Hormonal agents with antiestrogen action are used in oncology for the treatment of hormone-sensitive tumors. In bodybuilding, they are used to suppress the synthesis of female sex hormones with a high intake of androgens.
Other names and classification
The drug is classified as an estrogen antagonist.
Russian name
Tamoxifen
Latin name
Trade names
On sale there is a drug with the following names:
- Nolvadex;
- Istubal;
- Valodex;
- Tamofen.
CAS code
Composition and dosage forms of Tamoxifen
Available in the form of tablets with a dosage of 10 mg of tamoxifen citrate. Some manufacturers increase the concentration of the active substance to 20, 30 or 40 mg. Additional substances give the form of a tablet.
Pharmacological group
Anticancer agent, antiestrogen.
Pharmacological action of Tamoxifen
It is not a steroid, but may exhibit weak estrogen properties. In target organs, it binds competitively to estrogen receptors. These bodies are:
- breast;
- pituitary;
- uterus;
- vaginal tissues.
The antitumor effect is also based on the blocking of estrogen receptors in carcinoma. The drug, after connecting with the active center, does not stimulate DNA synthesis, as it normally does, but inhibits cell division. This inhibits the growth of the tumor and causes its gradual death.
The blocking effect on estrogens persists for several weeks after a single dose.
In women with menstrual irregularities, it can induce ovulation by acting on the hypothalamus and stimulating the hypothalamic releasing factor, which acts on the pituitary gland and causes the release of appropriate hormones.
In men, the use of the substance leads to an increase in the blood of luteinizing and follicle-stimulating hormones, which accelerate the production of spermatozoa. This effect is used in oligospermia. At the same time, the concentration of testosterone in the blood serum increases. This effect is used in bodybuilding to prevent the conversion of androgens into female sex hormones.
The tablet taken orally is well absorbed. The maximum effect develops after 4-7 hours. A constant equilibrium concentration of a substance in the blood is maintained with a 3-4-week regular intake.
Metabolism takes place in the liver. The half-life of the active substance is 7-14 hours, but the terminal metabolites leave the body no earlier than a week later. The bulk is excreted with feces.
Indications for the use of Tamoxifen
The main purpose of the drug is the treatment of oncological diseases:
- mammary cancer;
- carcinoma in situ of the milk duct;
- endometrial cancer;
- ovarian tumors.
It is used to treat breast carcinoma, including in men after castration, in postmenopausal women.
For men, it is used in the treatment of prostate cancer, prostatitis and glandular adenoma. Estrogen receptors have prostate tumors, so the choice of the drug is justified.
In bodybuilding, it is taken for anti-estrogen action and to reduce side effects after taking testosterone preparations.
How to use?
Admission rules are set individually depending on the indications for use.
Before meals or after?
Tablets are taken 1 time in the morning with meals, do not chew and drink plenty of water. You can divide the dosage into 2 doses - in the morning and in the evening.
In bodybuilding
Assign after a course of steroids in combination with aromatase inhibitors, such as Proviron. Tablets are taken orally daily. The first pill is taken a week before the end of the testosterone cycle, and the last one is taken 2 weeks after the end of the male hormones.
Dosage
The required number of tablets is selected individually depending on the indications. The standard dose is 20 mg. But the doctor can adjust the dose and treatment regimen.
In bodybuilding, the dosage is 10-20 mg.
special instructions
During cancer treatment, women should see a doctor regularly. If bleeding or spotting appears from the vagina, then the course is stopped. With caution are treated with mastopathy. In women with bone metastases, it is necessary to periodically determine the concentration of calcium in the blood serum. With the appearance of pronounced deviations from the norm, the drug should be discontinued.
There is a high risk of ovulation and pregnancy, so while taking the medicine, you must use any non-hormonal methods for contraception: a condom, an intrauterine device, spermicides.
In order to timely identify the toxic effect of the drug, it is necessary to control the general blood test, coagulation, calcium levels, cholesterol and triglycerides, liver enzymes. Sometimes it affects the normal functioning of the liver.
During pregnancy and lactation
It is forbidden to use the drug for pregnant and lactating women.
For impaired renal function
It is prescribed with caution in renal pathologies leading to a violation of their function.
