Oestrogens pharmacokinetics

Howell A, DeFriend DJ, Robertson JF, Blarney RW, Anderson L, Anderson E, Sutcliffe FA, Walton P (1996) Pharmacokinetics, pharmacological and anti-tumour effects of the specific anti-oestrogen ICI 182780 in women with advanced breast cancer. Br J Cancer 74 300-308... 

Biochemical effects of the non-steroidal oestrogen 2,6-cis-diphenyl-hexamethyl-cyclotetrasiloxane (Cisobitan ) were also investigated in mans8. Pharmacokinetic and clinical studies have been performed at Radiumhemmet, Stockholm, in patients with poorly differentiated prostatic carcinoma. The pharmaceutical preparation was made as a soy bean oil solution in soft capsules containing 100 mg Cisobitan per capsule. 

Pedersen, P.C., Gerrits, M., Watson, N. and Bjarnason, K. (2002) Levormeloxifene safety, pharmacodynamics and pharmacokinetics in healthy postmenopausal women following single and multiple doses of a new selective oestrogen receptor modulator. British Journal of Clinical Pharmacology, 53, 284-295. 

Oral contraceptives increase diflunisal clearance in women, but only to the level normally seen in men. One study showed modestly reduced levels of ibuprofen with oral contraceptives, but another study did not. Oral contraceptives reduced the levels of aspirin, but not phenylbutazone. There are no clinically relevant changes in the pharmacokinetics of oxaprozin with conjugated oestrogens. 

There was no difference in the pharmacokinetics of a single 1.2-g dose of oxaprozin in 11 women taking conjugated oestrogens (Premarin) than in 11 control women, except that the time to peak concentration was shorter (4 versus 8.9 hours). This difference is unlikely to be of clinical importance. 

One study found that the pharmacokinetics of a single 650-mg intravenous dose of paracetamol did not differ between women who had taken conjugated oestrogens for at least 3 months and control subjects. ... 

A small study suggests that HRT treatment can almost double the serum levels of tacrine. Limited evidence suggests that oestrogens do not affect rivastigmine pharmacokinetics. 

In contrast, analysis of population data from 70 subjects found that oestrogens did not affect rivastigmine pharmacokinetics. ... 

Plo ltazone. The pharmacokinetics of ethinylestradiol and estrone were not affected when Premarin (conjugated oestrogens) 0.625 mg and Provera (medroxyprogesterone) 5 mg was given for 28 days, with pioglitazone 45 mg daily for an additional 14 days. ... 

Theoretically, the combination of an oestrogen antagonist such as tamoxifen and an aromatase inhibitor should provide additional benefit in the treatment of hormone-dependent cancers, however, no clinical studies have yet found this to be so. The pharmacokinetic interactions described above may partly explain this. It may be preferable to use these drugs sequentially rather than concurrently. ... 

Simonson SG, Martin PD, Warwick MJ, Mitchell PD, Schneck DW. The effect of rosuvastatin on oestrogen progestin pharmacokinetics in healthy women taking an oral contraceptive. Br J CUn Pharmacol (2004) 57, 279-86. 

Rad, M., M. Humpel, O. Schaefer, et al. 2006. Pharmacokinetics and systemic endocrine effects of the phyto-oestrogen 8-pre-nylnaringenin after single oral doses to postmenopausal women. Br. J. Clin. Pharmacol. 62(3) 288-296. 

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