Ovestin, vaginal cream 1 mg/g 15 g

Pharmacotherapeutic group: Natural and synthetic estrogens
ATX code: G03CA04

Pharmacological properties

Pharmacodynamics
.
The active ingredient of the drug is estriol – an analogue of the natural female hormone estriol. It replenishes estrogen deficiency in postmenopausal women and relieves postmenopausal symptoms. Estriol is most effective in the treatment of urinary and reproductive tract disorders (e.g. atrophic vaginitis). In atrophy of lower urinary and genital tract mucosa, estriol induces normalization of vaginal, cervical and urethral epithelium, thus contributing to restoration of normal vaginal microflora and pH. As a result the resistance of urinary and genital tract epithelium to infection and inflammation increases; dry mucous membranes and vaginal itching, pain during intercourse and probability of vaginal and urinary tract infections decrease; therapy with estriol promotes normalization of urination and prevents urinary incontinence.
Unlike other estrogens, estriol has a short period of action (it is retained in the nuclei of endometrial cells for a short period of time). It is assumed that a single daily dose does not cause endometrial proliferation. Therefore, no cyclic progestagen administration is required and no “withdrawal” bleeding occurs.

Pharmacokinetics

Absorption
Intravaginal administration of estriol provides optimal bioavailability at the site of action. Estriol is also absorbed and enters the general circulation, which is manifested by a rapid increase in plasma concentrations of unbound estriol.

Distribution
In plasma almost all (90%) estriol is bound to albumin and, unlike other estrogens, is virtually unbound to sex hormone binding globulin (HSPG).
Maximum concentration in plasma is observed 1-2 hours after administration. After intravaginal administration of 0.5 mg of estriol, Cmax is approximately 100 pg/mL, Cmin is approximately 25 pg/mL, and the mean is approximately 70 pg/mL. After daily intravaginal administration of 0.5 mg of estriol for three weeks, the Cmax decreased to 40 pg/mL.
After using the drug for 21 months (median, ICR, 9.2-38.4) on a 3 times-weekly regimen, the median serum estriol concentration in the long-term use group was 5.5 pg/mL (ICR, 1.9-10.2).

Metabolism
The metabolism of estriol consists mainly of conversion to conjugated and unconjugated states during enterohepatic circulation.

Elimation
Estriol, being the end product of metabolism, is mainly excreted through the kidneys in bound form. And only a small portion (± 2%) is excreted with the bile through the intestine, mainly in the form of unbound estriol.
Estriol elimination half-life is 6-9 hours.

Indications

Active ingredient

Composition

How to take, the dosage

Interaction

Special Instructions

Synopsis

Contraindications

Side effects

Classes and organ systems

Unwanted reactions

Frequency

Metabolic and nutritional disorders

Fluid retention

Frequency unknown

Gastrointestinal disorders

Nausea

/p>

Frequency unknown

Genital and breast disorders

Mammary gland pain, pain in the breasts; uterine discharge in the postmenopause; discharge from the cervix

Frequency unknown

Irritation and itching at the application site; flu-like symptoms

Frequency unknown

Age range

(years)

Incidence per 1,000 women who took placebo for more than 5 years (placebo group)

Relative risk (95% CI)

Additional cases per 1,000 patients receiving ZGT for 5 years

Peroral estrogen monotherapy*

50-59

7

1.2 (0.6-2.4)

1 (- 3-10)

* Study in women who have had a hysterectomy

Age range

(years)

Incidence per 1,000 women taking placebo for 5 years (placebo group)

/p>

Relative risk (95% CI)

/td>

Additional cases per 1,000 patients receiving ZGT for 5 years

/p>

50-59

8

1.3 (1.1-1.6)

3 (1-5)

*Ischemic and hemorrhagic strokes were not distinguished.

Overdose

Pregnancy use

Similarities