Adverse reactions
Undesirable reactions are associated with a direct antiestrogenic effect. In women, there are signs that are characteristic of a lack of sex hormones:
- hot flashes;
- sweating;
- feeling of heat;
- headache;
- vaginal spotting;
- alopecia.
In the presence of metastases in the bones, pain appears in the region of the foci. Nausea, vomiting, abdominal pain and dizziness are rarely observed. With a predisposition, changes in the cornea, cataracts, retinopathy may occur. Action on nervous system leads to the appearance of confusion, depressive disorder, fever.
At the beginning of cancer therapy, there may be a short-term deterioration in the condition and progression of the disease, which resolves within 2 weeks.
Antiestrogens increase the risk of developing thrombophlebitis and thrombosis. Liver enzymes are rarely elevated, and even more rarely severe liver damage occurs.
An estrogen antagonist can cause menstrual irregularities. With prolonged treatment, amenorrhea develops. In some women, there is a change in the structure of the endometrium towards hyperplasia, polyps, fibromas. Occasionally, endometrial cancer has been reported.
In men, the drug can lead to the following reactions:
- baldness;
- decreased erection;
- increased fatigue;
- gynecomastia;
- anorexia.
Other signs may be similar to those of women.
Contraindications
Do not use the drug in the presence of hypersensitivity or intolerance to any component of the drug. Contraindications are:
- kidney disease;
- diabetes;
- thrombophlebitis and thrombophilia;
- pregnancy and lactation;
- childhood.
Overdose
There are no data on cases of acute overdose. It is assumed that if the recommended doses are exceeded for a long time, the negative effects and side effects of the drug may increase. There is no specific antidote. Therefore, treatment is carried out depending on the symptoms that appear.
The composition of Tamoxifen includes 15.2; 30.4 or 45.6 mg tamoxifen citrate , which, respectively, is equivalent to 10, 20 or 30 mg of tamoxifen.
Tablets are packaged in blisters, containers or polyethylene bottles of 10, 20, 30, 40, 50, 60, 90, 100, 120, 150 or 300 pieces.
Release form
Tablets.
pharmachologic effect
It has antiestrogenic and antitumor properties.
Pharmacodynamics and pharmacokinetics
Tamoxifen is non-steroidal anticancer antiestrogen drug characterized by the ability to competitively inhibit peripheral estrogen receptors in target organs and tumors derived from them.
As a result, a complex tamoxifen receptor transfer cofactor”, which, translocating to cell nucleus , prevents hypertrophy of estrogen-dependent cells.
The Sports Wiki states that the substance was first synthesized in 1971 and became the first antiestrogen among members of the class of selective estrogen receptor modulators (EMREs).
Renders antigonadotropic effect and suppress education prostaglandins in tumor tissue , slows down the development of the tumor process, which is stimulated.
After taking a single dose of the drug, the ability to block estrogens persists for several weeks.
Promotes release pituitary gonadotropic hormones , thereby causing ovulation women in her absence. At oligospermia increases serum concentration in men estrogen , luteotropin and follitropin .
Tamoxifen and some of its metabolites exhibit the properties of powerful inhibitors (oxidases) with mixed functions (monooxygenases) of the liver cytochrome P450 system. However, how clinically significant these effects are is not known exactly.
In some cases, Tamoxifen is effective in estrogen-independent tumors . The substance has a partial estrogen-like effect on the lipid spectrum, and bone tissue .
Absorption of Tamoxifen is high, TCmax is 4 to 7 hours after oral administration of the tablet. Steady-state plasma concentration is observed 4 weeks after the start of treatment with a dosage of 40 mg / day.
FROM blood plasma albumin the substance binds to 99%. Metabolization occurs in the liver by demethylation, hydroxylation and conjugation, and with the participation of the CYP2C9 isoenzyme.
Metabolites are excreted mainly with the contents intestines and partly kidneys (minor amount). The extraction is carried out in two stages. Initial period the half-life of the main metabolite circulating in the systemic circulation is from 7 to 14 hours, the final slow half-life is 7 days.
