Mefloquine prophylaxis

Mefloquine prophylaxis can be undertaken v/ith caution in cardiac conduction disorders. It should be avoided in epilepsy, during pregnancy and breastfeeding and for 3 months after pregnancy. 

A 52-year-old woman with no psychiatric history developed anxiety, paranoia, visual hallucinations, confusion, and depressive symptoms after 3 doses of prophylactic mefloquine (250 mg/week) (502). She had previously taken mefloquine prophylaxis intermittently for 4 years with no adverse events. 

Raised transaminases (up to 20 times normal activities) have been seen in a man taking mefloquine prophylaxis they resolved after withdrawal of mefloquine (35). 

Tangkitchot S, Boudreau E, Bunnag D, White NJ. Mefloquine prophylaxis prevents malaria during pregnancy a double-blind, placebo-controlled study. J Infect Dis 1994 169(3) 595-603. 

The levels of Iumefantrine were modestly reduced by mefloquine pretreatment, but the levels of artemether and of mefloquine were not affected. No adverse effects on the QT interval were seen. These data indicate that co-artemether may be used after mefloquine prophylaxis or treatment. 

In another study, similar sequential use of these drugs did not affect the QT interval, and drug levels were also considered adequate for treatment. The authors considered that adverse effects on the QT interval are unlikely to occur if co-artemether is used after mefloquine prophylaxis or treatment. 

The recently introduced antimalanal halofantrine (6) is an orally active blood schizonucide reported to be more than 95% effective in the treatment of malaria [S] Mefloquine hydrochloride (7) contmues to be useful m the prophylaxis and treatment of malaria [9]... 

Q56 When dispensing mefloquine as a prophylaxis against malaria, the patient should be advised that ... 

Patients taking mefloquine as prophylaxis against malaria should be advised to take the medication regularly and to avoid mosquito bites. Dizziness may be caused by mefloquine and patients should be informed about this side-effect. 

Antimalarial drugs are designed to prevent or treat malaria. Antimalarial drugs currently used for treatment for prophylaxis are mefloquine, primaquine, chloroquine, pyrimethamine, amodiaquin, quinine/quinidine, chloroguanide. 

III. Quinoline-methanol derivatives Mefloquine (MEFLOC) 15 mg/kg single dose (for treatment, maximum 1 g) 5 mg/kg, up to 250 mg per wk (for prophylaxis in areas with multidrug resistance)... 

Mefloquine is effective in prophylaxis against most strains of P falciparum and probably all other human malarial species. Mefloquine is therefore among the drugs recommended by the CDC for chemoprophylaxis in all malarious areas except for those with no chloroquine resistance (where chloroquine is preferred) and some rural areas of Southeast Asia with a high prevalence of mefloquine resistance. As with chloroquine, eradication of P vivax and P ovale requires a course of primaquine. 

Clinical Use. Mefloquine (Lariam) has emerged as one of the most important antimalarial agents.61 This drug is especially important in the prevention and treatment of malaria that is resistant to traditional antimalarial drugs such as chloroquine and quinine.50 Mefloquine is often the drug of choice for antimalarial prophylaxis, especially in areas of the world where chloroquine-resistant strains of malaria are common.23 Mefloquine can be used alone, but combining this... 

A 48-year-old woman developed anxiety, tremor, depression, dry mouth, nausea, and marked weight loss (503). Physical examination, electrocardiography, chest X-ray, CT scan, and laboratory investigations were unremarkable. The Hamilton D score was 44 for 17 items. She had taken mefloquine 250 mg/week for 8 weeks for malaria prophylaxis, and after 2 weeks had started to feel unwell, with dysphoria, depression, and weakness. She was given fluoxetine 20 mg/day and alprazolam 1.5 mg/day. Her condition continued to deteriorate. The dose of fluoxetine was increased to 40 mg/day and flunitrazepam was added. She was later instead given milnacipran, a serotonin and noradrenaline reuptake... 

A postal survey of the incidence of psychiatric disturbances in 2500 returning Israeli travellers (505) showed that travellers with this class of adverse effects were more likely to have taken mefloquine than other antimalarial drugs. Of 117 travellers with psychiatric adverse effects, 115 had taken mefloquine compared with 948/1340 for the entire cohort. This was a retrospective postal study with a response rate of 54% (1340 out of 2500), and of those who responded 71% had taken mefloquine, 5% had taken chloroquine, and 24% had taken no prophylaxis. In this study 11% (117) of the respondents reported psychiatric disturbances, mainly sleep disturbance, fatigue, vivid dreams, or lack of mood. Only 16 of the respondents had symptoms lasting 2 months or more. Those who had had a psychiatric disturbance were also more likely to have been female and to have taken recreational drug use. 

After 4 weeks of malaria prophylaxis with mefloquine 250 mg/week, a 25-year-old woman developed bizarre... 

In a review of 10 trials (n = 2750 non-immune adult travelers) (512) the effects of mefloquine in adult travellers were compared with the effects of other regimens in relation to episodes of malaria, withdrawal from prophylaxis, and adverse effects. Five trials were field studies of male soldiers. One comparison of mefloquine with placebo showed that mefloquine was effective in an area of drug resistance (OR = 0.04 95% Cl = 0.02, 0.08) and withdrawals in the mefloquine group were consistently higher in four placebo-controlled trials (OR = 3.56 95% Cl = 1.67, 7.60). 

Airline pilots should not take routine prophylaxis with mefloquine because of the small risk of neuropsychiatric reactions. 

Unfortunately, many persons experience extreme side effects from antimalarial medications. Further, chloroquine-resistant strains of falciparum malaria are on the increase worldwide. For this resistant parasite, the drug mefloquine is the preferred method of prophylaxis and treatment, although resistance to this drug may emerge rapidly, and resistant strains have been found in areas where the drug has never been used. 

Mefloquine, chloroquine, proguanil, and pyrimethamine plus dapsone (Maloprim), alone or in combination are most commonly advised for prophylaxis regimens and doxycycline for special cases (drug resistance or intolerance) primaquine is being re-evaluated. 

Mefloquine (t) 21 d) is similar in several respects to quinine although it does not intercalate with plasmodial DNA. It is used for malaria chemoprophylaxis, to treat uncomplicated Plasmodium falciparum (both chloroquine-sensitive and chloroquine resistant) and chloroquine-resistant Plasmodium vivax malaria. Mefloquine is rapidly absorbed from the gastrointestinal tract and its action is terminated by metabolism. When used for prophylaxis, 250 mg (base)/week should be taken, commencing 1-3 weeks before entering and continued for 4 weeks after leaving a malarious area. It should not be given to patients with hepatic or renal impairment. 

The adverse effects of mefloquine have been extensively reviewed both for prophylaxis (when rare neuropsychiatric adverse effects make its use controversial) and in treatment doses, when it has been linked to an increased incidence of the postmalaria neurological syndrome. A retrospective review of 5120 Itahan soldiers showed an overall chemoprophylaxis curtailment rate of less than 1%, which was not significantly different from the combination of chloroquine and proguanil (11). A semi-systematic review also suggested no significant difference in tolerabihty compared with other antimalarial drugs (12). 

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