mefloquine hydrochloride (Mefloquine Hydrochloride) tablet
[Roxane Laboratories, Inc.]
Mefloquine hydrochloride is an antimalarial agent available as 250 mg tablets of mefloquine hydrochloride (equivalent to 228 mg of the free base) for oral administration.
Mefloquine hydrochloride is a 4-quinolinemethanol derivative with the specific chemical name of (R*,S*)-(±)-α-2- piperidinyI-2,8-bis(trifluoromethyl)-4-quinolinemethanoI hydrochloride. It is a 2-aryl substituted chemical structural analog of quinine. The drug is a white to almost white crystalline compound, slightly soluble in water.
Mefloquine hydrochloride has a calculated molecular weight of 414.78 and the following structural formula:
The inactive ingredients are calcium-ammonium alginate, colloidal silicon dioxide, crospovidone, lactose (regular), magnesium stearate, microcrystalline cellulose, poloxamer 331, povidone, and starch.
The absolute oral bioavailability of mefloquine has not been determined since an intravenous formulation is not available. The bioavailability of the tablet formation compared with an oral solution was over 85%. The presence of food significantly enhances the rate and extent of absorption, leading to about a 40% increase in bioavailability. In healthy volunteers, plasma concentrations peak 6 to 24 hours (median, about 17 hours) after a single dose of mefloquine. In a similar group of volunteers, maximum plasma concentrations in mcg/L are roughly equivalent to the dose in milligrams (for example, a single 1000 mg dose produces a maximum concentration of about 1000 mcg/L). In healthy volunteers, a dose of 250 mg once weekly, produces maximum steady-state plasma concentrations of 1000 to 2000 mcg/L, which are reached after 7 to 10 weeks.
In healthy adults, the apparent volume of distribution is approximately 20 L/kg, indicating extensive tissue distribution. Mefloquine may accumulate in parasitized erythrocytes. Experiments conducted in vitro with human blood using concentrations between 50 and 1000 mg/mL showed a relatively constant erythrocyte-to-plasma concentration ratio of about 2 to 1. The equilibrium reached in less than 30 minutes, was found to be reversible. Protein binding is about 98%.
Mefloquine crosses the placenta. Excretion into breast milk appears to be minimal (see PRECAUTIONS: Nursing Mothers).
Two metabolites have been identified in humans. The main metabolite, 2,8-bis-trifluoromethyl-4-quinoline carboxylic acid, is inactive in Plasmodium falciparum. In a study in healthy volunteers, the carboxylic acid metabolite appeared in plasma 2 to 4 hours after a single oral dose. Maximum plasma concentrations, which were about 50% higher than those of mefloquine, were reached after 2 weeks. Thereafter, plasma levels of the main metabolite and mefloquine declined at a similar rate. The area under the plasma concentration-time curve (AUC) of the main metabolite was 3 to 5 times larger than that of the parent drug. The other metabolite, an alcohol, was present in minute quantities only.
In several studies in healthy adults, the mean elimination half-life of mefloquine varied between 2 and 4 weeks, with an average of about 3 weeks. Total clearance, which is essentially hepatic, is in the order of 30 mL/min. There is evidence that mefloquine is excreted mainly in the bile and feces. In volunteers, urinary excretion of unchanged mefloquine and its main metabolite under steady-state condition accounted for about 9% and 4% of the dose, respectively. Concentrations of other metabolites could not be measured in the urine.
No relevant age-related changes have been observed in the pharmacokinetics of mefloquine. Therefore, the dosage for children has been extrapolated from the recommended adult dose.
No pharmacokinetic studies have been performed in patients with renal insufficiency since only a small proportion of the drug is eliminated renally. Mefloquine and its main metabolite are not appreciably removed by hemodialysis. No special chemoprophylactic dosage adjustments are indicated for dialysis patients to achieve concentrations in plasma similar to those in healthy persons.
Although clearance of mefloquine may increase in late pregnancy, in general, pregnancy has no clinically relevant effect on the pharmacokinetics of mefloquine.
The pharmacokinetics of mefloquine may be altered in acute malaria.
Pharmacokinetic differences have been observed between various ethnic populations. In practice, however, these are of minor importance compared with host immune status and sensitivity of the parasite.
During long-term prophylaxis (>2 years), the trough concentrations and the elimination half-life of mefloquine were similar to those obtained in the same population after 6 months of drug use, which is when they reached steady state.
