However, they also noted that the importance of the activities requires further study in animal models at pharmacologically relevant doses.DES has been identified as an antagonist of all three isotypes of the estrogen-related receptors (ERRs), the ERRα, ERRβ, and ERRγ. Half-maximal inhibition occurs at a concentration of about 1 μM. Pharmacokinetics
DES is well-absorbed with oral administration. With an oral dosage of 1 mg/day DES, plasma levels of DES at 20 hours following the last dose ranged between 0.9 and 1.9 ng/mL (3.4 to 7.1 nmol/L). Sublingual administration of DES appears to have about the same estrogenic potency of oral DES in women. Intrauterine DES has been studied for the treatment of uterine hypoplasia. Oral DES is thought to have about 17 to 50% of the clinical estrogenic potency of DES by injection.The distribution half-life of DES is 80 minutes. It has no affinity for SHBG or corticosteroid-binding globulin, and hence is not bound to these proteins in the circulation. The plasma protein binding of DES is greater than 95%.Hydroxylation of the aromatic rings of DES and subsequent conjugation of the ethyl side chains accounts for 80 to 90% of DES metabolism, while oxidation accounts for the remaining 10 to 20% and is dominated by conjugation reactions. Conjugation of DES consists of glucuronidation, while oxidation includes dehydrogenation into (Z,Z)-dienestrol. The medication is also known to produce paroxypropione as a metabolite. DES produces transient quinone-like reactive intermediates that cause cellular and genetic damage, which may help to explain the known carcinogenic effects of DES in humans.
Circulating carboxy-terminal fragments are filtered by the kidney, but are subsequently broken down into even smaller fragments during tubular reuptake. No studies have so far been performed in patients with severe hepatic impairment. The pharmacokinetics of parathyroid hormone in patients with severe chronic kidney disease (creatinine clearance of less than 30 ml/min) has not been investigated either. Pharmaceutical particulars
Preotact is delivered in a two chamber, glass ampoule. One chamber contains the active substance in the form of a white powder (with excipients: mannitol, citric acid monohydrate, NaCl, NaOH, HCl). And the other contains the solvent; water for injection. The powder is mixed with the solvent when the ampoule is inserted into the injection device. Storage and shelf-life
The mixed solution is stable for 28 days when stored between 2 and 8 °C. During this 28-day period the mixed solution may be stored for up to 7 days at room temperature, allowing the patient the freedom to travel. Unmixed ampoules have a shelf-life of 30 months. The products should not be frozen and should be protected from light. See also
Teriparatide, another parathyroid hormone

References
External links
"Parathyroid hormone". Drug Information Portal. U.S. National Library of Medicine.