Hydroxychloroquine

Why this is used

Hydroxychloroquine is in a class of drugs called antimalarials. It is used to prevent and treat acute attacks of malaria. It is also used to treat discoid or systemic lupus erythematosus and rheumatoid arthritis in patients whose symptoms have not improved with other treatments. This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How to take it

Hydroxychloroquine comes as a tablet to take by mouth. For prevention of malaria in adults, two tablets are usually taken once a week on exactly the same day of each week. The first dose is taken 1 to 2 weeks before traveling to an area where malaria is common, and then doses are continued for 8 weeks after exposure. For treatment of acute attacks of malaria in adults, four tablets are usually taken right away, followed by two tablets 6 to 8 hours later and then two tablets on each of the next 2 days. For prevention or treatment of malaria in infants and children, the amount of hydroxychloroquine is based on the child's weight. Your doctor will calculate this amount and tell you how much hydroxychloroquine your child should receive. For lupus erythematosus, one or two tablets are usually taken once or twice daily. For rheumatoid arthritis, one to three tablets are usually taken once a day. Hydroxychloroquine can be taken with a glass of milk or a meal to decrease nausea. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take hydroxychloroquine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. If you are taking hydroxychloroquine for symptoms of rheumatoid arthritis, your symptoms should improve within 6 months. If your rheumatoid arthritis symptoms do not improve, or if they worsen, stop taking the drug and call your doctor. Once you and your doctor are sure the drug works for you, do not stop taking hydroxychloroquine without talking to your doctor. Symptoms of rheumatoid arthritis will return if you stop taking hydroxychloroquine.

Side effects

<p></p> <p></p> <p></p> <p>Hydroxychloroquine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

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headache</li>
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dizziness</li>
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loss of appetite</li>
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nausea</li>
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diarrhea</li>
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stomach pain</li>
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vomiting</li>
<li>
skin rash</li></ul></p> <p></p> <p>If you experience any of the following symptoms, call your doctor immediately:

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reading or seeing difficulties (words, letters, or parts of objects missing)</li>
<li>
sensitivity to light</li>
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blurred distance vision</li>
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seeing light flashes or streaks</li>
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difficulty hearing</li>
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ringing in ears</li>
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muscle weakness</li>
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bleeding or bruising of the skin</li>
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bleaching or loss of hair</li>
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mood or mental changes</li>
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irregular heartbeat</li>
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drowsiness</li>
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convulsions</li></ul>If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at <a href='http://www.fda.gov/Safety/MedWatch'>http://www.fda.gov/Safety/MedWatch</a>] or by phone [1-800-332-1088].</p>

Precautions

Before taking hydroxychloroquine, tell your doctor and pharmacist if you are allergic to hydroxychloroquine, chloroquine (Aralen), primaquine, or any other drugs. tell your doctor and pharmacist what prescription and nonprescription drugs you are taking, especially acetaminophen (Tylenol, others), digoxin (Lanoxin), iron-containing medications (including multivitamins), isoniazid (Nydrazid), methotrexate (Rheumatrex), niacin, rifampin (Rifadin, Rimactane), and vitamins and herbal products. tell your doctor if you have or have ever had liver disease, psoriasis, porphyria or other blood disorders, G-6-PD deficiency, dermatitis (skin inflammations), or if you drink large amounts of alcohol. tell your doctor if you have ever had vision changes while taking hydroxychloroquine, chloroquine (Aralen), or primaquine.

Overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Educational reference only — talk to a pharmacist or prescriber about Hydroxychloroquine.