Seizures mefloquine

Mefloquine (oral) 228 mg (base) (250 mg salt) weekly Less than or equal to 15 kg 4.6 mg/kg base (5 mg/kg salt) once weekly 1 5-19 kg 1/4 tablet 20-30 kg 1/f tablet 31-45 kg 3A tablet Greater than or equal to 45 kg 1 tablet Start 1 -2 wk before departure and continue for 4 wk after leaving endemic area may start 3—4 wk earlier to assess tolerance Contraindications History of seizure, psychiatric disorders (including depression and anxiety), or arrhythmias... 

Weekly dosing with mefloquine for chemoprophylaxis may cause nausea, vomiting, dizziness, sleep and behavioral disturbances, epigastric pain, diarrhea, abdominal pain, headache, rash, and dizziness. Neuropsychiatric toxicities have received a good deal of publicity, but despite frequent anecdotal reports of seizures and psychosis, a number of controlled studies have found the frequency of serious adverse effects from mefloquine to be no higher than that with other common antimalarial chemoprophylactic regimens. Leukocytosis, thrombocytopenia, and aminotransferase elevations have been reported. 

The latter adverse effects are more common with the higher dosages required for treatment. These effects may be lessened by administering the drug in two doses separated by 6-8 hours. The incidence of neuropsychiatric symptoms appears to be about ten times more common than with chemoprophylactic dosing, with widely varying frequencies of up to about 50% being reported. Serious neuropsychiatric toxicities (depression, confusion, acute psychosis, or seizures) have been reported in less than one in 1000 treatments, but some authorities believe that these toxicities are actually more common. Mefloquine can also alter cardiac conduction, and arrhythmias and bradycardia have been reported. 

ANTI EPILEPTICS 1. ANTIMALARIALS -chloroquine, mefloquine 2. ANTIDEPRESSANTS-MAOIs, SSRIs, TCAs 3. ANTIPSYCHOTICS t risk of seizures These drugs lower seizure threshold Care with co-administration. Watch for t fit frequency warn patient of this risk when starting these drugs and take suitable precautions. Consider increasing dose of antiepileptic... 

BUPROPION 1. ANTIBIOTICS - fluoroquinolones 2. ANTICANCER AND IMMUNO-MODULATING DRUGS-corticosteroids, interferons 3. ANTIDEPRESSANTS-TCAs 4. ANTIMALARIALS - chloroquine, mefloquine 5. ANTIPSYCHOTICS 6. BRONCHODILATORS -theophylline 7. CNS STIMULANTS 8. PARASYMPATHOMIMETICS T risk of seizures. This risk is marked in elderly people, in patients with a history of seizures, with addiction to opiates/cocaine/ stimulants, and in diabetics treated with oral hypoglycaemics or insulin Bupropion is associated with a dose-related risk of seizures. These drugs, which lower seizure threshold, are individually epileptogenic. Additive effects occur when combined Extreme caution. The dose of bupropion should not exceed 4S0 mg/day (or 150 mg/day in patients with severe hepatic cirrhosis)... 

CHLOROQUINE ANTIMALARIALS -MEFLOQUINE Risk of seizures Additive effect Warn patient of the risk patients should be advised to avoid driving while taking these drugs in combination... 

MEFLOQUINE ANTI EPILEPTICS 1 efficacy of antiepileptics Mefloquine can l seizure threshold Care with co-administration T dose of antiepileptic if T incidence of fits... 

Adverse effects include nausea, dizziness, disturbance of balance, vomiting, abdominal pain, diarrhoea and loss of appetite. More rarely, hallucinations, seizures and psychoses occur. Mefloquine should be avoided in patients taking (i-adrenoceptor and calcium channel antagonists for it causes sinus bradycardia quinine can potentiate these and other... 

A 20-year-old woman with bilateral myoclonus and generalized tonic-clonic seizures which had been controlled with valproic acid was given 2 prophylactic doses of mefloquine and developed generalized tonic-clonic seizures. 

