Absorption of Estrogens from Vaginal Creams

The Influence of Topical Vaginal Estrogen Application on the Lipids Metabolism

“…According to Rigg et al [13], following vaginal administration the blood estradiol level rises significantly after 15-30 min. In their opinion the biological effect of estrogen cream is immediate through delivery to the target organ by circulation.…”

“…In their reviews, several authors like Rigg et al [13], Eglund and Johansson [2], Horwitz and Feinstein [5], Martin et al [10] and Schiff et al [ 14] demonstrated that estrogens administered vaginally were well absorbed into the circulation. In the article of DiRaimondo et al [1] the authors go as far as relating the appearance of gynecomastia in the husband of one patient due to the use of topical estrogen by his wife.…”

Rectal and Vaginal Absorption of Peptides and Proteins

“…Reduced first-pass effects after vaginal application of estrogens (Rigg et al, 1978) and propranolol (Patel et al, 1983) have been reported. Recently, comparative studies on the peptidase activity against enkephalins, substance P, insulin, and proinsulin in the absorptive mucous membranes in the rabbit have demonstrated that the supernatants of homogenates of the vaginal, nasal, buccal, rectal, and ileal mucous membranes exhibit similar proteolytic activity (Lee, 1988;Lee and Yamamoto, 1990).…”

Hormone Replacement Therapy

“…For instance, as described on page 839 by Hutton and his colleagues, when oestradiol is ingested the gut itself oxidizes it to oestrone, so plasma concentrations of oestrone and oestradiol are similar whether the women are treated with a preparation based on oestrone or on oestradiol. Curiously the vaginal epithelium lacks the necessary enzymes to effect this conversion and so when oestradiol is put directly into the vagina, plasma oestradiol concentrations are much higher than they are when it is given by mouth (Rigg et al 1978). This apparently obscure comer of biochemistry has important clinical consequences because it means that contraindications to systemic oestrogen therapy are now contraindications to local therapy too .…”