Letrozole – use in sports and bodybuilding

Letrozole’s mechanism of action is related to the blockade of aromatase, a special enzyme responsible for the conversion of testosterone into estrogen. The drug was created for the treatment of estrogen-dependent tumors in women, but the popularization of bodybuilding has opened up new opportunities: Letrozole for male athletes is prescribed to eliminate the dangerous side effect of steroids – feminization.

Properties of letrozole


  • Prevents gynecomastia.
  • Increases the content of biologically active substances with anabolic effects.
  • Effective for drying through hormonal regulation of subcutaneous fat thickness.
  • Stabilizes blood pressure.
  • Normalizes sexual function.
  • It can be used to eliminate feminization phenomena that have already occurred.
  • Long half-life: Can be taken once every 2-3 days.
  • Paying price.
  • Low toxicity.
Properties of letrozole

Properties of letrozole

Despite the relatively low toxicity, experts strongly recommend undergoing a general medical examination before starting the drug.


  • Not suitable for all steroids: not effective when taken together with Boldenone and Halotestin.
  • Risk of excessive estrogen suppression with associated side effects.

Side effects

The use of the drug can cause the following side effects:

  • Aggravation of muscle mass gains.
  • Reduced power.
  • Osteoporosis.
  • Increased risk of arteriosclerosis.
  • Bone and joint pain.
  • Weakness, fatigue.
  • indigestion.
  • Hair loss.
  • Mental disorders: depression, anxiety, sleep disorders, irritability, memory problems.

Almost all clinically significant side effects occur against the background of an incorrectly selected dose.

It is important!

Letrozole in sports works best with regular monitoring of estrogen levels in the blood.

Letrozole in bodybuilding

Letrozole in bodybuilding

Letrozole in bodybuilding

Reception of letrozole in bodybuilding and not only should be started long before the moment when the level of estrogen exceeds the critical value and leads to swelling, severe inhibition of potency, enlargement of the nipples and peripapillary zone. If such a situation has already occurred, it is important to start treatment as soon as possible: the elimination of symptoms requires daily administration of the drug in a daily dose of 1 tablet. (0.0025g).

Ideally, letrozole should be taken prophylactically. To increase testosterone and maintain its level, the drug is prescribed from the 7th to the 10th day of the AAS cycle in a dose of only 1/5 tablet (0.0005 g) every other day. This approach reduces the risk of side effects and increases the effectiveness of training.

Immediately after the completion of the AAS course, letrozole is not canceled; it should be taken for another 2-3 weeks. If possible, the dose of the drug should be selected individually and based on the level of estrogen or, in extreme cases, subjective feelings and general well-being.

Read also about Letrozole Dosage

Knowing how to take letrozole correctly will allow you to achieve maximum bodybuilding results and maintain your health.