Trenbolone Side Effects The Good and Bad

When it comes to building serious amounts of lean hard muscle nothing compares to trenbolone.

Bodybuilders love it, because trens anabolic and androgenic potency is unequaled. Its their steroid of choice in the run up to a competition because its highly effective at accelerating  gains. 

According to the anabolic androgenic ratings scale Trenbolone has a 500 rating for both anabolic and androgenic effects.

Now compare this with another powerful steroid, testosterone.

Test has an anabolic and androgenic rating of only 100 making trenbolone five times more powerful. 

No wonder bodybuilders call tren the 'King of Steroids'.

Trenbolone was originally designed as a veterinary drug to beef up cattle before they were taken to the slaughter house.

The compound has never been officially recommended for human use.

So, the pioneering bodybuilders who first tried out tren were the ultimate guinea pigs.

"Trens anabolic and androgenic rating of 500 makes it the most powerful compound around."

Although it produces amazing lean hard muscle growth and strength hardness, it has many harsh sides and needs to be handled with care and respect.

A Trenbolone only cycle is never recommended as it will shut you down. It should always be stacked with another compound such as testosterone cyp.

OK, lets dig further in to the good and bad side effects of this beast.

Trenbolone Steroid Profile

Trenbolone is classed as a 19 Nortestosterone AAS compound.

The number 19 refers to the missing carbon at the 19th position of testosterones molecule structure.

In fact, Trenbolone is an altered derivative of the nandrolone hormone Decanoate (Deca Durabolin). The key difference is tren's additional double bond at the carbon position of 9 and 11, giving  the compound unique and powerful traits.

The double bond not only suppresses aromatization it makes tren more effective at binding and activating the androgen receptors. This is key because the growth of new muscle fibers is dependent on the activation of these androgen receptors.

Trenbolone Acetate vs Trenbolone Enanthate

The main difference between tren ace v tren e is the ester length.

Acetate has a shorter ester than enanthate. There’s also a third ester called trenbolone cyclohexylmethylcarbonate (Parabolan) which has the longest ester of the three.

As with all injectable anabolic androgenic steroids the ester doesn't change the drug, it only affects the rate at which it is released into the body. 

How Esters Effect Results

Tren Enanthate’s longer ester means its released at a slower rate and stays in the body for longer. In contrast, Tren Ace shorter is absorbed at a faster rate. Shorter esters also have a higher concentration per milligram.

Trenbolone acetate side effects can be felt quickly. The speed of release has an effect on how the steroid is absorbed. Some argue that faster acting esters enable more of the drug to be absorbed before the body’s de-esterification takes effect.

Which Ester Should You Choose?

Two tren esters gives you a choice of how quickly you want to see results.

However, there are a few things to consider before choosing an injectable trenbolone ester.

The pros of using a longer ester such as tren enanthate is that you don’t have to inject that often. Every 5 to 7 days is the norm. Also, trenbolone e side effects don’t hit you as fast due to the slow release.

Pros and Cons of Trenbolone Enanthate


  • Fewer injections
  • Longer lasting results
  • Cheaper than acetate 


  • Side effects last longer 
  • Gains are slower
  • Low availability

A longer ester stays in your body for longer meaning , therefore trenbolone enanthate side effects take longer to subside.

Pros and Cons of Trenbolone Acetate


  • Experience Gains faster 
  • Side effects wear off faster
  • More available 


  • More injections
  • More expensive 

A big advantage with trenbolone ace is the faster gains you'll experience with a shorter ester.

Also, tren ace  leaves the body at a faster rate so, any harsh side effects are short lived.

The biggest downside of tren ace are the frequency of the injections. Because it peaks so fast you'll need to inject every second day.

However, your choice will be influenced how you respond to the tren side effects. If you react badly, its better to use a shorter ester as the effects wear off quickly.

''Your choice of ester depends on your tolerance to Tren's side effects''.

In contrast, tren e side effects linger for longer.

If you haven’t used trenbolone before and you don’t mind frequent injections, then trenbolone ace would be better choice. With more experience you can progress to a longer ester.

Trenbolone’s Good and Bad Side Effects

Trenbolone is the most powerful fast acting hardcore anabolic androgenic injectable steroid you can get your hands on.

When on Tren expect impressive lean hard gains. But there are major downsides. Tren 75 side effects are harsh and you need to be aware and prepared for them before you even think about touching this compound.

There are also a few warnings you need to heed about trenbolone:

  1. Never use trenbolone as your first cycle.
  2. Never run a tren only cycle - always stack with another compound.

Tren’s Good Side 

When on Tren expect impressive lean hard gains.

