الفهرس 
Dosage and administrationOnly 14 pages are availabe for public view
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Abstract
Raloxifene Hcl (RHL) is a selective estrogen receptor modulator drug. It has estrogen agonist effects on bone and cholesterol metabolism but behaves as a complete estrogen antagonist on uterine and breast tissue. It can reduce the risk of spinal fractures with high potential of reducing the risk of invasive breast cancer in postmenopausal women with osteoporosis. In humans, after oral administration the absorption of raloxifene occurs rapidly and approximately 60 % of dose was absorbed. Although RLX is characterized by high permeability, its absolute bioavailability is only 2%. Therefore RLX pertains to class II of the Biopharmaceutical Classification System, where the drugs are highly permeable but poorly soluble. This means that the oral bioavailability of raloxifene is dissolution rate limited. In addition, raloxifene suffers from extensive presystemic metabolism which is dominated by glucuronidation in the intestine and liver. This combined effect of poor dissolution and extensive fist pass metabolism leads to a very low bioavailability (2.6 ± 0.4 %). Accordingly, enhancing the drug dissolution is expected to increase the oral bioavailability of it. The benefit will become even greater if the selected excipients and/or dissolution enhancement technique can inhibit the presystemic metabolism.