Norethisterone acetate

The most commonly used oral progestogens are medroxyprogesterone acetate, micronized progesterone, and norethisterone acetate. 

Neven P, Lunde T, Benedetti-Panici P, Tiitinen A, Marinescu B, Villiers T, Hillard T, Cano A, Peer E, Quail D, Nickelsen T (2003) A multicentre randomised trial to compare uterine safety of raloxifene with a continuous combined hormone replacement therapy containing oestradiol and norethisterone acetate. Br J Obstet Gynaecol 110 157-167... 

Another approach to the study of the effects of hormone replacement therapy on the breast is to examine breast density, using mammography and the Wolfe classification. In a randomized study of 166 menopausal women, using this technique, there was increased breast density after 6 months of treatment eight times more commonly in those who took estradiol and norethisterone acetate than in those who took tibolone (186). The significance of this increased density is not clear, but it should for the present be regarded as undesirable,... 

The effect of continuously administered low-dose 17-beta-estradiol (E2) + norethisterone acetate (NETA) on coagulation and fibrinolytic factors has been studied in 120 menopausal women, using two dosage variations (1 mg of E2 with 0.25 mg or 0.5 mg of NETA) compared with placebo over a year (53). In either dose, the combination significantly lowered plasma concentrations of factor VII, fibrinogen, antithrombin, and plasminogen activator inhibitor-1 (PAI-1) compared with placebo. These changes appear favorable, since they may lead to increased fibrinolytic activity and could reduce the risk of coronary heart disease. However, antithrombin activity was also reduced, which may increase the risk of venous thromboembolism. 

Borgfeldt C, Li C, Samsioe G. Low-dose oral combination of 17beta-estradiol and norethisterone acetate in postmenopausal women decreases factor VII, fibrinogen, antithrombin and plasminogen activator inhibitor-1. Climacteric 2004 7 78-85. 

In 438 postmenopausal women, randomly assigned to either constant 17-beta-estradiol (1 mg/day) plus inter mittent norgestimate 90 micrograms (3 days off, 3 days on) or a fixed combination of 17-beta-estradiol (2 mg/ day) with norethisterone acetate (1 mg), the two regimens had similar bleeding profiles and provided comparable relief from vasomotor symptoms (1). However, breast discomfort and edema were experienced by twice as many subjects who used the fixed combination. The intermittent regimen was notably free of endometrial hyperplasia. 

The progestogens as a group have little effect on the liver. However, some progestogens can increase non-conju-gated bilirubin (29) norethisterone acetate has been implicated in this effect (30). 

In one of the largest international multicenter studies of raloxifene it was found that, compared with combined hormone replacement therapy (with 17-beta-oestradiol 2 mg + norethisterone acetate 1 mg) 12 months of raloxifene treatment at 60 mg/day was not associated with increased endometrial thickness or uterine volume (31). 

In a series of review papers Gergely et al. [21-23] reported the use of CD detection to solve various quantitative analytical problems. CD curves can, in some cases, be usefully applied to determine a, 0-unsaturated ketosteroid impurities in basic drug materials [21]. For instance ethynodiol is manufactured from norethisterone, so norethisterone acetate might always remain as an impurity in... 

From a quantitative study of model substances it was established that, for ethynodiol diacetate and norethynodrel contaminated with 0.05-5% norethisterone acetate and norethisterone respectively, the ellipticity varies linearly with the concentration and values that were found were in accordance with the results from the preceding difference spectrophotometric determination. 

Proprietary Names. Milligynon Norlutate Primolut Nor SH 420. Norethisterone acetate is an ingredient of many proprietary preparations—see Martindale, The Extra Pharmacopoeia, 28th Edn. 

Thin-layer Chromatography. Norethisterone system TP—Rf 71 system TQ—Rf 22 system TR—Rf 87 system TS—Rf 63, streaking may occur. Norethisterone acetate system TP—Rf 87 system TQ—Rf 39 system TR—Rf 98 system TS—Rf 90. 

Dose. 5 to 25 mg of norethisterone or 2.5 to 15 mg of norethisterone acetate daily doses of up to 60 mg daily have been given. 

Hydrocortisone Acetate Fluocortolone Pivalate Norethisterone Acetate... 

SYN S 17-P-ACETOXY-l 9-NOR-l 7-a-PREGN-4-EN-20-YN-3-ONE (17-a)-17-(ACETYLOXY)-19-NORPREGN-4-EN-20-YN-3-ONE 17-ACETYLOXY-(17-a)-19-NORPREGN-4-ESTREN-17-P-OL-ACETATE-3-ONE 17-ENT 17-a-ETHINYL-19-NORTEST-OSTERONE ACETATE 17-a-ETHINYL-19-NORTESTOSTERONE-17-P-ACETATE 17-a-ETHYNYL-17-P-ACETOXY-19-NORANDROST-4-EN-3-ONE 17-a-ETHYNYL-17-HYDROXYESTR-4-EN-3-ONE ACETATE 17-a-ETHYNYL-19-NORTESTO-STERONE ACETATE 17-HYDROXY-19-NOR-17-a-PREGN-4-EN-20-YN-3-ONE ACETATE 17-P-HYDROXY-19-NOR-17-a-PREGN-4-EN-20-YN-3-ONE ACETATE NORETHINDRONE-17-ACETATE 19-NORETHISTERONE ACETATE 19-NORETHYNYLTESTOSTERONE ACETATE NORETHYSTERONE ACETATE NORLUTATE NORLUTINE ACETATE ORLUTATE... 

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