rn INDICATIONS: UTROGESTAN is indicated as replacement therapy or peri menopause has also been used in the premenstrual syndrome, dysfunctional uterine bleeding, in high sterility and luteal insufficiency, benign breast disease and threatened abortion. Pharmacokinetics: Approximately 60% of an oral dose is absorbed UTROGESTAN intestine. Subsequently liver these substances are partially metabolized. Peak plasma levels are achieved after one to four hours. There are interindividual differences, but these differences appear to be minor. Please consult your physician before taking any medication. The bioavailability (defined as the area under the curve) is linear and is dose related. The major metabolites in plasma are the biologically active 20 a-dihydroxyprogesterone and inactive where pregnanediol predominates. Most of progesterone and its metabolites, which have reached the systemic circulation, they are excreted by the kidneys, mainly as metabolites glucuroneos pregnanediol and pregnenolone. The second major route of excretion is the bile and feces. Mechanisms of Action: There is a general agreement that progesterone exerts its main biological effects through specific intracellular uptake of protein called a receptor. Today it is known that after administration of progesterone, the hormone-receptor complex migrates towards the edge of the condensed chromatin and chromatin also dispersed. The main explanation why certain progesterone has anti-estrogenic effects, at least in the endometrium and the breast is by the specificity of progesterone on the uptake of various proteins. Absorption: For many years it was accepted that progesterone administered parenterally since the oral administration was influenced by the absorption and rapid hepatic activation. After administration of UTROGESTAN peak plasma levels are reached approximately one to four hours. In the bloodstream progesterone is bound to plasma proteins. The half-life of plasma progesterone after oral dose is approximately 24 hours.