cardiovascular-friendly.

However, the results on albuterol are less noticeable in our experience, with fat loss and energy levels being more noticeable on clenbuterol.

Albuterol also has a shorter half-life than clenbuterol, being 4-6 hours, thus requiring more frequent doses (3–4 times per day).

Albuterol is administered via the same method as clenbuterol (in pill form). However, in medicine, albuterol is prescribed in the form of an emergency inhaler.

Is Clenbuterol Legal?

Yes, clenbuterol is technically legal in the US and other countries, as it is not listed in the Controlled Substances Act.

However, it is not approved by the FDA, so users should be aware of its potentially damaging side effects.

Clenbuterol is also on the WADA banned list of substances; thus, athletes can still fail a drug test and be suspended (if found lingering in their system).

Is Clenbuterol Safe?

The FDA has not approved clenbuterol for human use, which is an indicator of its toxic nature.

The Peking Union Medical College in Beijing, China, concluded that clenbuterol only had mild effects when given to rabbits (7).

However, when higher doses were administered, their heart rates increased drastically, inducing severe hypotension.

Thus, research suggests that clenbuterol’s safety may be dose-dependent (8). Anecdotally, we have also found higher dosages to be unsafe in regard to cardiotoxicity.

Note: Men and women with existing heart issues are at great risk when taking clenbuterol (irrespective of the dose). Also, if users are stacking clenbuterol with anabolic steroids, cardiac-related side effects will be exacerbated (9).

Is Weight Loss From Clenbuterol Permanent?

Yes, all results from clenbuterol are permanent and will not be reversed post-cycle.

However, a person must continue training and eating correctly if they want to maintain their results.

Note: Water loss is the only temporary effect; therefore, users may regain a small amount of fluid when they finish their cycle.

Does Clenbuterol Work?

Yes, clenbuterol not only works but is arguably the most potent fat burner in the world today.

However, it is bought on the black market, where supplements are often tainted (10); thus, it is difficult to know if you are getting 100% real, authentic clenbuterol.

clenbuterol bottle
As a general rule, if you are not experiencing fat loss or feeling your body temperature rise, it is not clenbuterol.

However, it is worth noting that clenbuterol is not a compound typically counterfeited (possibly due to its low market price), although it still occurs.

Can You Drink Alcohol With Clenbuterol?

Alcohol consumption is usually a bad idea when taking oral anabolic steroids due to their hepatotoxic nature. However, clenbuterol is not an anabolic steroid but instead a bronchodilator, and it is not liver toxic.

However, the main concerns we see with clenbuterol are excessive rises in heart rate, increased blood pressure, and dehydration. Alcohol will exacerbate all three of these side effects due to increased cortisol production, so it should be avoided.

Also, alcohol will blunt the fat-burning effects of clenbuterol, especially in stubborn areas, due to cortisol being a fat-storing hormone.

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