In P. falciparum (chloroquine-resistant) infections, a dose of 750 mg mefloquine followed by 500 mg 12 hours later is recommended. The pediatric dose of mefloquine is 15 mg/kg (<45 kg) followed by 10 mg/kg 8 to 12 hours later.Intravenous quinidine gluconate followed by oral quinine should be administered for severe illness, as already indicated.A second drug needs to be administered in chloroquine-resistant P. falciparum, and this second drug should follow the oral quinidine regimen either a single dose of three tablets of pyrimethamine-sulfadoxine (Fansidar) on the last day of intravenous quinidine or clindamycin 900 mg three times daily for 3 to 5 days. An alternative oral treatment for chloroquine-resistant P falciparum infection in adults, especially in those with a history of seizures or psychiatric disorders, is the combination of atovaquone 250 mg and proguanil 100 mg (Malarone) (4 tablets daily... 

Mefloquine hydrochloride (lariam) is available for oral administration only. Tablets marketed in the U.S. contain 250 mg mefloquine hydrochloride, equivalent to 228 mg mefloquine base (this may vary in Canada and elsewhere). The dosing below is expressed in mg salt. Adults and children >45 kg body weight take 250 mg weekly starting 1-2 weeks before entering an endemic area and ending 4 weeks after leaving. Pediatric doses, taken by the same schedule, are 5 mg/kg for children up to 15 kg (may have to be prepared by a pharmacist) 62.5 mg (1/4 tablet) for 15-19 kg 125 mg (V2 tablet) for 20-30 kg 187.5 mg /k tablet) for 31 5 kg. Note Mefloquine is not recommended for children weighing <5 kg or individuals with a history of seizures, severe neuropsychiatric disturbances, sensitivity to quinoline antimalarials, or cardiac conduction abnormalities. 

Mefloquine NVD, dizziness, syncope, extrasystoles, CNS effects (rare) Avoid in seizures, psychiatric disorders, and cardiac conduction defects... 

Anti-infective drugs Ciprofloxacin can greatly increase the risk of seizure induction in patients taking anticonvulsants. Erythromycin produces a rapid 100-200% rise in carbamazepine levels. There is a possibility of reduced plasma levels of the protease inhibitors indinavir and saquinavir with carbamazepine. Isoniazid increases carbamazepine serum levels, and leads to the possible emergence of toxicity (disorientation and aggression). Mefloquine may antagonize the anticonvulsant effect of carbamazepine. Ritonavir, a protease inhibitor, may cause toxicity by raising carbamazepine plasma levels. 

Toxicity Mefloquine is less toxic than quinine its adverse effects include gastrointestinal distress, skin rash, headache, and dizziness. At high doses, mefloquine may cause neurologic symptoms and seizures. 

The incidence of side effects with mefloquine is considered to be high. The effects are classified as neuropsychiatric, Gl, dermatologic, and cardiovascular. The neuropsychiatric effects may be serious (e.g., suicidal tendencies or seizures) or minor (e.g., dizziness, vertigo, ataxia, and headaches). Gastrointestinal side effects included nausea, vomiting, and diarrhea, whereas the dermatologic effects include rash, pruritus, and urticaria. Finally, cardiovascular side effects may include bradycardia, arrhythmias, and extrasystoles. 

An isolated report deseribes a 20-year-old woman, with a 7-year history of epilepsy (bilateral myoelonus and generalised tonic-clonic seizures) controlled with sodium valproate 1.3 g daily, who developed tonic-clonic seizures 8 hours after taking the second of 3 prophylactic doses of mefloquine 250 mg. It is not clear whether this resulted from a drug-drug or a drug-disease interaction. The manufacturers of mefloquine advise its avoidance in those with a history of convulsions as it may increase the risk of convulsions. In these patients mefloquine should he used only for curative treatment if compelling reasons exist. ... 

It has been hypothesized that the mechanisms whereby mefloquine increases the risk of seizures in patients with a history of seizures, which may be via altered neuronal calcium homeostasis, altered gap-junction functioning, and neuronal cell death, are particularly associated with a mutation in EPMl, a gene that is associated with progressive myoclonic epilepsy type 1, and hence altered GABA activity [10 ]. The author proposed that mefloquine should be contraindicated in people with the EPMl mutation and in those with a history of myoclonus or ataxia, or a family history of degenerative neurological disorders that are consistent with the presence of the EPMl mutation. 

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