This drug belongs to the group of drugs used in hormone therapy, belongs to the group of hormone antagonists, enzyme inhibitors.
The effect of use is due to the properties of its main active ingredient – letrozole. Letrozole is a highly specific non-steroidal inhibitor of aromatase activity, which also has the property of inhibiting estrogen biosynthesis. Thus, letrozole produces an antitumor effect in cases where the tumor is estrogen-dependent.
In postmenopausal women, estrogens are synthesized through the enzyme aromatase. This enzyme causes the conversion of androgens, to estrone and estradiol. As a consequence, letrozole ability to inhibit aromatase can suppress biosynthesis of estrogen hormone in tumor tissues as well as in peripheral tissues.
Letrozole steroid drug description
Letrozole is a nonsteroidal aromatase inhibitor (estrogen biosynthesis inhibitor) anti-tumor drug. In cases where tumor tissue growth depends on the presence of estrogen, elimination of estrogen-mediated stimulating effects is a prerequisite for suppressing tumor growth. In postmenopausal women, estrogens are formed primarily by the aromatase enzyme, which converts androgens that are synthesized in the adrenal glands (primarily androstenedione and testosterone) into estrone (E1) and estradiol (E2). Therefore, by specific inhibition of the aromatase enzyme, suppression of estrogen biosynthesis in peripheral tissues and in tumor tissue can be achieved.
Letrozole inhibits aromatase by competitive binding to a subunit of this enzyme, the cytochrome P450 heme, which leads to a decrease in estrogen biosynthesis in all tissues. In healthy postmenopausal women, a single dose of letrozole, which is 0.1 mg, 0.5 mg and 2.5 mg, reduces serum estrone and estradiol levels (compared to baseline) by 75-78% and 78%, respectively . The maximum reduction is achieved after 48-78 hours.
In women with advanced postmenopausal breast cancer, daily use of letrozole at a dose of 0.1 mg to 5 mg reduces plasma levels of estradiol, estrone, and estrone sulfate by 75 to 95% of baseline levels. When the drug is used at a dose of 0.5 mg or more, in many cases estrone and estrone sulfate concentrations are below the sensitivity limit of the method used to determine the hormones. This indicates that a more pronounced inhibition of estrogen synthesis is achieved with these doses of the drug. Estrogen suppression was maintained throughout treatment in all patients.
Letrozole is a highly specific inhibitor of aromatase activity. Disruption of steroid hormone synthesis in the adrenal glands was not detected. In postmenopausal patients treated with letrozole at a daily dose of 0.1-5 mg, no clinically significant changes in plasma concentrations of cortisol, aldosterone, 11-deoxycortisol, 17-hydroxyprogesterone, ACTH, and renin activity were found. Performing an ACTH stimulation test after 6 and 12 weeks of letrozole therapy at a daily dose of 0.1 mg 0.25 mg 0.5 mg 1 mg 2.5 mg and 5 mg showed no detectable decrease in aldosterone or cortisol synthesis. Thus, there is no need to prescribe glucocorticoids and mineralocorticoids.
In healthy postmenopausal women, no changes in plasma androgen (androstenedione and testosterone) concentrations were detected after a single use of letrozole at doses of 0.1 mg, 0.5 mg and 2.5 mg. In postmenopausal patients who received letrozole in a daily dose of 0.1 mg to 5 mg, no changes in plasma androstenedione levels were observed either. All this indicates that blockade of estrogen biosynthesis does not lead to accumulation of androgens, which are precursors of estrogens. In patients receiving letrozole, no changes in plasma concentrations of luteinizing and follicle-stimulating hormones were observed, and no changes in thyroid function were noted, assessed by the levels of thyrotropic hormone T 4 and T 3.
Letrozole fat burner, weight support
Achieving and maintaining a healthy body weight is the first thing you can do for your overall health. Being overweight and having too much body fat is associated with an increased risk of developing certain diseases, including certain types of cancer, type 2 diabetes, high blood pressure and heart disease. Post-menopausal women who are overweight or obese are at higher risk of developing breast cancer. According to research, significant weight gain during or after breast cancer treatment can increase both the risk of breast cancer recurrence and the risk of developing other types of cancer.
BMI is a measure of body weight including height. It is one way to measure body weight. BMI does not give an indication of the ratio of muscle mass to excess body fat in the body, so it cannot be the only measure of overall health. Nevertheless, this index can be a useful tool for assessing health and disease risk. Most normal adult BMI ranges from 18.5 to 24.9.
Controlling weight gain after diagnosis and treatment
People often gain weight after breast cancer diagnosis and treatment. People can gain weight during or after treatment for many reasons. Among them:
Consuming too many calories with food;
Lack of physical activity;
Early onset of menopause;
depression (intense feelings of sadness) and anxiety (intense feelings of anxiety or fear);
unusually strong feelings of hunger due to taking steroids;
Eating food to calm or cope with emotions;
Eating more food than usual because of side effects of the treatment, such as fatigue (feeling unusually tired) or nausea (feeling sick and wanting to vomit).
If you have gained weight, it can be difficult to lose it. Therefore, it is important to try to maintain a normal weight during treatment. Follow the guidelines below to help prevent weight gain. In consultation with your clinical nutritionist, work toward your weight goals.
Make a balanced diet. Check out the helpful tips in the Healthy Eating Plate section.
Control your portion sizes.
Always put food on your plate so you know how much you have eaten. Do not eat out of a container or bag. Don’t eat in front of the TV, at the computer (e.g., when checking mail or watching a movie), or while on the phone. Drink 8 cups (8 ounces [240 ml]) of fluids each day. Give preference to water and other beverages that do not contain calories, such as mineral water. Do not drink more than 1 cup of fruit juice per day. It is better to eat whole fruit than to drink juice. You do not need to change your entire diet at once. You can set yourself 1 or 2 goals each week. If you fail, you can learn from your mistakes. Small changes over time lead to noticeable results.
Letrozole is an excellent drug for weight loss
Letrozole is a drug used to treat breast cancer. It is also sometimes prescribed to help women lose weight. Letrozole works by blocking the action of estrogen, which can help reduce appetite and promote weight loss. Although Letrozole is not approved by the FDA for weight loss, it has been shown to be an effective tool for losing weight.
In a recent study, it was found that Letrozole can help individuals lose weight. The study showed that Letrozole helps to increase the amount of energy used by the body, which leads to weight loss. Letrozole is a drug that is used to treat breast cancer, and has been shown to be effective in helping people lose weight. In addition to weight loss, Letrozole has also been shown to improve lipid levels and reduce the risk of heart disease.
In the past, most doctors would have recommended a patient to undergo surgery in order to lose weight. However, with the development of new drugs such as letrozole, this is no longer necessary in many cases. Letrozole has been shown to be an extremely effective weight loss drug, with very few side effects. Patients who take letrozole often see dramatic results, losing large amounts of weight in a relatively short period of time.