In vitro and in vivo studies showed no hemolysis associated with glucose-6-phosphate dehydrogenase deficiency (see ANIMAL TOXICOLOGY).
Mefloquine is an antimalarial agent which acts as a blood schizonticide. Its exact mechanism of action is not known.
Mefloquine is active against the erythrocytic stages of Plasmodium species (see INDICATIONS AND USAGE). However, the drug has no effect against the exoerythrocytic (hepatic) stages of the parasite. Mefloquine is effective against malaria parasites resistant to chloroquine (see INDICATIONS AND USAGE).
Strains of P. falciparum with decreased susceptibility to mefloquine can be selected in vitro or in vivo. Resistance of P. falciparum to mefloquine has been reported in areas of multi-drug resistance in South East Asia. Increased incidences of resistance have also been reported in other parts of the world.
Cross-resistance between mefloquine and halofantrine and cross-resistance between mefloquine and quinine have been observed in some regions.
Mefloquine Hydrochloride Tablets are indicated for the treatment of mild to moderate acute malaria caused by mefloquine-susceptible strains of P. falciparum (both chloroquine-susceptible and resistant strains) or by Plasmodiumvivax. There are insufficient clinical data to document the effect of mefloquine in malaria caused by P. ovale or P. malariae.
Note: Patients with acute P. vivax malaria, treated with mefloquine, are at high risk of relapse because mefloquine does not eliminate exoerythrocytic (hepatic phase) parasites. To avoid relapse, after initial treatment of the acute infection with mefloquine, patients should subsequently be treated with an 8-aminoquinoline derivative (eg, primaquine).
Mefloquine Hydrochloride Tablets are indicated for the prophylaxis of P. falciparum and P. vivax malaria infections, including prophylaxis of chloroquine-resistant strains of P. falciparum.
Use of Mefloquine Hydrochloride Tablets is contraindicated in patients with a known hypersensitivity to mefloquine or related compounds (eg, quinine and quinidine) or to any of the excipients contained in the formulation. Mefloquine Hydrochloride Tablets should not be prescribed for prophylaxis in patients with active depression, a recent history of depression, generalized anxiety disorder, psychosis, or schizophrenia or other major psychiatric disorders, or with a history of convulsions.
In case of Iife-threatening, serious or overwhelming malaria infections due to P. falciparum, patients should be treated with an intravenous antimalarial drug. Following completion of intravenous treatment, mefloquine may be given to complete the course of therapy.
Data on the use of halofantrine subsequent to administration of mefloquine suggest a significant, potentially fatal prolongation of the QTc interval of the ECG. Therefore, halofantrine must not be given simultaneously with or subsequent to mefloquine. No data are available on the use of mefloquine after halofantrine (see PRECAUTIONS: Drug Interactions).
Mefloquine may cause psychiatric symptoms in a number of patients, ranging from anxiety, paranoia, and depression to hallucinations and psychotic behavior. On occasions, these symptoms have been reported to continue long after mefloquine has been stopped. Rare cases of suicidal ideation and suicide have been reported though no relationship to drug administration has been confirmed. To minimize the chances of these adverse events, mefloquine should not be taken for prophylaxis in patients with active depression or with a recent history of depression, generalized anxiety disorder, psychosis, or schizophrenia or other major psychiatric disorders. Mefloquine should be used with caution in patients with a previous history of depression.
During prophylactic use, if psychiatric symptoms such as acute anxiety, depression, restlessness or confusion occur, these may be considered prodromal to a more serious event. In these cases, the drug must be discontinued and an alternative medication should be substituted.
Concomitant administration of mefloquine and quinine or quinidine may produce electrocardiographic abnormalities.
Concomitant administration of mefloquine and quinine or chloroquine may increase the risk of convulsions.
Hypersensitivity reactions ranging from mild cutaneous events to anaphylaxis cannot be predicted.
In patients with epilepsy, mefloquine may increase the risk of convulsions. The drug should therefore be prescribed only for curative treatment in such patients and only if there are compelling medical reasons for its use (see PRECAUTIONS: Drug Interactions).