Indications for use
The use of Tamoxifen is advisable for:
- estrogen sensitive tumors ;
- malignant damage to breast tissue (especially during the period in women);
- breast cancer , including in men after surgical removal of the genitals;
- ductal breast cancer (ductal carcinoma in situ);
- endometrial cancer .
Fareston or Tamoxifen - which is more effective?
Fareston - this is anticancer antiestrogen non-steroidal agent , which is based on the substance . The main features of the drug:
- the presence of a chlorine atom in its chemical structure (which makes the drug more stable in comparison with Tamoxifen);
- absence oncogenic effect ;
- the ability to induce apoptosis;
- effectiveness at RE-negative tumors .
According to clinical observations conducted within six months, it was found that when taking Fareston:
- changes in hormonal homeostasis are much more favorable than when taking Tamoxifen;
- changes that are less dangerous for the patient in terms of oncorisk develop;
- an order of magnitude less often there are undesirable side effects.
The studies also led to the conclusion that, as part of complex treatment, the influence of Fareston on the tumor process with progressive breast cancer more effective than the influence of its analogue: when it was used, patients had a complete remission much more often, and the progression of the disease began 1.2 months later.
Besides, antitumor effect during treatment Fareston noted at more female patients.
Some facts about the product:
Instructions for use
Price in the online pharmacy site: from 53
Pharmacological properties
Composition and form of release
In the formula of the drug, the main active element is tamoxifen citrate. The product is made in tablet form.
Indications for use
The chemical product is prescribed in case of:
With established breast oncology, the chemical product is prescribed as an additional remedy for the main types of therapy: drug, surgical or radiological. For the male sex, a pharmacological drug is indicated for benign growth of the mammary glands, if this is associated with the use of anabolic steroids. For elderly people, the chemical product is prescribed exclusively by a doctor.
International Classification of Diseases (ICD-10)
C50 Breast cancer; C54.1 Endometrial cancer.
Side effects
The list of possible collateral complications associated with the administration of a pharmaceutical preparation is very extensive and includes the following phenomena:
Contraindications
Medication Tamoxifen is prohibited for appointment with:
Application during pregnancy
The drug during the period of gestation and lactation is prohibited for use.
Method and features of application
The Tamoxifen treatment regimen is set for each patient individually, taking into account the test data. For breast tissue cancer, the daily norm is 20-40 mg. The medication is taken immediately, or divided into two doses in the morning or evening time. The dosage of pharmaceuticals for endometrial tumors should not exceed 30 mg with a single or double dose during the day. Treatment with the use of a chemical preparation is quite long and is carried out until the symptoms of the disease disappear. The goal of therapy is to maintain a positive effect under the condition of constant administration of the drug. If necessary, the chemical product is prescribed as an additional agent during irradiation or in combination with cytostatics. The daily dose of the material taken should not exceed 40 mg. Tablets are swallowed whole, not chewed. You can drink a small amount of water. With a single dose, it is advisable to use the medicine in the morning. In the case of the introduction of anabolic-androgenic steroids, Tamoxifen is used starting from the second week of the steroid series. This is due to an increase in estrogen levels at the end of the first seven days of using anabolic agents. Sometimes it is advised to administer the drug until the onset of the next cycle.
Interaction with other drugs
As a result of the combination of the drug with indirect anticoagulants, the action of the latter is enhanced. This requires constant monitoring of the patient's health in order to timely adjust the dosage of anticoagulants. In the case of taking Tamoxifen tablets in combination with letrozole, its density in the plasma of the blood medium decreases. Cytostatic pharmaceuticals used in conjunction with the drug in question increase the likelihood of developing blockage of blood vessels by blood clots. In combination with tegafur, the formation of cirrhosis of the liver tissue is possible, followed by the formation of signs of hepatitis. When co-administered with chemicals containing female hormones - estrogens, for example, contraceptive drugs, there is a weakening of the effectiveness of both drugs. Pharmaceutical products that reduce the amount of excreted calcium cations, such as thiazide diuretics, increase the risk of developing elevated levels of calcium in the blood substance. The complex administration of Bromocriptine and Tamoxifen leads to an increase in the density of the latter in the blood serum. Means used to reduce the acidity of gastric secretions, which include antacids and antihistamines, provoke an early onset of dissolution of the protective surface of the capsules. The shell must retain its protective functions until the drug enters the intestinal section. For this reason, the time of taking antiestrogen tablets and antacids should not coincide by at least one hour.
