BIJUVA

Indications

• Menopausal symptoms
• Osteoporosis prophylaxis
• Irregular menstruation
• Vulvovaginal atrophy
• Postmenopausal urogenital conditions

Dosage

Adults: The typical adult dosage of estradiol is 2 mg daily, initiated on day 1-5 of the menstrual cycle or at any time if cycles have ceased or are infrequent, taken with

Mechanism of action

Estradiol exerts its effects by binding to estrogen receptors, specifically estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ), as well as the G protein-coupled estrogen receptor (GPER). This binding triggers the receptor-ligand complex to translocate to the nucleus, where it regulates gene transcription and the synthesis of specific proteins that mediate estradiol's physiological effects.

Pharmacodynamics

Estradiol acts on estrogen receptors to alleviate vasomotor symptoms such as hot flashes and urogenital symptoms including vaginal dryness. It has beneficial effects on bone density by inhibiting bone resorption and improving plasma lipid profiles. Additionally, estradiol decreases follicle-stimulating hormone (FSH) levels by suppressing its formation in the anterior pituitary gland. Notably, it may increase the risk of cardiovascular events, venous thromboembolism, and stroke, necessitating caution in high-risk populations.

Pharmacokinetics

Estradiol is rapidly absorbed when administered orally, with a bioavailability affected by first-pass metabolism in the liver. It is extensively metabolized in the liver, conjugated to form estrone and estrone sulfate, and eliminated through urine. The half-life of estradiol varies depending on the route of administration, with peak plasma concentrations occurring within 1-3 hours post-administration. Continuous use can lead to accumulation and requires careful monitoring of therapy duration and dosage adjustments.

Contra-indications

• History of thromboembolic disorders
• Known or suspected estrogen-dependent tumors
• Undiagnosed abnormal genital bleeding
• Severe liver dysfunction
• Pregnancy

Adverse effects

• Nausea
• Headaches
• Weight changes
• Breast tenderness
• Mood alterations
• Vaginal discharge
• Oedema
• Skin reactions
• Thromboembolic events
• Cerebrovascular accidents
• Endometrial hyperplasia
• Angioedema

Interactions

• Antiepileptics (carbamazepine, phenytoin, etc.) may decrease efficacy of estradiol
• Bosentan may decrease efficacy of estradiol
• Modafinil may decrease efficacy of estradiol
• Rifamycins may decrease efficacy of estradiol
• St. John's Wort may decrease efficacy of estradiol
• Ritonavir may decrease efficacy of estradiol

Precautions

• Monitor for signs of thromboembolic events
• Evaluate for endometrial hyperplasia in women with a uterus
• Consider cardiovascular risks before initiating therapy
• Assess liver function prior to use
• Use with caution in patients with a history of depression

Pregnancy

Estradiol is contraindicated in pregnancy due to potential harm to the fetus and increased risk of thromboembolic events.

Breast-feeding

Estradiol is excreted in breast milk; caution is advised when used by nursing mothers as it may affect milk production.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Tablets (1 mg, 2 mg)
• Vaginal ring (continuous use, replaced every 3 months)

Indications

• Hormonal contraception
• Menstrual irregularities
• Endometrial hyperplasia
• Hormone replacement therapy
• Support of early pregnancy

Dosage

Children: Refer to the BNF for Children for any paediatric dosing recommendations concerning the use of progesterone.

Adults: Refer to the BNF for specific adult dosage guidelines, particularly for hormonal contraception and other indications.

Mechanism of action

Progesterone binds and activates its nuclear receptor, PR, which is significant in maintaining the endometrium during preparation for pregnancy. The progesterone receptor modulates gene expression that regulates the development and differentiation of reproductive tissues. It alters the consistency of cervical mucus, making it less favorable for sperm penetration and inhibits follicle-stimulating hormone (FSH) to prevent ovulation.

Pharmacodynamics

Progesterone acts primarily on the uterus by converting the proliferative phase to the secretory phase of the endometrium, preparing it for implantation. It increases the vascularity of the endometrium and stimulates mucous secretion while providing negative feedback to the anterior pituitary to decrease levels of FSH and LH. Thus, it prevents ovulation and promotes conditions conducive to pregnancy.

Pharmacokinetics

Progesterone is absorbed after administration and is metabolized primarily in the liver. The half-life of progesterone varies, with an average of about 5 minutes in circulation, but it can exert effects for longer due to its action on target tissues. It is excreted mainly in urine as conjugated metabolites. The pharmacokinetics can be influenced by factors such as route of administration, with intramuscular and oral forms demonstrating different absorption and bioavailability profiles.