Caution should be exercised with regard to activities requiring alertness and fine motor coordination such as driving, piloting aircraft, operating machinery, and deep-sea diving, as dizziness, a loss of balance, or other disorders of the central or peripheral nervous system have been reported during and following the use of mefloquine. These effects may occur after therapy is discontinued due to the long half-life of the drug. Mefloquine should be used with caution in patients with psychiatric disturbances because mefloquine use has been associated with emotional disturbances (see ADVERSE REACTIONS).
In patients with impaired liver function the elimination of mefloquine may be prolonged, leading to higher plasma levels.
This drug has been administered for longer than 1 year. If the drug is to be administered for a prolonged period, periodic evaluations including liver function tests should be performed. Although retinal abnormalities seen in humans with long-term chloroquine use have not been observed with mefloquine use, long-term feeding of mefloquine to rats resulted in dose-related ocular lesions (retinal degeneration, retinal edema and lenticular opacity at 12.5 mg/kg/day and higher) (see ANIMAL TOXICOLOGY). Therefore, periodic ophthalmic examinations are recommended.
Parenteral studies in animals show that mefloquine, a myocardial depressant, possesses 20% of the antifibrillatory action of quinidine and produces 50% of the increase in the PR interval reported with quinine. The effect of mefloquine on the compromised cardiovascular system has not been evaluated. However, transitory and clinically silent ECG alterations have been reported during the use of mefloquine. Alterations included sinus bradycardia, sinus arrhythmia, first degree AV-block, proIongation of the QTc interval and abnormal T waves (see also cardiovascular effects under PRECAUTIONS: Drug Interactions and ADVERSE REACTIONS). The benefits of mefloquine therapy should be weighed against the possibility of adverse effects in patients with cardiac disease.
Periodic evaluation of hepatic function should be performed during prolonged prophylaxis.
Medication Guide: As required by law, a mefloquine Medication Guide is supplied to patients when mefloquine is dispensed. Patients should be instructed to read the MedGuide when mefloquine is received. The complete text of the MedGuide is reprinted at the end of this document.
Drug-drug interactions with mefloquine have not been explored in detail. There is one report of cardiopulmonary arrest, with full recovery, in a patient who was taking a beta blocker (propranolol) (see PRECAUTIONS: General). The effects of mefloquine on the compromised cardiovascular system have not been evaluated. The benefits of mefloquine therapy should be weighed against the possibility of adverse effects in patients with cardiac disease.
Because of the danger of a potentially fatal prolongation of the QTc interval, halofantrine must not be given simultaneously with or subsequent to mefloquine (see WARNINGS).
Concomitant administration of mefloquine and other related compounds (eg, quinine, quinidine and chloroquine) may produce electrocardiographic abnormalities and increase the risk of convulsions (see WARNINGS). If these drugs are to be used in the initial treatment of severe malaria, mefloquine administration should be delayed at least 12 hours after the last dose. There is evidence that the use of halofantrine after mefloquine causes a significant lengthening of the QTc interval. Clinically significant QTc prolongation has not been found with mefloquine alone.
This appears to be the only clinically relevant interaction of this kind with mefloquine, although theoretically, coadministration of other drugs known to alter cardiac conduction (eg, anti-arrhythmic or beta-adrenergic blocking agents, calcium channel blockers, antihistamines or H1-blocking agents, tricyclic antidepressants and phenothiazines) might also contribute to a prolongation of the QTc interval. There are no data that conclusively establish whether the concomitant administration of mefloquine and the above listed agents has an effect on cardiac function.
In patients taking an anticonvulsant (eg, valproic acid, carbamazepine, phenobarbital or phenytoin), the concomitant use of mefloquine may reduce seizure control by lowering the plasma levels of the anticonvulsant. Therefore, patients concurrently taking antiseizure medication and mefloquine should have the blood level of their antiseizure medication monitored and the dosage adjusted appropriately (see PRECAUTIONS: General).
When mefloquine is taken concurrently with oral live typhoid vaccines, attenuation of immunization cannot be excluded. Vaccinations with attenuated live bacteria should therefore be completed at least 3 days before the first dose of mefloquine.
No other drug interactions are known. Nevertheless, the effects of mefloquine on travelers receiving comedication, particularly diabetics or patients using anticoagulants, should be checked before departure.
In clinical trials, the concomitant administration of sulfadoxine and pyrimethamine did not alter the adverse reaction profile.
