Antimalarial medications are not available over the counter (OTC) in the United States, so a healthcare provider must write a prescription for it. This can be done virtually or at in-person clinics. A consultation with a healthcare provider helps to assess that the correct medication is prescribed for your specific travel, trip details and personal health history.

Yes, antimalarial medications require a prescription from a healthcare provider. In the United States, there are no over-the-counter (OTC) antimalaria drugs.

Depending on the antimalaria medication, you may need to start taking the medication 1-2 days before travel, or as far as several weeks prior to travel. Your provider will discuss how far in advance you need to start the medication to provide you with malaria prevention prior to your travel.

Atovaquone-proguanil (Malarone)⁷

• Contraindications: hypersensitivity to atovaquone, proguanil, or other ingredients in the formulation; severe renal impairment (CrCl <30mL/min)
• Warnings and Precautions: effect may be lessened if actively having diarrhea/vomiting. Can cause elevated liver enzymes; cases of liver failure have occurred. Speak with your provider if you are pregnant, plan to be pregnant or breastfeeding, to discuss risks versus benefits.
• Side Effects: diarrhea, abdominal pain, nausea and headache

Chloroquine (Aralen)⁸ – brand name discontinued

• Contraindications: presence of retinal or visual filed changes either attributable to 4-aminoquinoline compounds or to any other etiology and known hypersensitivity to 4-aminoquinoline compounds.
• Warnings and Precautions: irreversible retinal damage in some long-term or high dosage 4-aminoquinoline therapy has occurred. Retinopathy has been reported (dose related). Long-term users should be evaluated for muscular weakness. May cause a severe attack of psoriasis if used in patients with psoriasis. Usage of chloroquine during pregnancy should be avoided except in the suppression or treatment of malaria. Speak with your provider if you are breastfeeding due to known risks of chloroquine to nursing infants.
• Side Effects: irreversible retinal damage in long-term or high dose therapy, visual disturbances, auditory changes (nerve type deafness, tinnitus, reduced hearing in those with preexisting auditory damage), skeletal muscle myopathy or neuromyopathy, hepatitis, increased liver enzymes, anorexia, nausea, vomiting, diarrhea, abdominal cramps, reports of skin conditions and sensitivity to sunlight. Nervous system events such as seizures, headache, extrapyramidal disorders and neuropsychiatric changes have been reported. Rarely, hematologic and cardiac system changes. Seek medical help if you experience any of these severe side effects.
• Drug or Food Interactions: antacids and kaolin can reduce the absorption of chloroquine, separate intake by at least 4 hours. Cimetidine can inhibit the metabolism of chloroquine, increasing its plasma level— concomitant use of cimetidine should be avoided.

Doxycycline (Doryx)⁹

• Contraindications: hypersensitivity to any tetracycline
• Warnings and Precautions: the use of doxycycline during the last half of pregnancy, infancy, and up to age 8 years of age may cause permanent discoloration of the teeth. Tooth enamel hypoplasia can also occur, where the outer layer of the tooth is thin or missing during development. Speak with your provider if you are pregnant, trying to get pregnant or breastfeeding, as doxycycline should not be used in pregnancy, and it's best avoided in breastfeeding women if possible. Clostridium difficile (C.diff) associated diarrhea (CDAD) has been reported with doxycycline. Symptoms may range in severity from mild diarrhea to fatal colitis. Seek medical help if you experience signs of C.diff such as watery or bloody diarrhea. Doxycycline can increase sensitivity to sunlight, so it's important to protect your skin when using this medication.
• Side Effects: anorexia, nausea, vomiting, and infrequently diarrhea. Although rare, more severe side effects can occur, such as glossitis (smooth, glossy tongue, pain, tenderness), dysphagia (difficulty swallowing), enterocolitis and inflammatory lesions in the anogenital region. Drink a full glass of water with each dose to reduce the risk of esophageal irritation and ulceration. Seek medical help if you experience any of these severe side effects.
• Drug or Food Interactions: the absorption of doxycycline is reduced when taken with bismuth subsalicylate (Pepto-Bismol, Kaopectate). Doxycycline may reduce the efficacy of oral contraceptive pills.

Mefloquine (Lariam)¹⁰ – brand discontinued

• Contraindications: known hypersensitivity to mefloquine or related compounds or to any of the excipients contained in the formulation. Mefloquine should not be used for malaria prophylaxis in those with active depression, a recent history of depression, generalized anxiety disorder, psychosis, schizophrenia or other major psychiatric disorders, or with a history of convulsions.
• Warnings and Precautions: can cause neuropsychiatric events in adults and children. Neurologic symptoms such as dizziness or - vertigo, tinnitus, and loss of balance have been - reported. May increase the risk of convulsions in - patients with epilepsy. Elimination of mefloquine - may be prolonged in patients with impaired liver - function, leading to higher risk of adverse - events. Transient cardiac events have been seen; - the benefits of mefloloquine therapy should be - weighed against the possibility of adverse effects - in patients with cardiac disease. Cases of - agranulocytosis and aplastic anemia have been - reported. Speak with your provider if you are - breastfeeding to discuss risks.
• Side Effects: vomiting, dizziness, syncope, extrasystoles
• Drug or Food Interactions: ketoconazole and halofantrine should not be taken with mefloquine or within 15 weeks of the last dose of mefloquine due to the risk of a potentially fatal prolongation of the QTc interval.