Contra-indications

• Undiagnosed vaginal bleeding
• Active or severe hepatic disease
• History of breast cancer or known or suspected sex hormone-dependent tumors

Adverse effects

• Menstrual cycle irregularities
• Breast tenderness
• Dizziness
• Headache
• Nausea
• Skin reactions
• Weight change
• Abdominal distension
• Depressed mood
• Appetite change
• Fatigue
• Hypertension
• Libido disorder
• Nervousness
• Rash

Interactions

• Norethisterone
• Other hormonal contraceptives
• Antibiotics (may reduce effectiveness of progestogen-only contraceptives)

Precautions

• Caution in hepatic impairment
• Monitor for signs of thromboembolism
• Consider potential delayed return to fertility after discontinuation

Pregnancy

Progesterone is essential for maintaining pregnancy. Its use in non-contraceptive doses may cause masculinisation of female fetuses.

Breast-feeding

Progestogen-only contraceptives do not affect lactation. Higher doses may alter milk composition. Withhold breastfeeding for neonates with severe jaundice requiring treatment.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Norethisterone 5 mg tablets
• Norethisterone enantate 200 mg/1 ml solution for injection
• Noriday 350 microgram tablets
• Primolut N 5 mg tablets
• Utovlan 5 mg tablets

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations.

Adults: Refer to the BNF for specific dosing recommendations.

Mechanism of action

The exact mechanism of action for Hemi is not explicitly detailed in the available resources, but compounds with similar structure may act by modulating neurotransmitter levels, inhibiting enzymes, or affecting cellular signaling pathways.

Pharmacodynamics

Hemi may exhibit pharmacodynamic properties that include modulation of neural activity or inhibition of specific biochemical pathways. Its effects could be dose-dependent and vary based on the therapeutic context.

Pharmacokinetics

The pharmacokinetic profile of Hemi, including absorption, distribution, metabolism, and excretion, is not well-documented in the provided resources. Generally, compounds in this class may undergo first-pass metabolism and have a variable half-life.

Dosage

Children: Refer to the specific formulation or active ingredient for dosing information.

Adults: Refer to the specific formulation or active ingredient for dosing information.

Mechanism of action

The mechanism of action of hemihydrate forms of drugs can vary widely depending on the specific compound. In many cases, the hemihydrate form enhances the solubility of the active ingredient, which facilitates its dissolution and absorption in the gastrointestinal tract.

Pharmacodynamics

Pharmacodynamics of hemihydrate compounds generally relates to the pharmacological effects that arise from the active drug once it is absorbed. The effects may vary based on the specific drug and its therapeutic target, but overall, the hemihydrate form aims to improve efficacy by ensuring adequate plasma concentrations are achieved more effectively than non-hydrated forms.

Pharmacokinetics

The pharmacokinetics of hemihydrate drugs typically demonstrate improved dissolution rates due to the presence of water, which can lead to increased absorption. This may result in quicker onset of action and modified half-lives. The specifics of absorption, distribution, metabolism, and excretion will depend on the active ingredient and its properties.

Pregnancy

Safety in pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

It is not known whether this drug is excreted in human milk. Caution should be exercised when administered to a nursing mother.

Storage

Store at room temperature, away from moisture and heat. Keep container tightly closed.