The carcinogenic potential of mefloquine was studied in rats and mice in 2-year feeding studies at doses of up to 30 mg/kg/day. No treatment-related increases in tumors of any type were noted.
The mutagenic potential of mefloquine was studied in a variety of assay systems including: Ames test, a host-mediated assay in mice, fluctuation tests and a mouse micronucleus assay. Several of these assays were performed with and without prior metabolic activation. In no instance was evidence obtained for the mutagenicity of mefloquine.
Fertility studies in rats at doses of 5, 20, and 50 mg/kg/day of mefloquine have demonstrated adverse effects on fertility in the male at the high dose of 50 mg/kg/day, and in the female at doses of 20 and 50 mg/kg/day. Histopathological lesions were noted in the epididymides from male rats at doses of 20 and 50 mg/kg/day. Administration of 250 mg/week of mefloquine (base) in adult males for 22 weeks failed to reveal any deleterious effects on human spermatozoa.
Mefloquine has been demonstrated to be teratogenic in rats and mice at a dose of 100 mg/kg/day. In rabbits, a high dose of 160 mg/kg/day was embryotoxic and teratogenic, and a dose of 80 mg/kg/day was teratogenic but not embryotoxic. There are no adequate and well-controlled studies in pregnant women. However, clinical experience with mefloquine has not revealed an embryotoxic or teratogenic effect. Mefloquine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Women of childbearing potential who are traveling to areas where malaria is endemic should be warned against becoming pregnant. Women of childbearing potential should also be advised to practice contraception during malaria prophylaxis with mefloquine and for up to 3 months thereafter. However, in the case of unplanned pregnancy, malaria chemoprophylaxis with mefloquine is not considered an indication for pregnancy termination.
Mefloquine is excreted in human milk in small amounts, the activity of which is unknown. Based on a study in a few subjects, low concentrations (3% to 4%) of mefloquine were excreted in human milk following a dose equivalent to 250 mg of the free base. Because of the potential for serious adverse reactions in nursing infants from mefloquine, a decision should be made whether to discontinue the drug, taking into account the importance of the drug to the mother.
Use of mefloquine to treat acute, uncomplicated P. falciparum malaria in pediatric patients is supported by evidence from adequate and well-controlled studies of mefloquine in adults with additional data from published open-label and comparative trials using mefloquine to treat malaria caused by P. falciparum in patients younger than 16 years of age. The safety and effectiveness of mefloquine for the treatment of malaria in pediatric patients below the age of 6 months have not been established.
In several studies, the administration of mefloquine for the treatment of malaria was associated with early vomiting in pediatric patients. Early vomiting was cited in some reports as a possible cause of treatment failure. If a second dose is not tolerated, the patient should be monitored closely and alternative malaria treatment considered if improvement is not observed within a reasonable period of time (see DOSAGE AND ADMINISTRATION).
Clinical studies of mefloquine did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. Since electrocardiographic abnormalities have been observed in individuals treated with mefloquine (see PRECAUTIONS) and underlying cardiac disease is more prevalent in elderly than in younger patients, the benefits of mefloquine therapy should be weighed against the possibility of adverse cardiac effects in elderly patients.
At the doses used for treatment of acute malaria infections, the symptoms possibly attributable to drug administration cannot be distinguished from those symptoms usually attributable to the disease itself.
Among subjects who received mefloquine for prophylaxis of malaria, the most frequently observed adverse experience was vomiting (3%). Dizziness, syncope, extrasystoles and other complaints affecting less than 1% were also reported.
Among subjects who received mefloquine for treatment, the most frequently observed adverse experiences included: dizziness, myalgia, nausea, fever, headache, vomiting, chills, diarrhea, skin rash, abdominal pain, fatigue, loss of appetite, and tinnitus. Those side effects occurring in less than 1% included bradycardia, hair loss, emotional problems, pruritus, asthenia, transient emotional disturbances and telogen effluvium (loss of resting hair). Seizures have also been reported.
Two serious adverse reactions were cardiopulmonary arrest in one patient shortly after ingesting a single prophylactic dose of mefloquine while concomitantly using propranolol (see PRECAUTIONS: Drug Interactions), and encephalopathy of unknown etiology during prophylactic mefloquine administration. The relationship of encephalopathy to drug administration could not be clearly established.
Postmarketing surveillance indicates that the same kind of adverse experiences are reported during prophylaxis, as well as acute treatment.
