Falciparum Malaria Treatment Side Effects

Continuing from last week, of the four treatment regimes recommended for uncomplicated (chloroquine-resistant) falciparum malaria, Artemether-lumefantrine (Coartem™), an artemesinin-combination therapy, will frequently be the treatment of choice.

The most common adverse reactions reported in adults are headache, anorexia, dizziness, physical weakness, arthralgia and myalgia, although these are difficult to separate from the symptoms of malaria. The most common adverse reactions reported in children are fever, cough, vomiting, loss of appetite, and headache.

For treatment of complicated malaria, parenteral Quinine is recommended. Adverse reactions may include: hypoglycemia, auditory and visual disturbances, and cardiac dysrhythmias. Quinine cannot be combined with coartemether, chloroquine, or halofantrine, and mefloquine should only be administered 12 hours after the last dose of quinine (risk of seizures, cardiac toxicity).

For chemoprophylaxis of falciparum malaria, there are several alternatives depending on the region of travel, and patient-specific considerations including preference of dosing frequency. It is important to choose a chemoprophylactic regime that will be well tolerated in order to optimize adherence. Choices include Atovaquone/Proguanil (Malarone™), Doxycycline, and Mefloquine (Lariam™). Chloroquine can only be used for chemoprophylaxis in the regions of the world where malaria is still chloroquine-sensitive (Central America west of Panama Canal, Haiti, the Dominican Republic, and most of the Middle East).

Malarone is generally well-tolerated, but adverse reactions can include: cough, diarrhea, dizziness, headache, anorexia, oral sores, nausea, stomach pain, vomiting, and weakness. Adverse reactions associated with Doxycycline include: gastrointestinal disturbances, esophageal ulcerations, and photosensitivity. Doxycycline is contraindicated in pregnant and breastfeeding women and in children under 8 years of age, and should not be given with dairy products.

Adverse reactions associated with Mefloquine include: gastrointestinal disturbances, dizziness, and headache. Rarely, Mefloquine can cause cardiac dysrhythmias, hypo or hypertension, and skin rash. Occasionally at treatment dose levels (less often at prophylaxis levels), Mefloquine can cause severe neuropsychiatric reactions. Patients should be screened for history of mental illness and substance abuse prior to starting Mefloquine. Mefloquine is contraindicated in patients on sodium valproate, phenytoin, carbamazepine (risk of seizures), coarthemeter, chloroquine, or halofantrine (risk of seizures, cardiac toxicity). See also above under quinine.


Sources:

Centers for Disease Control and Prevention. Reasons for Considering or Avoiding Certain Drugs for the Prevention of Malaria. Available from: http://www.cdc.gov/malaria/control_prevention/drug_avoidance.htm.

Medecins Sans Frontieres. (2006). Essential Drugs: Practical Guidelines. 3rd Ed.