Overdose
As a result of the introduction of overdoses, significantly exceeding the prescribed amount of the drug, segmental reflexes increase due to the weakening of the processes of inhibition of the cerebral cortex. Also, against the background of an overdose, the following symptoms are noted: dizziness, trembling of the limbs, gait disturbance. In this case, the use of the drug is canceled and symptomatic treatment is carried out.
Analogues
Tamoxifen has two types of alternative means: according to the structural composition and the principle of action. Structural analogues include: Vero-Tamoxifen, Tamoxifen-Ebewe, Tamoxifen-Feren and others. Fareston and Faslodex have a similar effect.
Terms of sale
The drug is sold in the pharmacy network without a prescription.
Storage conditions
In accordance with the instructions for use, the medication must be kept in a protected from sunlight place. The shelf life of the chemical preparation is no more than 2 years.
Men take tamoxifen to save muscle mass and preventing the development of gynecomastia (breast growth).
What is tamoxifen?
Tamoxifen citrate, best known under the trade name Nolvadex, or Nolvadex (Nolvadex), refers to specific estrogen receptor modulators (SERMs). The powerful and effective Nolvadex was developed to combat estrogen in breast cancer patients. Estrogens (female hormones) bind to receptors in the chest area and promote the development of tumors. Tamoxifen prevents this binding. The effect on the brain is that tamoxifen prevents the conversion of testosterone to estrogen, so the level of the female hormone remains low.
Tamoxifen in men is also used after a course of anabolic steroids to stimulate the natural production and increase of testosterone, which was suppressed due to the use of steroids.
In this case, tamoxifen stimulates the production of luteinizing () and follicle-stimulating hormones () by the pituitary gland, which, in turn, affect the production of testosterone in men. Without LH and FSH, there is no natural testosterone production; LH plays a major role in this process. Because of this effect, tamoxifen is sometimes prescribed for men to treat infertility.
TAMOXIFEN FOR GYNECOMASTIA IN MEN
Initially, tamoxifen preparations were used to fight breast cancer, but now they are increasingly used by men taking anabolic steroids.
Tamoxifen in this case helps to avoid aromatization and prevent the development of gynecomastia (growth of the mammary glands in men). Aromatization converts testosterone (male hormone) into estrogen (female hormone), as estradiol levels increase and receptor action increases, gynecomastia develops. Tamoxifen binds to receptors, thereby preventing estrogen binding and the development of this condition.
Another use of tamoxifen in men is antiandrogen therapy.
This type of hormonal treatment is often used in the treatment of prostate cancer. It slows down the growth of cancer cells and relieves symptoms in many men by lowering testosterone levels, but can cause a number of side effects due to. For example, they can increase the level of estrogens, which stimulate the growth of breast tissue, which leads to gynecomastia and pain in the mammary glands.
Recent studies have shown that tamoxifen can be used as an alternative to surgical treatment of gynecomastia in men. Tamoxifen is effective in treating breast problems caused by antiandrogen therapy in men (eg, in the treatment of prostate cancer) compared to radiation therapy or anastrozole (Arimidex is an antineoplastic drug, an aromatase inhibitor).
TAMOXIFEN: SIDE EFFECTS IN MEN
Although tamoxifen does effective drug for men, he can call side effects. The most common problems are associated with extremely long-term use, for example in patients with breast cancer.
With long-term use, tamoxifen citrate may suppress the production of insulin-like growth factor-1 (IGF-1) to some extent.
The peptide hormone IGF-1 is considered more powerful than growth hormone itself for building muscle tissue. However, when taking most anabolic steroids, IGF-1 increases dramatically, and tamoxifen will not be able to strongly suppress it.
Although tamoxifen is classified as an estrogen antagonist (adversary), tamoxifen actually works as an estrogen agonist in some parts of the body. This means that it works like estrogen.