The most frequently reported adverse events are nausea, vomiting, loose stools or diarrhea, abdominal pain, dizziness or vertigo, loss of balance, and neuropsychiatric events such as headache, somnolence, and sleep disorders (insomnia, abnormal dreams). These are usually mild and may decrease despite continued use.
Occasionally, more severe neuropsychiatric disorders have been reported such as: sensory and motor neuropathies (including paresthesia, tremor and ataxia), convulsions, agitation or restlessness, anxiety, depression, mood changes, panic attacks, forgetfulness, confusion, hallucinations, aggression, psychotic or paranoid reactions and encephalopathy. Rare cases of suicidal ideation and suicide have been reported though no relationship to drug administration has been confirmed.
Cardiovascular Disorders: circulatory disturbances (hypotension, hypertension, flushing, syncope), chest pain, tachycardia or palpitation, bradycardia, irregular pulse, extrasystoles, A-V block, and other transient cardiac conduction alterations.
Skin Disorders: rash, exanthema, erythema, urticaria, pruritus, edema, hair loss, erythema multiforme, and Stevens-Johnson syndrome.
Musculoskeletal Disorders: muscle weakness, muscle cramps, myalgia, and arthralgia.
Other symptoms: visual disturbances, vestibular disorders including tinnitus and hearing impairment, dyspnea, asthenia, malaise, fatigue, fever, sweating, chills, dyspepsia and loss of appetite.
The most frequently observed laboratory alterations which could be possibly attributable to drug administration were decreased hematocrit, transient elevation of transaminases, leukopenia and thrombocytopenia. These alterations were observed in patients with acute malaria who received treatment doses of the drug and were attributed to the disease itself.
During prophylactic administration of mefloquine to indigenous populations in malaria-endemic areas, the following occasional alterations in laboratory values were observed: transient elevation of transaminases, leukocytosis or thrombocytopenia.
Because of the long half-life of mefloquine, adverse reactions to mefloquine may occur or persist up to several weeks after the last dose.
In cases of overdosage with mefloquine, the symptoms mentioned under ADVERSE REACTIONS may be more pronounced. The following procedure is recommended in case of overdosage: Induce vomiting or perform gastric lavage, as appropriate. Monitor cardiac function (if possible by ECG) and neuropsychiatric status for at least 24 hours. Provide symptomatic and intensive supportive treatment as required, particularly for cardiovascular disturbances.
(see INDICATIONS AND USAGE)
Treatment of mild to moderate malaria in adults caused by P. vivax or mefloquine-susceptible strains of P. falciparum.
Five tablets (1250 mg) mefloquine hydrochloride to be given as a single oral dose. The drug should not be taken on an empty stomach and should be administered with at least 8 oz (240 mL) of water.
If a full-treatment course with mefloquine does not lead to improvement within 48 to 72 hours, mefloquine should not be used for retreatment. An alternative therapy should be used. Similarly, if previous prophylaxis with mefloquine has failed, Mefloquine Hydrochloride Tablets should not be used for curative treatment.
Note: Patients with acute P. vivax malaria, treated with mefloquine, are at high risk of relapse because mefloquine does not eliminate exoerythrocytic (hepatic phase) parasites. To avoid relapse after initial treatment of the acute infection with mefloquine, patients should subsequently be treated with an 8-aminoquinoline derivative (eg, primaquine).
One 250 mg Mefloquine Hydrochloride Tablet once weekly.
Prophylactic drug administration should begin 1 week before arrival in an endemic area. Subsequent weekly doses should be taken regularly, always on the same day of each week, preferably after the main meal. To reduce the risk of malaria after leaving an endemic area, prophylaxis must be continued for 4 additional weeks to ensure suppressive blood levels of the drug when merozoites emerge from the liver. Tablets should not be taken on an empty stomach and should be administered with at least 8 oz (240 mL) of water.
In certain cases, eg, when a traveler is taking other medication, it may be desirable to start prophylaxis 2 to 3 weeks prior to departure, in order to ensure that the combination of drugs is well tolerated (see PRECAUTIONS: Drug Interactions).
When prophylaxis with mefloquine fails, physicians should carefully evaluate which antimalarial to use for therapy.
Treatment of mild to moderate malaria in pediatric patients caused by mefloquine-susceptible strains of P. falciparum.
