Primaquine is used with other medications to prevent and treat malaria caused by mosquito bites in countries where malaria is common. Malaria parasites can enter the body through these mosquito bites, and then live in body tissues such as red blood cells or the liver. Primaquine is used after other medications (such as chloroquine) have killed the malaria parasites living inside red blood cells. Primaquine then kills the malaria parasites living in other body tissues. This prevents the return of the infection. Both drugs are needed for a complete cure. Primaquine phosphate belongs to a class of drugs known as antimalarials.
The United States Centers for Disease Control provide updated guidelines and travel recommendations for the prevention and treatment of malaria in different parts of the world. Discuss the most recent information with your doctor before traveling to areas where malaria occurs.
OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.
This drug may also be used with other medications to treat pneumocystis pneumonia (PCP) in AIDS patients.
Take this medication by mouth, usually once daily with food to prevent stomach upset, or as directed by your doctor. Follow your doctor's directions exactly. Primaquine is usually taken for 2 weeks after you have left the malarious area. It is started during the last 1-2 weeks of your other malaria treatment or immediately after you have finished your other treatment. Primaquine should not be taken for more than 14 days for malaria treatment.
Dosage is based on the kind of infection you have and your response to treatment. Take this medication regularly. To help you remember, take it at the same time every day.
It is very important to continue taking this medication exactly as prescribed by your doctor. Do not take more or less of this drug than prescribed. Do not stop taking it before completing treatment, even if you feel better, unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause prevention/treatment to be ineffective, cause the amount of parasite to increase, make the infection more difficult to treat (resistant), or worsen side effects.
It is important to prevent mosquito bites (such as by using appropriate insect repellents, wearing clothes that cover most of the body, remaining in air-conditioned or well-screened areas, using mosquito nets, using insect-killing spray). Buy insect repellent before traveling. The most effective insect repellents contain diethyltoluamide (DEET). Ask your doctor or pharmacist to recommend the appropriate strengths of mosquito repellent for you/your children.
No drug treatment is completely effective in preventing malaria. Therefore, seek immediate medical attention if you develop symptoms of malaria (such as fever, chills, headache, other flu-like symptoms), especially while in the malarious area and even after completing this prescription. Quick treatment of malaria infection is needed to prevent serious, possibly fatal, outcomes.
When using primaquine phosphate for treatment of infection, tell your doctor if your condition persists or worsens.
Nausea, vomiting, stomach upset, and abdominal cramps may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if any of these rare but very serious side effects occur: signs of serious infection (such as high fever, severe chills, persistent sore throat), signs of a sudden loss of red blood cells (such as severe tiredness, brown urine, pale lips/nails/skin, fast heartbeat/breathing with usual activities), signs of a certain blood problem (methemoglobinemia, including bluish skin/lips/nails, headache, shortness of breath, lightheadedness, weakness, confusion, chest pain, sudden pounding heartbeat).
Get medical help right away if any of these rare but serious side effects occur: fast/irregular heartbeat, severe dizziness, fainting.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking primaquine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: immune system disease (such as lupus, rheumatoid arthritis), blood problems (such as low white blood cell counts, anemia), history of blood problems due to primaquine (such as hemolytic anemia, methemoglobinemia), personal/family history of favism, low levels of certain blood enzymes (glucose-6-phosphate dehydrogenase-G6PD, NADH methemoglobin reductase).
Your doctor may order a blood test to see if you have any enzyme deficiency before starting primaquine.
Primaquine may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using primaquine, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using primaquine safely.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).
The manufacturer states that during pregnancy, this medication should be used only when clearly needed. While you are pregnant, traveling to an area with malaria places you and your infant at a much higher risk for death and other problems. The CDC recommends continuing your other malaria treatment (such as chloroquine) throughout pregnancy until delivery to prevent harm to your unborn baby (hemolytic anemia). After delivery, you may finish treatment with primaquine. Discuss the risks and benefits with your doctor.
It is not known whether this drug passes into breast milk and the effect on a nursing infant is unknown. The doctor should test your infant for G6PD deficiency before breastfeeding. Consult your doctor before breast-feeding.
The effects of some drugs can change if you take other drugs or herbal products at the same time. This can increase your risk for serious side effects or may cause your medications not to work correctly. These drug interactions are possible, but do not always occur. Your doctor or pharmacist can often prevent or manage interactions by changing how you use your medications or by close monitoring.
To help your doctor and pharmacist give you the best care, be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products) before starting treatment with this product. While using this product, do not start, stop, or change the dosage of any other medicines you are using without your doctor's approval.
Some products that may interact with this drug include: penicillamine, quinacrine, drugs that may cause decreased blood cells (such as trimethoprim, zidovudine, pyrimethamine, azathioprine).
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
If overdose is suspected, contact a poison control center or emergency room right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: extreme drowsiness, seizures, fast/irregular heartbeat.
Do not share this medication with others.
Laboratory and/or medical tests (such as G6PD blood test, blood cell counts) should be performed at the start of treatment and periodically to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
Information last revised April 2015. Copyright(c) 2015 First Databank, Inc.
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