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Prescription Drugs For Preventing Malaria There are several drugs on the market for use in malaria prevention. The drugs listed below are from the CDC and WHO Web sites. This information is for educational purposes only and is not intended to serve as a guide for prescribing information to patients, rather it should serve as a point of information when advising travelers.
Table 1.
Drugs Used in the Prophylaxis of Malaria Drug Usage Adult Dosage Child Dosage Comments Mefloquine In areas with chloroquine- resistant Plasmodium falciparum 228 mg base (250 mg salt) orally, once/week <15 kg: 4.6 mg/kg base (5 mg/kg
salt) orally, once/week 15-19 kg: 1/4 tab/week 20-30 kg: 1/2 tab/week 31-45 kg: 3/4 tab/week >45 kg: 1 tab/week Contraindicated in persons allergic to mefloquine. Not
recommended for persons with epilepsy and other seizure disorders;
with severe psychiatric disorders; or with cardiac conduction
abnormalities. Doxycycline An alternative to mefloquine 100 mg orally, once/day >8 years of age: 2 mg/kg of body weight orally/day up to adult dose of 100 mg/day Contraindicated in children <8 years of age, pregnant women,
and lactating women. Chloroquine phosphate (Aralen®
In areas with chloroquine-sensitive Plasmodium falciparum A less effective alternative for use in areas with chloroquine-resistant
Plasmodium falciparum, only if mefloquine or doxycycline cannot be used. 300 mg base (500 mg salt)orally, once/week 5 mg/kg base (8.3 mg/kg salt) orally, once/week, up to maximum
adult dose of 300 mg base Hydroxy-chloroquine sulfate (Plaquenil®) An alternative to chloroquine 310 mg base (400 mg salt) orally, once/week 5 mg/kg base (6.5 mg/kg salt) orally, once/week, up to maximum
adult dose of 310 mg base Chloroquine + Proguanil A less effective alternative for use in Africa, only if mefloquine or doxycycline cannot be used. Weekly chloroquine dose (as above) plus daily proguanil
dose 200 mg orally, once/day Weekly chloroquine dose (as above) plus daily proguanil dose <2 years: 50 mg/day 2-6 years: 100 mg/day 7-10 years: 150 mg/day >10 years: 200 mg/day Proguanil is not sold in the United States, but it is available
in Canada, Europe, and many African countries. Primaquine Used to decrease the risk of relapses of P. vivax and P.
ovale 15 mg base (26.3 mg salt) orally, once/day
for 14 days after departure from the malarious area. 0.3 mg/kg base (0.5 mg/kg salt) orally once/day for 14 days after
departure from the malarious area. Indicated for persons who have had
prolonged exposure to P.
vivax and/or P. ovale. Contraindicated in patients with
G6PD deficiency. |
Provide Antimalarial Drug Warnings and Instructions for Use
Advise Patients:
- Overdosage of antimalarials can be fatal. Keep drugs in childproof containers out of the reach of children.
- Take antimalarials exactly on schedule without missing doses.
- Purchase antimalarials in the United States before travel overseas. The quality of antimalarials sold outside of the United States may not be reliable.
Mefloquine (brand name Lariam®)
Directions for use:
- The adult dosage is 250 mg salt (one tablet).
- Take the first dose of mefloquine 1 week before arrival in the malaria-risk area, once a week in the malaria-risk area, and once a week for 4 weeks after leaving the malaria-risk area.
- Mefloquine should be taken on a full stomach, for example, after dinner.
Mefloquine side effects
Most travelers who take mefloquine have few,
if any, side effects. The most commonly reported minor side effects include
nausea, dizziness, difficulty sleeping, and vivid dreams. Mefloquine has
very rarely been reported to cause serious side effects, such as seizures,
hallucinations, and severe anxiety. Minor side effects usually do not
require stopping the drug. Travelers who have serious side effects should
see a health care provider.
Mefloquine is contraindicated in persons with a known allergy to mefloquine.