Twenty (20) to 25 mg/kg body weight. Splitting the total therapeutic dose into 2 doses taken 6 to 8 hours apart may reduce the occurrence or severity of adverse effects. Experience with mefloquine in infants less than 3 months old or weighing less than 5 kg is limited. The drug shouId not be taken on an empty stomach and should be administered with ample water. The tablets may be crushed and suspended in a small amount of water, milk or other beverage for administration to small children and other persons unable to swallow them whole.
If a full-treatment with mefloquine does not lead to improvement within 48 to 72 hours, mefloquine should not be used for retreatment. An alternative therapy should be used. Similarly, if previous prophylaxis with mefloquine has failed, mefloquine should not be used for curative treatment.
In pediatric patients, the administration of mefloquine for the treatment of malaria has been associated with early vomiting. In some cases, early vomiting has been cited as a possible cause of treatment failure (see PRECAUTIONS). If a significant loss of drug product is observed or suspected because of vomiting, a second full dose of mefloquine should be administered to patients who vomit less than 30 minutes after receiving the drug. If vomiting occurs 30 to 60 minutes after a dose, an additional half-dose should be given. If vomiting recurs, the patient should be monitored closely and alternative malaria treatment considered if improvement is not observed within a reasonable period of time.
The safety and effectiveness of mefloquine to treat malaria in pediatric patients below the age of 6 months have not been established.
The following doses have been extrapolated from the recommended adult dose. Neither the pharmacokinetics, nor the clinical efficacy of these doses have been determined in children owing to the difficulty of acquiring this information in pediatric subjects. The recommended prophylactic dose of mefloquine hydrochloride is approximately 5 mg/kg body weight once weekly. One 250 mg Mefloquine Hydrochloride Tablet should be taken once weekly in pediatric patients weighing over 45 kg. In pediatric patients weighing less than 45 kg, the weekly dose decreases in proportion to body weight:
30 to 45 kg: 3/4 tablet
20 to 30 kg: 1/2 tablet
10 to 20 kg: 1/4 tablet
5 to 10 kg: tablet*
*Approximate tablet fraction based on a dosage of 5 mg/kg body weight. Exact doses for children weighing less than 10 kg may best be prepared and dispensed by pharmacists.
Experience with mefloquine in infants less than 3 months old or weighing less than 5 kg is limited.
Mefloquine Hydrochloride Tablets are supplied as speckled off-white to yellow, round, flat faced, beveled edge tablets with “54 111” debossed on one side and scored on the other. Each tablet contains 250 mg of mefloquine hydrochloride.
0054-0025-11 250 mg speckled off-white to yellow tablet, bottle of 25
0054-0025-17 250 mg speckled off-white to yellow tablet, 1x25 blister pack
Mefloquine Hydrochloride Tablets should be stored at 25ºC (77ºF); excursions permitted to 15º to 30ºC (59º to 86ºF).
Ocular lesions were observed in rats fed mefloquine daily for 2 years. All surviving rats given 30 mg/kg/day had ocular lesions in both eyes characterized by retinal degeneration, opacity of the lens, and retinal edema. Similar but less severe lesions were observed in 80% of female and 22% of male rats fed 12.5 mg/kg/day for 2 years. At doses of 5 mg/kg/day, only corneal lesions were observed. They occurred in 9% of rats studied.
This Medication Guide is intended only for travelers who are taking mefloquine hydrochloride to prevent malaria. The information may not apply to patients who are sick with malaria and who are taking mefloquine hydrochloride to treat malaria.
An information wallet card is provided at the end of this Medication Guide. Cut it out and carry it with you when you are taking mefloquine hydrochloride.
This Medication Guide was revised in August 2003. Please read it before you start taking mefloquine and each time you get a refill. There may be new information. This Medication Guide does not take the place of talking with your prescriber (doctor or other health care provider) about mefloquine and malaria prevention. Only you and your prescriber can decide if mefloquine is right for you. If you cannot take mefloquine, you may be able to take a different medicine to prevent malaria.
Malaria is an infection that can cause death, and is spread to humans through mosquito bites. If you travel to parts of the world where the mosquitoes carry the malaria parasite, you must take a malaria prevention medicine. Mefloquine hydrochloride is one of a small number of medications approved to prevent and to treat malaria. If taken correctly, mefloquine is effective at preventing malaria but, like all medications, it may produce side effects in some patients.
