Description
Buserelin Pharmacodynamics
A synthetic analogue of natural gonadotropin-releasing hormone (GnRH). Buserelin competitively binds to the receptors of the cells of the anterior pituitary lobe, causing a short-term increase in the level of sex hormones in the blood plasma. Further use of the therapeutic doses of the drug leads (on average, after 12-14 days) to a complete blockade of the gonadotropic function of the pituitary gland, thus inhibiting the release of luteinizing (LH) and follicle stimulating hormone (FSH). As a result, there is a suppression of sex hormone synthesis in the gonads, which is manifested by a decrease in plasma estradiol concentration to postmenopausal values in women and a decrease in testosterone to post-castration levels in men.
Testosterone concentration with continuous treatment for 2-3 weeks decreases to the content characteristic of the orchiectomy state, i.e. pharmacological castration is induced.
Indications
Hormone-dependent prostate cancer;
Breast cancer;
Endometriosis (pre- and postoperative periods);
Uterine myoma;
Hyperplastic processes of the endometrium;
Treatment of infertility (during the program of in vitro fertilization (IVF).
Contraindications
Pregnancy;
Breast-feeding period;
Hypersensitivity to the components of the drug.
Pregnancy and lactation:
The drug is contraindicated in pregnant and lactating women.
Dosage and administration
- In cases of hormone-dependent prostate cancer – 3.75 mg intramuscularly (v/m) every four weeks;
- In treatment of endometriosis, hyperplastic processes of endometrium – 3.75 mg intramuscularly once every 4 weeks. Treatment should be started in the first five days of the menstrual cycle. The duration of treatment is 4 to 6 months;
- In the treatment of uterine myoma – 3.75 mg v/m once every 4 weeks.
- Treatment should be started in the first five days of the menstrual cycle. Duration of treatment – before surgery – 3 months, in other cases – 6 months;
- Infertility treatment by in vitro fertilization (IVF) – 3.75 mg/m once at the beginning of the folliculin phase (on the 2nd day of the menstrual cycle) or in the middle of the luteal phase (21 – 24 days) of the menstrual cycle preceding the stimulation. After a blockade of pituitary function confirmed by a decrease in the concentration of oestrogens in the blood serum by at least 50% of the initial level (usually determined 12-15 days after Buserelin-depo injection), in the absence of ovarian cysts (according to ultrasound) and endometrial thickness of no more than 5 mm, the stimulation of superovulation with gonadotropic hormones under ultrasound monitoring and control of serum oestradiol levels starts.
- Rules of suspension preparation and drug administration
-The drug is administered only intramuscularly.
-The suspension for intramuscular injection is prepared using the included solvent, immediately before administration.
-The drug should be prepared and administered only by specially trained medical personnel.
-Hold the vial of Buserelin-depo strictly vertically. Gently tap the vial so that all of the lyophilizate is at the bottom of the vial.
-Open the syringe, attach the needle with the pink pavilion (1.2 x 50 mm) to draw out the solvent.
-Open the ampoule and draw the entire contents of the solvent ampoule into the syringe, set the syringe. to a 2 ml dose.
-Remove the plastic cap from the vial containing the lyophilizate. Disinfect the rubber stopper of the vial with an alcohol swab. Insert the needle into the vial with the lyophilizate, through the center of the rubber stopper and carefully inject the solvent along the inner wall of the vial, without touching the contents of the vial with the needle. Remove the syringe from the vial.
-The vial must remain stationary until the lyophilizate is completely saturated with the solvent and a suspension is formed (about 3 – 5 minutes). After that, without turning the vial, one should check the presence of dry lyophilizate at the walls and bottom of the vial. If dry lyophilizate residue is found, leave the vial until it is completely saturated.
-After verifying that there is no residual dry lyophilizate, the contents of the vial should be stirred gently in a circular motion for 30-60 seconds until a homogeneous suspension is formed. Do not invert or shake the vial, this may cause flakes to fall out and the suspension to become unusable.
-Fast insert the needle through the rubber stopper into the vial. Then slice, needle down and, tilting the vial at a 45 degree angle, slowly draw the entire suspension into the syringe. Do not invert the vial as you draw. A small amount of the drug may remain on the walls and the bottom of the vial. The flow rate for the residue on the walls and the bottom of the vial is counted.
-Immediately replace the pink pavilion needle with a green pavilion needle (0.8 x 40 mm), carefully invert the syringe and remove the air from the syringe.
-The Buserelin-depo suspension should be administered immediately – after preparation.
-Use an alcohol swab to disinfect the injection site. Insert the needle deep into the gluteal muscle, then pull the syringe piston back slightly to make sure there is no damage to the vessel. Inject the suspension intramuscularly slowly with constant pressure on the syringe plunger. If the needle becomes blocked, replace it with another needle of the same diameter. - Precautions for use.
- In women.
- Patients with any form of depression during Buserelin-depo treatment should be under close medical supervision.
- Ovulation induction should be performed under close medical supervision.
- At the initial stage of treatment with the drug, ovarian cysts may develop.
- It is recommended to avoid pregnancy and stop taking hormonal contraceptives before starting treatment with the drug, but other (non-hormonal) contraceptive methods must be used during the first two months of using the drug.
- In men
- For effective prevention of possible side effects during the first phase of the drug it is necessary to use antiandrogens two weeks before the first injection of Buserelin – depot and during two weeks after the first injection.
