Mefloquine (mefloquine HCl)

In the US, dosage of mefloquine hydrochloride is expressed in terms of the salt. Each 250-mg tablet of mefloquine hydrochloride commercially available in the US is equivalent to 228 mg of mefloquine base. Other formulations (e.g., 275-mg mefloquine hydrochloride tablets containing 250 mg of the base) may be available in other countries.

Dosage of mefloquine hydrochloride in children is based on body weight.

The manufacturer makes no specific recommendations regarding the need for dosage adjustment in individuals with renal impairment. When mefloquine is used for malaria prophylaxis, limited data indicate that dosage adjustment is not necessary in individuals undergoing hemodialysis.

The manufacturer makes no specific recommendations regarding the need for dosage adjustment in individuals with hepatic impairment. Pharmacokinetic data indicate that elimination of mefloquine may be prolonged and plasma concentrations may be increased in patients with impaired hepatic function. (See Other Precautions and Contraindications under Cautions: Precautions and Contraindications.)

Mefloquine hydrochloride is administered orally with ample water (at least 8 oz (240 mL) of water for an adult).

The drug should not be administered on an empty stomach.

If a patient receiving mefloquine for the treatment of malaria vomits within 30 minutes after receiving a dose of the drug, another full dose should be administered as a replacement; if a patient vomits within 30-60 minutes after receiving a dose, 50% of the dose should be administered as a replacement. 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.

For administration in children and others who are unable to swallow tablets, mefloquine hydrochloride tablets may be crushed and mixed with a small amount of liquid (e.g., water, milk, other beverage).

When mefloquine hydrochloride doses less than 125 mg (less than one-half of a 250-mg tablet) are indicated for pediatric patients, gelatin capsules containing the calculated pediatric dosage should be prepared extemporaneously by a pharmacist using a crushed tablet.

A mefloquine hydrochloride medication guide has been developed to help individuals understand the risks of malaria, risks and benefits of taking mefloquine to prevent malaria, and the rare but potentially serious adverse effects associated with use of the drug. As required by law, a copy of the mefloquine medication guide must be supplied to patients each time mefloquine is dispensed for prevention of malaria; an information wallet card also is supplied to the patient when the drug is dispensed.

No dosing information is available for this tab.

No dosing information is available for this tab.

Interactions between mefloquine and many other drugs, including cardiac drugs, have not been systematically evaluated. When mefloquine is used for prevention or chemoprophylaxis of malaria in travelers, possible effects of mefloquine on other drugs these individuals are receiving (especially anticoagulants and antidiabetic agents) should be assessed prior to departure.

There are no contraindication interactions for this drug.

There are no severe interactions for this drug.

There are no moderate interactions for this drug.

There is no enhanced messaging for this drug.

There are no contraindication contraindications for this drug.

There are no severe contraindications for this drug.

There are no moderate contraindications for this drug.

There is no enhanced messaging for this drug.

There are no severe adverse reactions for this drug.

There are no less severe adverse reactions for this drug.

No enhanced messaging available.

No enhanced messaging available.

The manufacturer states that mefloquine should be used during pregnancy only when clearly needed and that women of childbearing potential should be advised to use effective contraceptive measures while receiving mefloquine and for up to 3 months after the last dose of the drug.

The CDC and American Academy of Pediatrics (AAP) state that mefloquine is the drug of choice for prevention of malaria in women who are pregnant, or likely to become pregnant, if exposure to chloroquine-resistant P. falciparum is unavoidable. In addition, the CDC states that mefloquine is a drug of choice for the treatment of uncomplicated malaria caused by chloroquine-resistant P. falciparum or chloroquine-resistant P. vivax in pregnant women. (See Uses: Malaria.)

Published data on use of mefloquine for prevention or treatment of malaria during pregnancy, including data from randomized controlled trials, intervention trials, prospective and retrospective cohort studies, and case series, have not shown an increased risk of teratogenic effects or adverse pregnancy outcomes compared to the background rate in the general population. These data include more than 700 exposures to mefloquine in the first trimester of pregnancy and over 2,000 exposures in the second and third trimesters. However, mefloquine was teratogenic in mice, rats, and rabbits when given in dosages that were similar to those used for the treatment of malaria (based on body surface area comparisons). CNS effects (e.g., exencephaly, hydrocephaly, partially missing medulla oblongata) and craniofacial malformations were observed in all 3 species. Mefloquine also was embryotoxic in mice and rabbits at these dosages.

Adverse fetal or pregnancy outcomes were not indicated in a double-blind study and clinical experience that included women who received mefloquine during the second and third trimesters. In addition, the frequencies of spontaneous abortion and congenital malformations in 1133 women exposed to mefloquine during the first trimester of pregnancy (more than 95% received mefloquine for prophylaxis) were within expected background rates, and the abnormalities did not fit a specific pattern and would be difficult to attribute to a single pathogenic mechanism. Data from a study evaluating the relationship between use of mefloquine for the treatment of malaria during pregnancy and pregnancy outcome indicate that mefloquine exposure during pregnancy was not associated with an increased incidence of abortion, low birthweight, neurologic retardation, or congenital malformations; however, mefloquine exposure was associated with a greater risk of stillbirth than exposure to other antimalarials, including quinine.

Small amounts of mefloquine are distributed into breast milk. In one study in a limited number of women, approximately 3-4% of a single 250-mg mefloquine dose was distributed into breast milk. Following administration of a single 250-mg dose of the drug in one woman, mefloquine concentrations in breast milk at 4 and 56 days were 53 and 32 ng/mL, respectively.

The manufacturer states that mefloquine should be used with caution in nursing women. Because the amount of mefloquine consumed by a nursing infant is likely to be small, some clinicians suggest that the risk to nursing infants of maternal use of prophylactic dosages of mefloquine is low. However, the amount of mefloquine present in breast milk is insufficient to provide adequate protection against malaria in the nursing infant and, if chemoprophylaxis is necessary, such infants should receive recommended dosages of an appropriate antimalarial.

No enhanced messaging available.