For example, by acting in this way in the liver, tamoxifen can increase levels of sex hormone-binding globulin (SHGB) in men, which deactivates testosterone, thereby decreasing it in the body. Free testosterone is the unbound testosterone in the body, and it is this level that is highly correlated with the positive effects of high testosterone, such as increased muscle mass, strength, and libido. By lowering free testron, tamoxifen can impair muscle building, so it should not be taken in isolation from other muscle building drugs. Despite a significant increase in testosterone due to tamoxifen, the effect of the main male hormone is leveled due to an increase in SHBG.
Other side effects of tamoxifen in men include:
- Decrease in cognitive abilities (thinking, memory, etc.) (9% of men).
- Weight gain (22% of men).
- Sexual disorders (22%).
- Hot flashes (13%).
- Blood clotting, risk of thrombosis (9%).
- Vision problems (3% of men).
For example, in one study of 64 men who received tamoxifen, 13 (20%) stopped taking it, either on their own or at the direction of their doctors, due to unacceptable side effects of the treatment.
One of the drugs that are widely used to treat oncological processes is Tamoxifen. Instructions for use informs that this is not its only therapeutic effect.
What is this drug
Tamoxifen is medicine from the group of selective estrogen receptor inhibitors. Its active principle is tamoxifen citrate, which has a fairly powerful antitumor activity. For the first time, such a drug was obtained in the laboratory in 1971.
How does the drug work
This drug has various effects. After absorption, it spreads throughout the body and, acting on estrogen receptors, has a rather weak estrogen effect. In this case, there is a “closing” of targets for interaction with natural estrogen, which is produced in the ovaries. This leads to the fact that the active effect of the hormone on the tumor does not occur, and the growth of cancer stops. In clinical studies, it was noted that "Tamoxifen" has bipolar properties: estrogenic and anti-estrogenic effects. It also helps to reduce the level of prolactin in the blood. But in any case, the antitumor effect of the drug "Tamoxifen" is noted. Instructions for use informs that this is its main action in hormone-dependent tumors. At the same time, a pronounced clinical remission is observed when using the drug for 3-5 years. This suggests that the drug "Tamoxifen" contributes to the establishment of hormonal balance and homeostatic balance. In addition, there is no evidence that the drug has a cytostatic effect, that is, it directly stops tumor growth by direct action on cells.
In addition, tamoxifen citrate inhibits the formation of prostaglandins by tumor cells, which also stops the further progression of the tumor process. Another important indirect positive effect of the drug: acting on the pituitary gland, it enhances the production of gonadotropic hormones, which leads to a decrease in the production of its own estrogen and the resumption of ovulation in its absence.
Treatment of oncological processes
Breast cancer is the main use of Tamoxifen. Instructions for use advises using it as an independent method of treatment, as well as one of the components of complex therapy after mastectomy in conjunction with chemotherapy. This drug is also shown for the prevention of carcinoma, if there is a hereditary predisposition, since the drug blocks estrogen receptors and healthy cells. In some cases, a medication is also used to treat hormone-independent ovarian and endometrial cancer. In men, the drug is used to treat breast, kidney, and prostate cancer. Melanoma or soft tissue sarcoma are tumors that are hormone-dependent, and the action of this antiestrogen on them stops the further spread of the pathological process. In some cases, without this drug, it is impossible to achieve stabilization or stop the growth of the tumor.
Another useful feature
Another property is informed by the instructions for use attached to the Tamoxifen preparation. For men who are engaged in bodybuilding and weightlifting, the drug can be very useful. The drug is classified as a sex hormone, and not anabolic or androgen, which bodybuilders and powerlifters like to take. But the intake of anabolic substances is impossible without Tamoxifen, since anabolics, namely their flavoring components, provoke the accumulation of a large amount of estrogens in the blood, which leads to an increase in fat cells in the subcutaneous fat, growth of the mammary glands and swelling of all organs and tissues. "Tamoxifen" does not kill estrogens, does not reduce their amount in the blood, but it blocks estrogen receptors, which leads to positive effects:
- fat burning;
- removal of excess fluid from the body;
- increase in muscle density.
Men with oligospermia are also prescribed this drug, as it increases the amount of estrogens, testosterone and pituitary hormones in the blood, which leads to an increase in sperm quality, an increase in the percentage of live spermatozoa.
