Medicine and Pharmacology Essay Example | Topics and Well Written Essays - 4750 words

Medicine and Pharmacology - Essay Example Mefloquine HCl is available as 250-mg tablets (equivalent to 228.0 mg of the free base). The presence of food significantly enhances the rate and extent of absorption. About 98% of the drug binds to protein. Mefloquine is excreted mainly in the bile and feces; therefore, no dose adjustment is needed in persons with renal insufficiency. The drug and its main metabolite are not appreciably removed by hemodialysis. No special chemoprophylactic dosage adjustments are indicated for dialysis patients to achieve plasma concentrations similar to those in healthy persons. Pharmacokinetic differences have been detected between various ethnic populations. In practice, however, these are of minor importance compared with host immune status and parasite sensitivity. In patients with impaired liver function, the elimination of mefloquine may be prolonged, leading to higher plasma levels (U.S.A Food and Drug Administration Guide for Larium 2003). Mefloquine should be used with caution in individuals participating in activities requiring alertness and fine-motor coordination e.g., driving, piloting aircraft, operating machinery, and deep-sea diving. If the drug is to be administered for a prolonged period, periodic evaluations are recommended, including liver function tests and ophthalmic examinations. Sleep abnormalities such as insomnia, abnormal dreams have occasionally been reported. Psychosis and seizures occur rarely; mefloquine should not be prescribed to patients with neuropsychiatric conditions, including depression, generalized anxiety disorder, psychosis, schizophrenia, and seizure disorder. If acute anxiety, depression, restlessness, or confusion develops during prophylaxis, these psychiatric symptoms may be considered prodromal to a more serious event, and the drug should be discontinued (Weinke et al., 1991) Importance of the drug and relevance to the topic Mefloquine given 250 mg of salt weekly in an adult dose has been the antimalarial prophylactic agent of choice for much of the tropics because it is usually effective against multidrug-resistant falciparum malaria and is reasonably well tolerated. Mild nausea, dizziness, fuzzy thinking, disturbed sleep patterns, vivid dreams, and malaise are relatively common. Although rare, due to its potential increased use, the occurrences of neuropsychiatric side effects have come into attention. Approximately 1 in every 10,000 recipients develops an acute reversible neuropsychiatric reaction manifested by confusion, psychosis, convulsions, or encephalopathy. Therefore questions arise whether this should be used. This is a debatable issue, and it would be worthwhile to find out research evidence on this topic (Steffen et al., 1993). Review of Literature Mefloquine is the most effective medicine in the prophylaxis and treatment of malaria. However, neuropsychiatric side-effects can more often be seen with the use of mefloquine compared to other anti-malaria drugs. Murai et al. (2005) studied the neuropsychiatric symptoms caused by mefloquine on report from several cases. After analysis of the data the authors assume, that besides the