Effects of estradiol decanoate in ovariectomized women

Pharmacokinetic evaluation of oral 17 beta-oestradiol and two different fat soluble analogues in ovariectomized women

A randomised, single-blind comparative study was carried out in 9 ovariectomized women to evaluate the kinetics of single doses of three different steroid combinations: 0.150 mg desogestrel + 2.0 mg micronized 17 beta-oestradiol, 0.150 mg desogestrel + 0.500 mg 17 beta-oestradiol cyclo-octyl acetate and 0.150 mg desogestrel + 1.0 mg 17 beta-oestradiol decanoate. Serum levels of 17 beta-oestradiol and oestrone were measured, as well as the excretion of 17 beta-oestradiol and its metabolites (oestrone and oestriol) in urine. In relation to the doses given, higher peak serum concentrations of 17 beta-oestradiol were obtained after the two fat soluble analogues, while the AUCs were similar to that after micronised 17 beta-oestradiol. However, there was more extensive conversion of the micronised 17 beta-oestradiol preparation into oestrone compared to 17 beta-oestradiol cyclo-octyl acetate and 17 beta-oestradiol decanoate. The oestrone/17 beta-oestradiol serum concentration ratio was approximately 2.6 before tablet intake and remained essentially unchanged after intake of 17 beta-oestradiol cyclo-octyl acetate and 17 beta-oestradiol decanoate. After micronized 17 beta-oestradiol however, there was a 2-3-fold increase in the ratio at Cmax and slower elimination of 17 beta-oestradiol from plasma, which may be due to the fact that high serum oestrone levels may serve as a reservoir, since both a metabolite and also a precursor of 17 beta-oestradiol. The urinary excretion of 17 beta-oestradiol, oestrone and oestriol was highest after oral administration of micronized 17 beta-oestradiol compared to 17 beta-oestradiol cyclo-octyl acetate and 17 beta-oestradiol decanoate.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral versus vaginal absorption in oestradiol in postmenopausal women. Effects of different particles sizes

Crystalline oestradiol-17 beta is poorly absorbed from the gastrointestinal tract. Three different fractions and a standard fraction containing oestradiol- 17 beta of a known particle size and surface area, were administered orally, to postmenopausal women, to test if changes in particle size will influence the absorption. The bioavailability of each fraction was determined by measurements of peripheral plasma oestrogens. Two different dosages of the standard fraction were given vaginally to compare the bioavailability after oral and vaginal administration. The gastrointestinal absorption was dependent of the particle size of oestradiol. The smaller particle the more rapid and effective absorption as reflected by increasing area under the plasma concentration curve of oestrone and oestradiol. The smallest particle, however, resulted in a pronounced initial oestradiol peak. The coarser particles were more slowly absorbed with more even plasma oestrogen elevation for a sustained period of time. The vaginal absorption of oestradiol was more effective than the gastrointestinal. When the same amount of an equal preparation according to particle size, was given vaginally the maximal plasma concentration was almost 40 times higher than when given orally.

Plasma concentrations of unconjugated and conjugated estrogens and gonadotrophins following application of various estrogen preparations after oophorectomy and in the menopause

In 55 patients after oophorectomy and 20 women after natural menopause an oral estrogen replacement therapy was performed with estrone-sulfate, estradiol 17-valerate, estriol-succinate, a combination of micronized estradiol and estriol (Estrifam, Trisequens), and natural conjugated estrogens. In 4 patients a 3 mg estradiol per 5 g ointment substance was applied on the abdominal skin. The interindividual variations of estrogen increments during therapy were considerably high. Oral intake of 2 mg estriol-succinate daily was followed by a 500% increase of total (conjugated + unconjugated) estriol. Concentrations of unconjugated estrogens were not altered by this dosage. Following oral application of the other above mentioned preparations, prominent rises--especially of unconjugated estrogens in plasma--were noted. The concentration peaks occurred within 3--6 h after application. Unconjugated estradiol-17 beta in plasma was comparable with values of the follicular phase of a normal menstrual cycle, unconjugated estrone, however, was nonphysiologically high. Consequently, the E1/E2 ratio was greater than one whereas it is normally below one. 12 h after oral estrogen application, plasma estrogens dropped to almost initial values, so that a second medication seems to be necessary in order to guarantee an adequate supplementation over the course of the day. The hormone values determined in this study did not show significant differences between patients after a natural menopause and after oophorectomy. There was a positive correlation between rising estrogen levels and suppressed gonadotrophins during replacement therapy. The occurrence of climacteric symptoms did not exclusively depend on low estrogen and high gonadotrophin levels. Good tolerance of estrogen therapy with significantly elevated estrogen concentrations in plasma can be obtained transcutaneously in the form of estrogen ointments. Such therapy might simulate the physiological estrogen pattern even better than oral application does because of delayed and diluted steroid flow to the liver.

Circulating prolactin and its response to TRH following administration of testosterone undecanoate in normal men

To investigate the effect of orally administered testosterone undercanoate (TU) on circulating prolactin (PRL) and PRL response to TRH stimulation, 8 eugonadal male volunteers, aged 19--30, presenting with normal plasma levels of FSH, LH, testosterone (T), estradiol (E2) and PRL, were given 120 mg/day of TU for 6 days. Plasma PRL levels were measured daily during the pre-treatment phase (3 days), treatment phase (6 days) and post-treatment phase (3 days) by radioimmunoassay. The TRH Test (200 micrograms iv) was done on the 3rd day of the pretreatment phase and on the treatment phase. No significant changes in circulating PRL levels or in PRL response to TRH stimulation were observed. Plasma T and E2 levels showed a slight, but not significant tendency to increase, while gonadotropin levels remained unchanged.