Contraindications for use
Patients who have individual intolerance should not be used for the treatment of Tamoxifen. Instructions for use also advises not to use the drug during pregnancy and lactation. But most often the medicine is prescribed in menopause, when the probability of pregnancy is zero. The drug is contraindicated in patients with thrombocytopenia, hyperlipidemia, leukopenia. Without prior blood donation for a biochemical and clinical study, the drug is not prescribed. With caution, under the control of the results of blood tests, "Tamoxifen" is prescribed if there are concomitant diseases: thrombophlebitis, thromboembolic disease, various eye diseases, especially cataracts, severe liver diseases.
Side effect
Good tolerability of the drug "Tamoxifen" was noted. Instructions for use inform that there are many side effects: nausea, vomiting, dizziness, loss of appetite, soreness in the mammary glands, skin rashes, bleeding from the vagina, hot flashes, thinning and hair loss, a slight increase in body weight and symptoms of hypercalcemia:
- drowsiness;
- depression;
- psychosis;
- hypertension;
- bradycardia;
- urolithiasis disease;
- nephrocalcinosis;
- polyuria;
- metastatic calcification.
But these symptoms appear only in case of an overdose of the drug or with prolonged use. Treatment with the drug "Tamoxifen" is canceled in the case when all these symptoms are not eliminated by reducing the dose or increasing the intervals between doses.
Forms of release and methods of application
The drug is available in tablet form. They contain 10, 20, 30, 40 mg of the active substance of the Tamoxifen tablet. Instructions for use, reviews suggest that the most appropriate application regimen is a gradual increase in the number of tablets taken. The increase should occur every week under the control of general well-being and the results of blood tests. The first week - 1 tablet 10 mg 2 times a day, the second week - 1.5 tablets, the third week - 2 tablets 2 times a day, and so on. Gradually, the dose can be increased to 60 mg per day in 3 divided doses. You should never do it yourself, only your doctor can prescribe a dosage for you and control the therapeutic effect and side effects.
When studying the description of the drug, many people have a question about how to take Tamoxifen. Does the instructions for use before meals or after recommend drinking it? Tablets are drunk 15 minutes after a meal. You need to drink at least 100 grams of water. The course of treatment is 3-4 months, then a break, after which it is continued according to this scheme up to 2-3 years, and in some cases up to 5 years.
Preparations-analogues. Their price
The drug is manufactured by pharmacological companies in Russia, Ukraine, India, Finland, as well as Hungary, the Czech Republic, Germany, England and others. In Russia, Tamoxifen Geksal and Vero Tamoxifen are most often prescribed. Instructions for use informs that these are absolutely identical tablets in composition, even excipients are the same. Therefore, the effectiveness of the antitumor effect does not differ from the effects of conventional Tamoxifen.
And if the cost of "Tamoxifen" produced in Finland is 80-90 rubles of the Russian Federation, then "Vero Tamoxifen", which is produced by the Russian company "Veropharm", has a lower price: 30 tablets of 10 mg can be bought for 60 rubles of the Russian Federation.
The German company Salutas produces Tamoxifen Geksal. Instructions for use informs that the medicine is taken in the same mode as Tamoxifen. The cost of the drug is 80-90 rubles of the Russian Federation.
Analogues of "Tamoxifen" - "Bilem", "Cemide", "Nolvadex", "Oncotam", "Cytosonium", "Moxifen", etc. All these drugs have the same active ingredient as "Tamoxifen". Instructions for use (analogs of the drug have the same) informs that the quality does not depend on the name, and the use of drugs is the same. Accordingly, both the dosage and the duration of administration do not change.
Compatibility with other drugs
If contraceptives are used together with Tamoxifen, then their effectiveness is reduced, so it is necessary to protect yourself by other methods.
When used together with cytostatics, the risk of thrombosis increases.
The antimetabolite "Tegafur", which is used to treat stomach cancer, together with "Tamoxifen" can provoke cirrhosis of the liver or hepatitis. "Bromocriptine" increases the concentration of tamoxifen in the blood.
Thiazide diuretics, which reduce calcium excretion, together with tamoxifen, can cause hypercalcemia.