The time of action of senna is usually 8–10 hours, and thus the dose should be taken at night ( 24 ). The action of the sennosides augments, without disrupting, the response to the physiological stimuli of food and physical activity ( 24 ). The sennosides abolish the severe constipation of patients suffering from severe irritable bowel syndrome ( 26 ). In therapeutic doses, the sennosides do not disrupt the usual pattern of defecation times and markedly soften the stool ( 24 ). Sennosides significantly increase the rate of colonic transit ( 27 ) and increase colonic peristalsis, which in turn increase both faecal weight and dry bacterial mass ( 24 , 28 ). Due to their colonic specificity, the sennosides are poorly absorbed in the upper gastrointestinal tract ( 29 ).
Glucocorticoids, particularly cortisol , promote the conversion of fats to carbohydrates and the deposition of glycogen (a storage form of glucose) in the liver and participate in maintaining normal blood-sugar concentrations. The production of glucocorticoids is regulated by adrenocorticotropic hormone , secreted by the pituitary gland . They also play a minor part in regulating the excretion of mineral salts and water, but the most powerful of the hormones exerting this mineralocorticoid effect is aldosterone: it controls sodium metabolism in mammals and promotes the excretion of magnesium in the urine.
In patients with severely impaired renal function or decreased urate clearance, the half-life of oxypurinol in the plasma is greatly prolonged. Patients should be treated with the lowest effective dose, in order to minimize possible side effects. The appropriate dose of allopurinol sodium for injection for patients with a creatinine clearance ≤10 mL/min is 100 mg per day. For patients with a creatinine clearance between 10 and 20 mL/min, a dose of 200 mg per day is recommended. With extreme renal impairment (creatinine clearance less than 3 mL/min), the interval between doses may also need to be extended.