Drug Database: Primaquine Phosphate

What is primaquine phosphate?What is primaquine phosphate?

What is primaquine phosphate?

Primaquine phosphate is an antimalarial prescription medicine approved by the U.S. Food and Drug Administration (FDA) for preventing relapses of malaria caused by the parasite Plasmodium vivax (P. vivax).

Malaria can be an opportunistic infection (OI) of HIV. An OI is an infection that occurs more frequently or is more severe in people with weakened immune systems—such as people with HIV—than in people with healthy immune systems. To learn more about OIs, read the HIVinfo What is an Opportunistic Infection? fact sheet.

How is primaquine phosphate used in people with HIV?How is primaquine phosphate used in people with HIV?

How is primaquine phosphate used in people with HIV?

The Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV and/or the Guidelines for the Prevention and Treatment of Opportunistic Infections in Children with and Exposed to HIV include recommendations on the use of primaquine phosphate to treat Pneumocystis pneumonia (PCP) and prevent relapses of malaria caused by the parasites P. vivax or P. ovale in people with HIV.

Additionally, the Adult Guidelines reference the Centers for Disease Control and Prevention (CDC) website on malaria, which includes up-to-date recommendations on the use of primaquine phosphate for the treatment and prevention of malaria caused by certain types of parasites. 

The recommended uses may not always be consistent with FDA-approved uses of primaquine phosphate. See the Adult and Pediatric Opportunistic Infection Guidelines for complete information on recommended uses of primaquine phosphate in adults and children with HIV. Primaquine phosphate may have other recommended uses not listed above.

What should I tell my health care provider before taking primaquine phosphate?What should I tell my health care provider before taking primaquine phosphate?

What should I tell my health care provider before taking primaquine phosphate?

Before taking primaquine phosphate, tell your health care provider:

• If you are allergic to primaquine phosphate or any other medicines.
• About any medical conditions you have or have had, especially:
  • Blood-related disorders, including hemolytic anemia, glucose-6-phosphate dehydrogenase (G-6PD) deficiency, and NADH methemoglobin reductase deficiency
  • Rheumatoid arthritis or lupus or any other conditions that may lead to a low number of granulocytes (a type of white blood cell)
  • Heart problems
  • Low potassium or low magnesium  
• About anything that could affect your ability to take medicines, such as difficulty swallowing or remembering to take pills.
• If you are pregnant or plan to become pregnant. Primaquine phosphate should not be used during pregnancy. Talk to your health care provider about the risks of taking primaquine phosphate during pregnancy.
• If you are breast/chestfeeding or plan to breast/chestfeed. For people with HIV in the United States, the Guideline recommends speaking with your health care provider to discuss options for feeding your baby. People with suppressed viral load have a less than 1% chance of transmitting HIV to their baby via their own milk.
• About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Primaquine phosphate may affect the way other medicines or products work, and other medicines or products may affect how primaquine phosphate works. Ask your health care provider if there are interactions between primaquine phosphate and the other medicines you take.

Ask your health care provider about possible side effects from primaquine phosphate. Your health care provider will tell you what to do if you have side effects.

How should I take primaquine phosphate?How should I take primaquine phosphate?

How should I take primaquine phosphate?

Take primaquine phosphate according to your health care provider’s instructions. Your health care provider will tell you how much primaquine phosphate to take and when to take it. Before you start primaquine phosphate and each time you get a refill, read any printed information that comes with your medicine.

How should primaquine phosphate be stored?How should primaquine phosphate be stored?

How should primaquine phosphate be stored?

• Store primaquine phosphate tablets at 77°F (25°C).
• Keep primaquine phosphate tablets in the container that they came in and keep the container tightly closed. Protect the tablets from light. 
• Do not use primaquine phosphate if the original seal over the container opening is broken or missing.
• Throw away primaquine phosphate that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
• Keep primaquine phosphate and all medicines out of reach of children.

Where can I find more information about primaquine phosphate?Where can I find more information about primaquine phosphate?

Where can I find more information about primaquine phosphate?

• Recommendations on the HIV-related uses of primaquine phosphate, from the Guidelines for the Prevention and Treatment of Opportunistic Infections in Adults and Adolescents with HIV and the Guidelines for the Prevention and Treatment of Opportunistic Infections in Children with and Exposed to HIV.
• Centers for Disease Control and Prevention (CDC) website on malaria.
• This Patient Version drug summary is based on the following FDA label(s): Tablet (film coated).
• The American Hospital Formulary Service (AHFS) Patient Medication Information for primaquine phosphate available from Medline Plus.
• Primaquine phosphate-related research studies, from ClinicalTrials.gov. (The ClinicalTrials.gov search can be modified so that you can get results that better match your interests.)