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Progestediol Actions |
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Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, Estradiol (Progestediol) is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level.
The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of Estradiol (Progestediol) daily, depending on the phase of the menstrual cycle. After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone in the peripheral tissues. Thus, estrone and the sulfate conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women.
Estrogens act through binding to nuclear receptors in estrogen-responsive tissues. To date, two estrogen receptors have been identified. These vary in proportion from tissue to tissue.
Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH), and FSH, through a negative feedback mechanism. Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.
Endogenous Progesterone (Progestediol) is secreted by the ovary, placenta, and adrenal gland. In the presence of adequate estrogen, Progesterone (Progestediol) transforms a proliferative endometrium into a secretory endometrium.
Progesterone (Progestediol) enhances cellular differentiation and generally opposes the actions of estrogens by decreasing estrogen receptor levels, increasing local metabolism of estrogens to less active metabolites, or inducing gene products that blunt cellular responses to estrogen. Progesterone (Progestediol) exerts its effects in target cells by binding to specific Progesterone (Progestediol) receptors that interact with Progesterone (Progestediol) response elements in target genes. Progesterone (Progestediol) receptors have been identified in the female reproductive tract, breast, pituitary, hypothalamus, and central nervous system.
Take Progestediol only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.
Progestediol should come with a patient information leaflet. Read and follow these instructions carefully. Ask your doctor if you have any questions.
Take Progestediol with food.
Do not eat grapefruit or drink grapefruit juice while you are using Progestediol. Grapefruit and grapefruit juice may change the amount of Progestediol that is absorbed in the body.
The dose of Progestediol will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of Progestediol. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
If you miss a dose of Progestediol, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
If you miss a dose and it is more than 2 hours until your next dose, take the missed dose as soon as possible with food, then go back to your regular time.
If you miss a dose and it is within 2 hours of your next evening dose, skip the missed dose and go back to your regular dosing schedule.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Oral: Administer in the evening with food. In case of missed dose, administer with food as soon as possible, unless it is ≤2 hours until the next dose.
Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, Estradiol (Progestediol) is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level.
The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of Estradiol (Progestediol) daily, depending on the phase of the menstrual cycle. After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone in the peripheral tissues. Thus, estrone and the sulfate conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women.
Estrogens act through binding to nuclear receptors in estrogen-responsive tissues. To date, two estrogen receptors have been identified. These vary in proportion from tissue to tissue.
Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH), and FSH, through a negative feedback mechanism. Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.
Endogenous Progesterone (Progestediol) is secreted by the ovary, placenta, and adrenal gland. In the presence of adequate estrogen, Progesterone (Progestediol) transforms a proliferative endometrium into a secretory endometrium.
Progesterone (Progestediol) enhances cellular differentiation and generally opposes the actions of estrogens by decreasing estrogen receptor levels, increasing local metabolism of estrogens to less active metabolites, or inducing gene products that blunt cellular responses to estrogen. Progesterone (Progestediol) exerts its effects in target cells by binding to specific Progesterone (Progestediol) receptors that interact with Progesterone (Progestediol) response elements in target genes. Progesterone (Progestediol) receptors have been identified in the female reproductive tract, breast, pituitary, hypothalamus, and central nervous system.
No specific pharmacodynamic studies were conducted with Progestediol (Progestediol) capsules, 1 mg/100 mg.
Absorption
The oral absorption of both Progestediol is subject to first pass metabolism. After multiple doses of Progestediol (Progestediol) capsules, 1 mg/100 mg, the tmax (the time at which the maximum concentration is attained) for Estradiol (Progestediol) is approximately 5 hours and approximately 3 hours for Progesterone (Progestediol) (Figure 1, Figure 2, and Table 2, below). Steady state for both Progestediol components of Progestediol, as well as Estradiol (Progestediol)'s main metabolite, estrone, is achieved within seven days.