The most frequently reported side effects with mefloquine, such as nausea, difficulty sleeping, and bad dreams are usually mild and do not cause people to stop taking the medicine. However, people taking mefloquine occasionally experience severe anxiety, feelings that people are against them, hallucinations (seeing or hearing things that are not there, for example), depression, unusual behavior, or feeling disoriented. There have been reports that in some patients these side effects continue after mefloquine is stopped. Some patients taking mefloquine think about killing themselves, and there have been rare reports of suicides. We do not know if mefloquine was responsible for these suicides.
Medicines approved in the United States for malaria prevention include mefloquine hydrochloride, doxycycline, atovaquone/proguanil, hydroxychloroquine, and chloroquine. Not all of these drugs work equally as well in all areas of the world where there is malaria. The chloroquines, for example, do not work in areas where the malaria parasite has developed resistance to chloroquine. Mefloquine may be effective against malaria that is resistant to chloroquine or other drugs. All drugs to treat malaria have side effects that are different for each one. For example, some may make your skin more sensitive to sunlight (mefloquine does not do this). However, if you use mefloquine to prevent malaria and you develop a sudden onset of anxiety, depression, restlessness, confusion (possible signs of more serious mental problems), or you develop other serious side effects, contact a doctor or other health care provider. It may be necessary to stop taking mefloquine and use another malaria prevention medicine instead. If you can't get another medicine, leave the malaria area. However, be aware that leaving the malaria area may not protect you from getting malaria. You still need to take a malaria prevention medicine.
Do not take mefloquine to prevent malaria if you
Tell your prescriber about all your medical conditions. Mefloquine may not be right for you if you have certain conditions, especially the ones listed below:
Tell your prescriber about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Some medicines may give you a higher chance of having serious side effects from Mefloquine Hydrochloride Tablets.
Take mefloquine hydrochloride tablets exactly as prescribed. If you are an adult or pediatric patient weighing 45 kg (99 pounds) or less, your prescriber will tell you the correct dose based on your weight.
To prevent malaria
Mefloquine hydrochloride, like all medicines, may cause side effects in some patients. The most frequently reported side effects with mefloquine when used for prevention of malaria include nausea, vomiting, diarrhea, dizziness, difficulty sleeping, and bad dreams. These are usually mild and do not cause people to stop taking the medicine.
Mefloquine hydrochloride may cause serious mental problems in some patients. (See " What is the most important information I should know about Mefloquine Hydrochloride Tablets?").
Mefloquine hydrochloride may affect your liver and your eyes if you take it for a long time. Your prescriber will tell you if you should have your eyes and liver checked while taking mefloquine.
Medicines are sometimes prescribed for conditions not listed in Medication Guides. If you have any concerns about mefloquine, ask your prescriber. This Medication Guide contains certain important information for travelers visiting areas with malaria. Your prescriber or pharmacist can give you information about mefloquine that was written for health care professionals. Do not use mefloquine for a condition for which it was not prescribed. Do not share mefloquine with other people.
This Medication Guide has been approved by the U.S. Food and Drug Administration.
Revised August 2003
© RLI, 2003
You need to take malaria prevention medicine before you travel to a malaria area, while you are in a malaria area, and after you return from a malaria area.
If taken correctly, mefloquine hydrochloride is effective at preventing malaria but, like all medications, it may produce side effects in some patients.
If you use mefloquine hydrochloride to prevent malaria and you develop a sudden onset of anxiety, depression, restlessness, or confusion (possible signs of more serious mental problems) - contact a doctor or other health care provider. It may be necessary to stop taking mefloquine hydrochloride and use another malaria prevention medicine instead.
Other medicines approved in the United States for malaria prevention include: doxycycline, atovaquone/proguanil, hydroxychloroquine, and chloroquine. Not all malaria medicines work equally well in malaria areas. The chloroquines, for example, do not work in many parts of the world. If you can't get another medicine, leave the malaria area. However, be aware that leaving the malaria area may not protect you from getting malaria. You still need to take a malaria prevention medicine.
Please read the Medication Guide for additional information on mefloquine hydrochloride.
Issued: August 2003
|Mefloquine Hydrochloride (Mefloquine Hydrochloride)|
Data are from FDA and U.S. National Library of Medicine.