What is the most important information I should know about hydroxychloroquine?
Hydroxychloroquine can cause dangerous effects on your heart, especially if you also use certain other medicines. Seek emergency medical attention if you have fast or pounding heartbeats and sudden dizziness (like you might pass out).
Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye that could progress to permanent vision problems.
Stop taking hydroxychloroquine and call your doctor at once if you have blurred vision, trouble focusing, distorted vision, blind spots, trouble reading, changes in your color vision, increased sensitivity to light.
What is hydroxychloroquine?
Hydroxychloroquine is used to treat or prevent malaria, a disease caused by parasites that enter the body through the bite of a mosquito. Hydroxychloroquine is not effective against all strains of malaria, or against malaria in areas where the infection has been resistant to a similar drug called chloroquine.
Hydroxychloroquine is also used to treat symptoms of rheumatoid arthritis and discoid or systemic lupus erythematosus.
Hydroxychloroquine may also be used for purposes not listed in this medication guide.
What should I discuss with my healthcare provider before taking hydroxychloroquine?
You should not use this medicine if you are allergic to hydroxychloroquine or chloroquine.
High doses or long-term use of hydroxychloroquine may cause irreversible damage to your retina (the membrane layer inside your eye that helps produce vision). This could progress to permanent vision problems. The risk of retinal damage is higher in people with pre-existing eye problems, kidney disease, or people who also take tamoxifen.
Tell your doctor if you have ever had:
- vision changes or damage to your retina caused by an anti-malaria medication;
- heart disease, heart rhythm disorder (such as long QT syndrome);
- diabetes;
- a stomach disorder;
- an allergy to quinine;
- liver or kidney disease;
- psoriasis;
- alcoholism;
- porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system); or
- a genetic enzyme deficiency called glucose-6-phosphate dehydrogenase (G6PD) deficiency.
Tell your doctor if you are pregnant or plan to become pregnant. Malaria is more likely to cause serious illness or death in a pregnant woman. Having malaria during pregnancy may also increase the risk of miscarriage, stillbirth, premature delivery, and low birth weight.
If you are pregnant, your name may be listed on a pregnancy registry to track the effects of hydroxychloroquine on the baby.
It is not known whether hydroxychloroquine will harm an unborn baby. If you are pregnant, ask your doctor about the risks of traveling to areas where malaria is common (such as Africa, South America, and Southern Asia).
It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.
Hydroxychloroquine is not approved for treating lupus or rheumatoid arthritis in anyone younger than 18 years old.
How should I take hydroxychloroquine?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.
Take hydroxychloroquine with a meal or a glass of milk unless your doctor tells you otherwise.
Do not crush or break the tablet.
To treat lupus or arthritis, hydroxychloroquine is usually taken daily.
To prevent malaria: Hydroxychloroquine is usually taken once per week on the same day each week. Start taking the medicine 2 weeks before entering an area where malaria is common. Keep taking the medicine during your stay and for at least 4 weeks after you leave the area.
To treat malaria: Hydroxychloroquine is usually given as one high dose followed by smaller doses during the next 2 days in a row.
Use this medicine for the full prescribed length of time, even if your symptoms quickly improve.
Call your doctor as soon as possible if you have been exposed to malaria, or if you have fever or other symptoms of illness during or after a stay in an area where malaria is common.
Use protective clothing, insect repellents, and mosquito netting around your bed to further prevent mosquito bites that could cause malaria.
No medication is 100% effective in treating or preventing all types of malaria. Talk with your doctor if you have fever, vomiting, or diarrhea during your treatment.
While using hydroxychloroquine, you may need frequent medical tests and vision exams.
Store at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Call your doctor for instructions if you miss a dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of hydroxychloroquine can be fatal, and must be treated quickly.
Overdose symptoms may include drowsiness, vision changes, seizure, slow heart rate, weak pulse, pounding heartbeats, sudden dizziness, fainting, shortness of breath, or slow breathing (breathing may stop).
Keep this medicine out of the reach of children. A hydroxychloroquine overdose can be fatal to a child who accidentally swallows this medicine.
What should I avoid while taking hydroxychloroquine?
This medicine may cause blurred vision and may impair your reactions. Avoid driving or hazardous activity until you know how this medicine will affect you.
Avoid taking an antacid or Kaopectate (kaolin-pectin) within 4 hours before or 4 hours after you take hydroxychloroquine.
What are the possible side effects of hydroxychloroquine?
Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Also seek emergency medical attention if you have symptoms of a serious heart problem: fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might pass out).
Call your doctor at once if you have:
- a seizure;
- yellowing of your eyes;
- ringing in your ears, trouble hearing;
- unusual mood changes;
- severe muscle weakness, loss of coordination, underactive reflexes;
- any sudden changes in mood or behavior, or thoughts about suicide;
- low blood cell counts --fever, chills, tiredness, sore throat, mouth sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath;
- low blood sugar --headache, hunger, sweating, irritability, dizziness, fast heart rate, and feeling anxious or shaky; or
- a serious drug reaction that can affect many parts of your body --skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.
Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye. Stop taking hydroxychloroquine and tell your doctor if you have:
- blurred vision, trouble focusing, trouble reading;
- distorted vision, blind spots;
- changes in your color vision;
- hazy or cloudy vision;
- seeing light flashes or streaks, seeing halos around lights; or
- increased sensitivity to light.
Common side effects may include:
- headache, dizziness;
- nausea, vomiting, stomach pain;
- loss of appetite, weight loss;
- feeling nervous or irritable;
- skin rash or itching; or
- hair loss.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect hydroxychloroquine?
Hydroxychloroquine can cause a serious heart problem. Your risk may be higher if you also use certain other medicines for infections, asthma, heart problems, high blood pressure, depression, mental illness, cancer, malaria, or HIV.
Tell your doctor about all your other medicines, especially:
- cimetidine;
- cyclosporine;
- methotrexate;
- rifampicin;
- praziquantel;
- ampicillin;
- digoxin;
- tamoxifen; or
- heart rhythm medicine.
This list is not complete. Other drugs may affect hydroxychloroquine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Where can I get more information?
Your pharmacist can provide more information about hydroxychloroquine.