But there are major downsides. Tren 75 side effects are harsh and you need to be aware and prepared for them before you even think about touching this compound.

  • Increases muscle strength and hardness
  • Increases vascularity
  • Efficient nutritional partitioning
  • No water retention
  • Gives you skin splitting pumps
  • Gets you cut​

Tren’s Bad Side 

Now for the bad side effects:

Estrogenic and Progesterone Related Side Effects

Because it can’t be aromatized trenbolone is not estrogenic.

This makes it a unique mass building hormone because it doesn’t cause water retention.

However, a lack of aromatization doesn’t give you a ‘get out jail card’ when it comes to other estrogenic side effects such as gynecomastia. If you’re susceptible to gynecomastia you have a higher risk of developing man boobs with tren.

Its believed trenbolone’s ability to increase prolactin levels, a protein hormone that stimulates milk production, is the main culprit.

However, William Llewellyn, author of the authoritative reference guide on steroids ‘Anabolics’, conducted numerous studies into progesterone related gyno as as result of using Tren. He states..

However, William Llewellyn, author of the authoritative reference guide on steroids ‘Anabolics’, conducted numerous studies into progesterone related gyno as as result of using Tren. He states..

“this steroid displays significant binding affinity for the progesterone receptor (slightly stronger than progesterone itself ).The side effects associated with progesterone are similar to those of estrogen, including negative feedback inhibition of testosterone production and enhanced rate of fat storage.

Progestins also augment the stimulatory effect of estrogens on mammary tissue growth. There appears to be a strong synergy between these two hormones, such that gynecomastia might even occur with the help of progestins, without excessive estrogen levels.”


David is saying is that Trenbolone is strongly progestin (a female hormone) in nature which can mean guys who are prone to gyno have a higher risk of developing male breasts.

Llewellyn also points out the risk increases when trenbolone is stacked alongside other aromatizing steroids. Its very common among bodybuilders, to stack tren with testosterone, which has a strong aromatizing nature.

If you’re running a Tren Ace and Test cycle it's highly recommended to take an aromatizing inhibitor such as Aromasin to combat the gyno issues.

Also, using any type of nandrolone steroid will increase the levels of prolactin. For this reason, many bodybuilders use a prolactin inhibitor such as Dostinex (Cabergoline).

Androgenic Side Effects

Trenbolone scores a 500 androgenic rating , which means you can definitely expect androgenic related side effects.

The most common are oily skin, acne, and hair growth. Women can experience a deepening voice, facial hair growth, menstrual irregularities and enlarged clitoris.

Tren can also accelerate hair loss in men who are pre-disposed to male pattern baldness.

Cardiovascular System

Physical Performance and Endurance

Although a powerful muscle builder, trenbolone can actually decrease cardio performance and endurance. For this reason, athletes rarely touch it.

Bodybuilders love it, but to counteract the drop in cardio performance they’ll take a performance enhancer such as Cardarine(GW 501516.

Effects on physical performance are dependent on dosage levels.

High doses of Tren may increase levels of prostaglandin F2alpha, a naturally occurring compound that constricts the pulmonary capacity (the amount of oxygen you can breathe in) of the lungs.

This of course makes cardio training more difficult due to the lungs limited capacity to take in more oxygen.

Most users don’t seem to be effected by this and the symptoms disappear when they stop using Tren.

However, asthmatics should approach tren with caution, or even better avoid it altogether. Its for these reasons that trenbolone is considered a visual-enhancing drug rather than a performance enhancing one.

Cholesterol Levels

As with all AAS drugs, tren can have harmful effects on cholesterol.

The steroid has a tendency to lower HDL, your good cholesterol, while elevating LDL, your bad cholesterol. With a higher LDL and lower HDL ratio you're at greater risk of developing arteriosclerosis.

The harmful effects on blood lipid levels may not be as high as oral steroids, however trenbolone effects are far more pronounced when compared with other injectable anabolic steroids.

There are a number of ways to minimize the risks:

  • Do regular cardio workouts
  • Avoid saturated fats and processed foods
  • Consume more healthy fats such as omega 3 and fish oil

For ultimate protection take a quality cardiovascular support supplement such as Lipid Stabil.

High Blood Pressure (Hypertension)

There may be a slight risk of elevated blood pressure when using trenbolone. This shouldn’t be a concern if you’re healthy and blood pressure is normal.

If you have a history of high blood pressure you should avoid taking Tren or at least seek medical advice before using it.