Mechanism of action

Estrogen is found in the the breast, uterine, ovarian, skin, prostate, bone, fat, and brain tissues. The main source of estrogen in adult women during the reproductive period of life is the ovarian follicle, which secretes 70 to 500 mcg of estradiol each day. After menopause, however, the majority of endogenous estrogen is produced by transformation of androstenedione (which is secreted by the adrenal cortex) to estrone in the peripheral tissues. Both estrone and its sulphate conjugated form, estrone sulphate, represent the most abundant estrogens found in postmenopausal women. Estradiol, however, is considerably more potent than estrone and estriol at the estrogen receptor (ER). As a result, the higher estrone concentration in postmenopausal population, can cause various undesirable effects. These effects may include hot flashes, chills, vaginal dryness, mood swings, irregular menstruation, and chills, in addition to sleep problems. Estradiol workings by binding to subtypes of the estrogen receptor: estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). It also exerts potent agonism of G Protein-coupled estrogen receptor (GPER), which is recognized an important regulator of this drug's rapid effects. Once the estrogen receptor has bound to its ligand, it enters the nucleus of the target cell, regulating gene transcription and formation of of messenger RNA. This mRNA makes contact with ribosomes producing specific proteins that express the effect of estradiol upon the target cell. Agonism of estrogen receptors increases pro-estrogenic effects, leading to the relief of vasomotor and urogenital symptoms of a postmenopausal or low estradiol state. 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 is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol at the receptor level. ... After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone by 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 follicle stimulating hormone (FSH), through a negative feedback mechanism. Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women. Estrogens have an important role in the reproductive, skeletal, cardiovascular, and central nervous systems in women, and act principally by regulating gene expression. Biologic response is initiated when estrogen binds to a ligand-binding domain of the estrogen receptor resulting in a conformational change that leads to gene transcription through specific estrogen response elements (ERE) of target gene promoters; subsequent activation or repression of the target gene is mediated through 2 distinct transactivation domains (ie, AF-1 and AF-2) of the receptor. The estrogen receptor also mediates gene transcription using different response elements (ie, AP-1) and other signal pathways. Recent advances in the molecular pharmacology of estrogen and estrogen receptors have resulted in the development of selective estrogen receptor modulators (eg, clomiphene, raloxifene, tamoxifen, toremifene), agents that bind and activate the estrogen receptor but that exhibit tissue-specific effects distinct from estrogen. Tissue-specific estrogen-agonist or -antagonist activity of these drugs appears to be related to structural differences in their estrogen receptor

Pharmacodynamics

Estradiol acts on the on the estrogen receptors to relieve vasomotor systems (such as hot flashes) and urogenital symptoms (such as vaginal dryness and dyspareunia). Estradiol has also been shown to exert favorable effects on bone density by inhibiting bone resorption. Estrogen appears to inhibit bone resorption and may have beneficial effects on the plasma lipid profile. Estrogens cause an increase in hepatic synthesis of various proteins, which include sex hormone binding globulin (SHBG), and thyroid-binding globulin (TBG). Estrogens are known to suppress the formation of follicle-stimulating hormone (FSH) in the anterior pituitary gland. **A note on hyper-coagulable state, cardiovascular health, and blood pressure** Estradiol may cause an increased risk of cardiovascular disease, DVT, and stroke, and its use should be avoided in patients at high risk of these conditions. Estrogen induces a hyper-coagulable state, which is also associated with both estrogen-containing oral contraceptive (OC) use and pregnancy. Although estrogen causes an increase in levels of plasma renin and angiotensin. Estrogen-induced increases in angiotensin, causing sodium retention, which is likely to be the mechanism causing hypertension after oral contraceptive treatment.

Mechanism of action

Progesterone binds and activates its nuclear receptor, _PR_, which plays an important part in the signaling of stimuli that maintain the endometrium during its preparation for pregnancy. Progesterone receptor (PR) is a member of the nuclear/steroid hormone receptor (SHR) family of ligand-dependent transcription factors that is expressed primarily in female reproductive tissue as well as the central nervous system. As a result of its binding its associated steroid hormone, progesterone, the progesterone receptor (PR) modulates the expression of genes that regulate the development, differentiation, and proliferation of target tissues. In humans, PR is found to be highly expressed in the stromal (connective tissue) cells during the secretory phase and during pregnancy. Progesterone may prevent pregnancy by changing the consistency of cervical mucus to be unfavorable for sperm penetration, and by inhibiting follicle-stimulating hormone (FSH), which normally causes ovulation. With perfect use, the first-year failure rate for progestin-only oral contraceptives is approximately 0.5%. The typical failure rate, however, is estimated to be approximately 5%, due to late or missed pills. Progesterone is a progestinic hormone secreted mainly from the corpus luteum of the ovary during the latter half of the menstrual cycle. Progesterone is formed from steroid precursors in the ovary, testis, adrenal cortex, and placenta. Luteinizing hormone (LH) stimulates the synthesis and secretion of progesterone from the corpus luteum. Progesterone is necessary for nidation (implantation) of the ovum and for maintenance of pregnancy. Although the hormone is secreted mainly during the luteal phase of the menstrual cycle, small amounts of progesterone are also secreted during the follicular phase. High concentrations of the hormone are secreted during the latter part of pregnancy. Amounts comparable to those secreted in women during the follicular phase have been shown to be secreted in males. Progesterone shares the pharmacologic actions of the progestins. In women with adequate endogenous estrogen, progesterone transforms a proliferative endometrium into a secretory one. The abrupt decline in the secretion of progesterone at the end of the menstrual cycle is principally responsible for the onset of menstruation. Progesterone also stimulates the growth of mammary alveolar tissue and relaxes uterine smooth muscle. Progesterone has minimal estrogenic and androgenic activity. Progesterone released during the luteal phase of the cycle decreases estrogen driven endometrial proliferation and leads to the development of a secretory endometrium ... . The abrupt decline in the release of progesterone from the corpus luteum at the end of the cycle is the main determinant of the onset of menstruation. If the duration of the luteal phase is artificially lengthened, either by sustaining luteal function or by treatment with progesterone, decidual changes in the endometrial stroma similar to those seen in early pregnancy can be induced. Under normal circumstances, estrogen antecedes and accompanies progesterone in its action upon the endometrium and is essential to the development of the normal menstrual pattern. Progesterone also increases the ventilatory response of the respiratory centers to carbon dioxide and leads to reduced arterial and alveolar PC02 in the luteal phase of the menstrual cycle and during pregnancy. Progesterone also may have depressant and hypnotic actions in the CNS, which may account for reports of drowsiness after hormone administration. For more Mechanism of Action (Complete) data for PROGESTERONE (12 total), please visit the HSDB record page.