Figure 1: Mean Steady-State Serum Estradiol (Progestediol) Concentrations Following Daily
Oral Administration of 1 mg Estradiol (Progestediol)/100 mg Progesterone (Progestediol) (Baseline Unadjusted, at Day 7)
Figure 2: Mean Steady-State Serum Progesterone (Progestediol) Concentrations Following Daily
Oral Administration of 1 mg Estradiol (Progestediol)/100 mg Progesterone (Progestediol) (Baseline Unadjusted, at Day 7)
Dosage Strength (Progestediol) | Progestediol 1 mg/100 mg Mean (SD) | |
---|---|---|
*Effective t½. Calculated as 24•ln(2)/ ln(accumulation ratio/(accumulation ratio-1)) for subjects with accumulation ratio >1. | ||
Abbreviations: AUC0-τ = area under the concentration vs time curve within the dosing interval at steady-state, Cavg = average concentration at steady-state, Cmax = maximum concentration, SD = standard deviation, tmax = time to maximum concentration, t½ = half-life | ||
Estradiol (Progestediol) | N | |
AUC0-τ (pg·h/mL) | 20 | 772.4 (384.1) |
Cmax (pg/mL) | 20 | 42.27 (18.60) |
Cavg (pg/mL) | 19 | 33.99 (14.53) |
tmax (h) | 19 | 4.93(4.97) |
t½ (h)* | 19 | 26.47 (14.61) |
Estrone | ||
AUC0-τ (pg·h/mL) | 20 | 4594 (2138) |
Cmax (pg/mL) | 20 | 238.5 (100.4) |
Cavg (pg/mL) | 20 | 192.1 (89.43) |
tmax (h) | 20 | 5.45 (3.47) |
t½ (h)* | 19 | 22.37 (7.64) |
Progesterone (Progestediol) | ||
AUC0-τ (ng·h/mL) | 20 | 18.05 (15.58) |
Cmax (ng/mL) | 20 | 11.31 (23.10) |
Cavg (ng/mL) | 20 | 0.76 (0.65) |
tmax (h) | 20 | 2.64 (1.51) |
t½ (h) | 18 | 9.98 (2.57) |
Food Effect
Concomitant food ingestion increased the AUC and Cmax of the Progesterone (Progestediol) component of Progestediol relative to a fasting state when administered at a dose of 100 mg. In a study where Progestediol was administered to postmenopausal women at a dose of 1 mg Estradiol (Progestediol)/100 mg Progesterone (Progestediol) within 30 minutes of starting a high-fat meal, the Cmax and AUC of Progesterone (Progestediol) were 162% and 79% higher, respectively, relative to the fasting state. Concomitant food ingestion had no effect on the AUC of the Estradiol (Progestediol) component of Progestediol but decreased Cmax by approximately 54% and delayed Tmax to 12 hours.
Distribution
Estradiol (Progestediol)
The distribution of exogenous estrogens is similar to that of endogenous estrogens. Estrogens are widely distributed in the body and are generally found in higher concentrations in the sex hormone target organs. Estrogens circulating in the blood largely are bound to SHBG and albumin.
Progesterone (Progestediol)
Progesterone (Progestediol) is approximately 96% to 99% bound to serum proteins, primarily to serum albumin (50% to 54%) and transcortin (43% to 48%).
Elimination
Following repeat dosing with Progestediol (Progestediol) capsules, 1 mg/100 mg, the half-life of Estradiol (Progestediol) was approximately 26 hours. The half-life of Progesterone (Progestediol), following repeat dosing was approximately 10 hours.
Metabolism
Estradiol (Progestediol)
Exogenous estrogens are metabolized in the same manner as endogenous estrogens. Circulating estrogens exist in a dynamic equilibrium of metabolic interconversions. These transformations take place mainly in the liver. Estradiol (Progestediol) is converted reversibly to estrone, and both can be converted to estriol, the major urinary metabolite. Estrogens also undergo enterohepatic recirculation via sulfate and glucuronide conjugation in the liver, biliary secretion of conjugates into the intestine, and hydrolysis in the gut followed by reabsorption. In postmenopausal women, a significant portion of the circulating estrogens exist as sulfate conjugates, especially estrone sulfate, which serves as a circulating reservoir for the formation of more active estrogens.
Progesterone (Progestediol)
Progesterone (Progestediol) is metabolized primarily by the liver largely to pregnanediols and pregnanolones. Pregnanediols and pregnanolones are conjugated in the liver to glucuronide and sulfate metabolites. Progesterone (Progestediol) metabolites, which are excreted in the bile, may be deconjugated and may be further metabolized in the intestine via reduction, dehydroxylation, and epimerization.
Excretion
Estradiol (Progestediol)
Estradiol (Progestediol), estrone, and estriol are excreted in the urine along with glucuronide and sulfate conjugates.
Progesterone (Progestediol)
The glucuronide and sulfate conjugates of pregnanediol and pregnanolone are excreted in the bile and urine. Progesterone (Progestediol) metabolites are eliminated mainly by the kidneys. Progesterone (Progestediol) metabolites which are excreted in the bile may undergo enterohepatic recycling or may be excreted in the feces.
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Information checked by Dr. Sachin Kumar, MD Pharmacology
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