CLINORIL (Sulindac) should be administered orally twice a day with food. The maximum dosage is 400 mg per day. Dosages above 400 mg per day are not recommended. In osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis, the recommended starting dosage is 150 mg twice a day. The dosage may be lowered or raised depending on the response.

Fresh rat liver was minced and then homogenized using 5 strokes in a Potter-Elvehjem homogenizer with 3 volumes of 50 mM Tris-Cl, pH 7.4. The homogenate was centrifuged for 15 min at 10,000g, the pellet was discarded, and the supernatant was spun at 100,000g for 2 h to obtain crude microsomes. The microsomes were washed by resuspension in 3 volumes of the above buffer and centrifugation at 100,000g for 1 h. The microsomal pellet was finally resuspended in 3 volumes of the above buffer, aliquoted, and frozen at -80°C. The protein concentration was 25 mg/ml. In a total volume of 100 mkl, 20 nmol of each sulindac epimer were incubated with 20 to 80 mkg of microsomes and a NADPH-regenerating system (1.5 mM NADPH, 5 mM glucose 6-phosphate, 150 ng of glucose-6-phosphate dehydrogenase, and 5 mM MgCl2) in potassium phosphate buffer (pH 7.4, 100 mM) for 60 min at 37°C. The reaction was then stopped with 3 volumes of acetonitrile and centrifuged. The supernatant was fractionated by HPLC as described above.