Pharmacodynamics

Progesterone, depending on concentration and dosage form, and timing of exposure may have several pharmacodynamic effects. These actions, according, to various preparations, are listed below: General effects Progesterone is the main hormone of the corpus luteum and the placenta. It acts on the uterus by changing the proliferative phase to the secretory phase of the endometrium (inner mucous lining of the uterus). This hormone, stimulated by a hormone called _luteinizing hormone_ (LH) is the main hormone during the secretory phase to prepare the corpus luteum and the endometrium for implantation of a fertilized ovum. As the luteal phase concludes, the progesterone hormone sends negative feedback to the anterior pituitary gland in the brain to decrease FSH (follicle stimulating hormone) and LH (luteinizing hormone) levels. This prevents ovulation and maturation of oocytes (immature egg cells). The endometrium then prepares for pregnancy by increasing its vascularity (blood vessels) and stimulating mucous secretion. This process occurs by progesterone stimulating the endometrium to decrease endometrial proliferation, leading to a decreased uterine lining thickness, developing more complex uterine glands, collecting energy in the form of glycogen, and providing more uterine blood vessel surface area suitable for supporting a growing embryo. As opposed to cervical mucous changes observed during the proliferative phase and ovulation, progesterone decreases and thickens the cervical mucus, rendering it less elastic. This change occurs because the fertilization time period has passed, and a specific consistency of mucous amenable to sperm entry is no longer required. **Gelatinized capsules** Progesterone capsules are an oral dosage form of micronized progesterone which, chemically identical to progesterone of ovarian origin. Progesterone capsules have all the properties of endogenous progesterone with induction of a secretory phase endometrium with gestagenic, antiestrogenic, slightly antiandrogenic and anti-aldosterone effects. Progesterone opposes the effects of estrogen on the uterus, and is beneficial in women with unopposed estrogen exposure, which carries an increased risk of malignancy. **Vaginal gel and vaginal insert** The gel preparation mimics the effects of naturally occurring progesterone. In the presence of adequate levels of estrogen, progesterone converts a proliferative endometrium into secretory endometrium. This means that the endometrium changes from a growing and thickening stage into a subsequent preparation stage for pregnancy, which involves further preparatory changes. Progesterone is necessary for the development of decidual tissue (specialized tissue amenable to supporting a possible pregnancy). Progesterone is required to increase endometrial receptivity for the implantation of a fertilized embryo. Once an embryo is implanted, progesterone helps to maintain the pregnancy. **Injection (intramuscular)** Intramuscularly injected progesterone increases serum progesterone and aids in the prevention of endometrial tissue overgrowth due to unopposed estrogen (which leads to abnormal uterine bleeding and sometimes uterine cancer),. In the absence or deficiency of progesterone, the endometrium continually proliferates, eventually outgrowing its limited blood supply, shedding incompletely, and leading to abnormal and/or profuse bleeding as well as malignancy. **Tablets, contraceptive** Progesterone-only contraceptive tablets prevent conception by suppressing ovulation in about half of users, causing a thickening of cervical mucus to inhibit sperm movement, lowering the midcycle LH and FSH hormone peaks, slowing the movement of the ovum through the fallopian tubes, and causing secretory changes in the endometrium as described above.