ADJUVANT ANALGESICS: PROGESTOGENS AND NEUROLEPTICS
Sunday, June 19th, 2011The progestational agents, medroxyprogesterone acetate and megestrol acetate, are claimed to be of benefit in relieving the pain related to metastatic disease in patients with breast, prostate, endometrial and renal cancer. Progestogen therapy may have an antitumour action in some patients with these diseases, but the co-analgesic action is claimed to occur in a significantly larger proportion of the patients. The mechanism by which progestogens might exert this effect is unknown. The usual dose is 200-500 mg/d of medroxyprogesterone acetate or 160 mg/d of megestrol acetate. Side effects include nausea and vomiting, fluid retention leading to weight gain, oedema, cardiac failure and hypertension, and vaginal bleeding. Neuroleptic-The neuroleptic drugs such as chlorpromazine and haloperidol have no analgesic action but are of benefit in treating patients with pain by reducing anxiety and improving night-time sedation. However, unless specifically indicated for the treatment of delirium or nausea, the same benefits can be obtained with a benzodiazepine which will not have anticholinergic and extrapyramidal side effects.*60\55\2*