Mefloquine is NOT recommended for travelers with a history of
- Epilepsy or other seizure disorders;
- Severe psychiatric disorders;
- Cardiac conduction abnormalities.
Chloroquine (brand name Aralen®)
Directions for use:
- The adult dosage is 500 mg (salt) chloroquine phosphate.
- Take the first dose of chloroquine 1 week before arrival in the malaria-risk area, once a week in the malaria-risk area, and once a week for 4 weeks after leaving the malaria-risk area.
- Chloroquine should be taken on a full stomach, for example, after dinner, to minimize nausea.
Chloroquine side effects
Although side effects are rare, nausea
and vomiting, headache, dizziness, blurred vision, and itching have been
reported. Chloroquine may worsen the symptoms of psoriasis.
Hydroxychloroquine sulfate (brand name Plaquenil®)
Directions for use:
- The adult dosage is 400 mg (salt).
- Take the first dose of Hydroxychloroquine sulfate 1 week before arrival in the malaria-risk area, once a week in the malaria-risk area, and once a week for 4 weeks after leaving the malaria-risk area.
- Hydroxychloroquine sulfate should be taken on a full stomach, for example, after dinner, to minimize nausea.
- Hydroxychloroquine sulfate may be better tolerated than chloroquine.
Hydroxychloroquine sulfate side effects
Although side effects are
rare, nausea and vomiting, headache, dizziness, blurred vision, and itching
have been reported. Hydroxychloroquine sulfate may worsen the symptoms of
psoriasis.
Directions for use:
- The adult dosage is 100 mg.
- Take the first dose of doxycycline 1 or 2 days before arrival in the malaria-risk area, once a day in the malaria-risk area, and once a day for 4 weeks after leaving the malaria-risk area.
Doxycycline side effects and contraindications
- Doxycycline may cause photosensitivity. Travelers should be advised to avoid midday sun, use an SPF sunscreen of at least 15, wear long-sleeved shirts, long pants, and a hat.
- Advise patients to take doxycycline on a full stomach to minimize nausea. Do not lie down for 1 hour after taking the drug to prevent reflux.
- Doxycycline can predispose women to vaginal yeast infections. Women should be advised to bring an over-the-counter vaginal yeast infection medication for use if vaginal itching or discharge develops.
- Doxycycline is contraindicated in children under the age of 8; teeth may become permanently stained.
- Doxycycline should NOT be used during pregnancy.
- Chloroquine + proguanil will provide some protection against malaria.
- Travelers should be aware that taking the combination of chloroquine + proguanil is a less effective combination than taking mefloquine or doxycycline and may put them at higher risk for malaria.
- Advise immediately seeing a health care provider if they develop fever or flu-like symptoms.
- Patients should prevent mosquito bites to further reduce their risk of developing malaria.
Describe Self-Treatment Medication
Travelers should be reminded that malaria can be fatal. If a traveler develops a fever or other flu-like symptoms, and professional medical care is not available within 24 hours, a self-treatment dose of Fansidar® is recommended. Advise the traveler to seek professional medical care as soon as possible after self-treatment. Fansidar® should not be used if allergic to sulfa drugs. Travelers should continue taking antimalarials as directed after self-treatment.
|
Presumptive Treatment of Malaria |
|
Drug |
Usage |
Adult dosage |
Child Dosage |
|
Fansidar®(pyrimethamine-sulfadoxine) |
Self-treatment drug to be used if professional medical care is not available within 24 hours. |
3 tablets orally as a single dose (75 mg pyrimethamine + 1500 mg sulfadoxine) Seek medical care immediately after treatment. |
5-10 kg: 1/2 tablet 11-20 kg: 1 tablet 21-30 kg: 1 1/2 tablets 31-45 kg: 2 tablets >45 kg: 3 tablets Seek medical care immediately after treatment. |
Another excellent resource is the malaria-risk area and prophylaxis information that is available from the CDC’s Fax Information Service. Travelers and health care providers can call toll-free 1-888-232-3299. The CDC keepsa directory of all the faxes available on travelers’ health, arranged by regions of the world. When calling, request document number 000005.
