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Femara
Last reviewed: 23.04.2024
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Femara is an antitumor drug.
[1]
Indications of the femara
It is used to treat such disorders:
- breast cancer (in a common form) in postmenopausal women and previously treated with anti-estrogens (such as tamoxifen);
- the initial phase of breast cancer in women at the postmenopausal stage.
[2]
Pharmacodynamics
The drug is non-steroidal and has an antitumor effect. Femara is a drug that specifically inhibits the activity of the aromatase enzyme. With the help of competitive synthesis with a subunit of the aromatase enzyme, which participates in the binding of estrogens, prevents the stimulating effect of the latter against growth of the tumor. It also helps to suppress its growth independently.
During the treatment of breast cancer in a common form (at the stage of postmenopause), daily intake of letrozole causes a decrease in the values of estrone sulfate, as well as estrone with estradiol inside the blood (by 75-90%). At the same time, there is no change in the rates of androstenedione. Thus, the blockade of the processes of estrogen biosynthesis does not result in the cumulation of androgens, which are precursors of estrogens. In addition, there are no changes in the level of lutropin and FSH, as well as in the thyroid hormones.
The drug has no effect on the binding processes of the steroid hormones located in the adrenal glands, which allows to avoid correction of SCS and mineralocorticosteroids.
Pharmacokinetics
Letrozole at high speed is absorbed from the digestive tract. Bioavailability indicators are 99.9%. Eating food slightly reduces the degree of absorption. Synthesis with blood protein is 60%.
Equilibrium indicators are noted after 3-6 weeks, if you take the medicine in a standard portion every day. The drug undergoes metabolic processes, in which an inactive compound is formed.
Excretion of metabolic products of the substance occurs through the intestine with the kidneys. The half-life is 48 hours.
Use of the femara during pregnancy
It is forbidden to prescribe femara to pregnant women.
Contraindications
The main contraindications:
- the period of breastfeeding (if necessary, drugs should be abandoned breastfeeding);
- the presence of intolerance with respect to the elements of the medicinal product;
- hormonal status, which occurs in women in the reproductive period;
- children and adolescents under the age of 18 years.
[11]
Side effects of the femara
The use of drugs usually causes side effects with a moderate degree of severity. They do not require the cancellation of the reception.
Among the negative reactions are: puffiness, rashes, headaches, vomiting with nausea and a feeling of general weakness. In addition, there are hot flushes, pain in the back and hands with legs. There is also a thinning of the hair, weight gain, vaginal bleeding and anorexia.
Interactions with other drugs
In the case of a combination with tamoxifen in a dose of 20 mg, the value of this drug is reduced by 38%, with no adverse effect on tamoxifen. There is no information on the use of drugs with other antitumour agents.
The probability of a significant interaction of the drug with isoenzyme CYP2C19 is rather low. But to use it in combination with medications, the metabolism of which occurs with the help of isoenzymes of the hemoprotein, you need to be cautious.
Storage conditions
Analogues
The analogues of the drug are the products of Letrotera, letrozole with Letrozol-Teva, and in addition Extrase and Letroz.
Reviews
Femara is included in the category of nonsteroidal drugs that slow down the activity of aromatase (3rd generation), and they, according to existing data, are able to reduce by 98% the estrogen values that are formed with androgen from the androgen in women who are at the postmenopausal stage. Among the drugs from this group, it is the Femara that is most effective.
When using this drug during early supportive treatment, it will be more effective than Tamoxifen (when making comparisons taking into account the frequency of recurrence and the time periods before the onset of metastases). The medication is considered very effective and safe at the same time (especially for women who have a high likelihood of recurrence (in the presence of metastases in the lymph nodes or if the woman previously underwent chemotherapy procedures)). Sometimes the use of the drug can avoid radiation and cytostatic therapy, as well as surgical intervention.
Reviews show that this drug is better tolerated than Tamoxifen. The therapy lasted 4.5-6 years and only some patients developed side effects: myalgia, hot flashes, and also arthritis. In addition, development of anorexia, peripheral edemas, nausea and severe fatigue was observed.
Patients also say that taking drugs that slow the activity of aromatase often causes the development of osteoporosis and increases the likelihood of fractures. Because of this, combination therapies include tools such as Zometa, which is a biophosphonate.
[20]
Attention!
To simplify the perception of information, this instruction for use of the drug "Femara" translated and presented in a special form on the basis of the official instructions for medical use of the drug. Before use read the annotation that came directly to medicines.
Description provided for informational purposes and is not a guide to self-healing. The need for this drug, the purpose of the treatment regimen, methods and dose of the drug is determined solely by the attending physician. Self-medication is dangerous for your health.