Testosterone Suppression

All anabolic steroid compounds suppress natural testosterone production, although the amount varies depending on the steroid used.

In Trens case, testosterone suppression is very high and rapid. This can seem counter-intuitive, as you would expect a compound that doesn't convert to estrogen wouldn't have testosterone suppressing properties.

However, plenty of anecdotal evidence suggests Trenbolones progestin nature is a makes it an aggressive testosterone suppressor. For this reason, bodybuilders stack trenbolone with testosterone to prevent levels dropping too low.

Natural testosterone levels should gradually return to normal once you stop using trenbolone however, levels will be very low, especially if you're taking high doses.

For example, very low levels of testosterone elevate the negative effects of cortisol.

Cortisol is catabolic in nature, so its important to control it, otherwise it will eat away at your gains.

''Make sure your testosterone levels don't drop too low as this leads to a whole host of problems.''

For this reason, a full PCT is recommended after a test and tren cycle.

Long term abuse of trenbolone can lead to prolonged hypogonadotrophic hypogonadism (HH). In men this can lower the release of Luteinizing Hormone (LH), which is needed for testosterone production. HH can also lead to loss of muscle mass and disrupt women's menstrual cycle.

Furthermore, William Llewellyn, a researcher in the field of human performance enhancement, recently published interesting findings on trenbolones effects on testosterone:

“Trenbolone was determined to be approximately three times stronger at suppressing gonadotropins than testosterone on a milligram for milligram basis.”

BTW, gonadotropins are hormones produced in the pituitary gland and have an important role in promoting the production of sex hormones and sperm.

Tren Cough

Coughing is a common side effect with injectable oil based steroids, but it can get really bad with trenbolone.

So bad, many bodybuilders refer to it as ‘tren cough’.

Coughing can start soon after injection and its caused by a small amount of oil leaking into the vein or capillary that the needle passes through.

As the oil enters the bloodstream the body treats it as foreign matter that needs to be expelled. It does this by transporting the oil to the lungs were it is coughed out. This is the reason why coughing is a common side effect of oil based injectable compounds

The intensity of the cough depends on the individual and how their body reacts. Also, higher dosages  intensify the side effects. The coughing can be mild to very intense, which can be a frightening if you're new to trenbolone.

Bodybuilders badly effected by ‘tren cough’ often stack trenbolone with Cardarine (GW-501516) which can help reduce the coughing symptoms.


Injectable steroids are considered less toxic than c17 alpha alkylated oral steroids.

There’s also little evidence to suggest trenbolone leads  to liver damage when taken within safe dosage levels.

However, tren can stress the liver because the drugs chemical structure is resistant to the organs initial metabolic breakdown. For this reason, a liver support supplement would be recommended before and during a trenbolone stack cycle.

Rumors about trenbolone causing kidney damage is unfounded as there's no scientific evidence to supports this.

The rumors are spread by inexperienced steroid getting alarmed at seeing their urine turn a very dark color. In fact, this is nothing to worry about because trens oxidative nature turns your piss an orange brown color.


Most steroids can disrupt normal sleeping patterns, but it seems tren affects more people than any other steroid, hence the reason this side effect is often called 'trensomnia'.

There's no clear scientific evidence explaining why although, the compounds stimulating effect on the body’s central nervous system and metabolism is often blamed.

Sufferers can reduce symptoms by lowering the dosage and taking sleeping aids such as melatonin.

Excessive Sweating 

Excessive sweating, particular at night, is another unique side effect of trenbolone.

Many attribute this to trens superior nutrition-partitioning properties. Although all steroids do this, tren takes it to a higher level. Nutrition-partitioning increases the body’s metabolism and core temperature. As the core temperature rises the body perspires to cool you down.

Sweating can happen at any time during the day, but many trenbolone users experience excessive sweating during the night. These nights sweats are more of an inconvenience than a danger to your health, as it spoils a good nights sleep.

However, dehydration can be an issue with high levels of water loss. For this reason drink plenty of water when taking Trenbolone.

Other Side Effects

For some people trenbolone can effect them emotionally. For example, many users feel more aggressive or they have a shorter fuse. They’re easily triggered when someone or something upsets them.

Others can feel grumpy, tired or socially more introverted during a trenbolone cycle.

Maintaining Gains

Steroids are a roller coaster ride. You're making massive gains when you're on them and losing most of those gains when you're off them. This is even more of an issue with trenbolone, because its so anabolic.

To minimize those losses many bodybuilders bridge their cycles with good quality legal steroids. We recommend this.