Uses

What is hydroxychloroquine used for?

Hydroxychloroquine is commonly used for the following conditions.

  • Prevention and treatment of malaria (an infection from parasites that can lead to death, often from a mosquito bite)
  • Treatment of rheumatoid arthritis (a type of arthritis where your immune system damages your joints)
  • Treatment of systemic lupus erythematosus (a condition where your immune system attacks your body tissues)
  • Treatment of discoid lupus erythematosus (a skin condition with a disc-like rash often on the scalp or face, that can lead to scars, changes in skin color, and hair loss)

Hydroxychloroquine may also be used for other conditions as determined by your healthcare provider.

How does hydroxychloroquine work (mechanism of action)?

Hydroxychloroquine works by calming down your immune system and killing the parasite that causes malaria.

How is hydroxychloroquine supplied (dosage forms)?

Hydroxychloroquine is available as Plaquenil, Sovuna, and generic hydroxychloroquine in the following dosage forms that are taken by mouth.

  • 100 mg oral tablets
  • 200 mg oral tablets
  • 300 mg oral tablets
  • 400 mg oral tablets

How should I store hydroxychloroquine?

Hydroxychloroquine should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C), for shorter periods of time, such as when transporting it. Store in a cool, dry place in a tightly closed container. Protect from light.

Side Effects

What are the most common side effects of hydroxychloroquine?

The most common side effects of hydroxychloroquine are listed below. Tell your healthcare provider if you have any of these side effects that bother you.

  • Nausea and vomiting
  • Diarrhea
  • Stomach pain

There may be other side effects of hydroxychloroquine that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of hydroxychloroquine?

While less common, the most serious side effects of hydroxychloroquine are described below, along with what to do if they happen.

Heart Problems. Hydroxychloroquine may cause certain heart problems, such as cardiomyopathypulmonary hypertension, and sick sinus syndrome. These can sometimes lead to death. Call your healthcare provider right away if you have any of the following symptoms.

  • Dizziness or feeling lightheaded
  • Changes in your heart rate or rhythm, such as a fast or skipping heartbeat
  • Fainting

Heart Rhythm Changes. Hydroxychloroquine may cause ventricular arrhythmias or a rare dangerous heart rhythm problem called QT prolongation and torsade de pointes. Some people have a higher risk for this, including people who are older, have other people in their family who have had these conditions, have low potassium or magnesium levels, or who take some medicines for other heart rhythm problems. Tell your healthcare provider right away if you faint or have changes in your heart rate or rhythm, such as a fast or skipping heartbeat.

Eye Problems. Hydroxychloroquine may cause damage to part of your eye, called the retina. This can lead to permanent vision problems. The risk is increased in people taking hydroxychloroquine for a long time or at high doses. Your healthcare provider may recommend an eye examination before or while you take hydroxychloroquine. Stop taking hydroxychloroquine and call your healthcare provider if you have any vision changes or notice any of the following symptoms.

  • Trouble seeing (especially in the dark)
  • Trouble adjusting to changes in brightness (especially going from light to dark)

Severe Skin Reactions. Hydroxychloroquine can cause severe skin reactions called Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) that can lead to death if not treated. If you develop a rash, stop taking hydroxychloroquine and call your healthcare provider right away. Get emergency help right away if you have any of the following symptoms of SJS or TEN.

  • Painful red or purple skin that looks burned and peels off
  • Flat red rash or blisters on your skin, mouth, nose, and genitals
  • Red, painful, watery eyes

Severe Allergic Reactions. Hydroxychloroquine may cause allergic reactions, including a specific type of allergic reaction called DRESS. DRESS stands for Drug Reaction with Eosinophilia and Systemic Symptoms. It is also sometimes called multi-organ hypersensitivity. This is a reaction that can affect multiple parts of the body including your liver, kidneys, and heart. Stop taking the medicine and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Shortness of breath, trouble swallowing, or throat tightness
  • Swelling in your feet, ankles, or legs
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain
  • Dark-colored pee
  • Your skin or the whites of your eyes turning yellowish in color (also called jaundice)

Liver Damage. Liver damage, also called hepatotoxicity, can happen when taking hydroxychloroquine. Call your healthcare provider right away if you have any of the following symptoms of liver damage.

  • Nausea or vomiting
  • Stomach or belly pain
  • Fever
  • Weakness or unusual tiredness
  • Itching
  • Loss of appetite
  • Light-colored poop
  • Dark-colored urine
  • Your skin or the whites of your eyes turning yellowish in color (also called jaundice)

Kidney Damage. Kidney damage can happen when taking hydroxychloroquine. Stop taking hydroxychloroquine and call your healthcare provider right away if you have any of the following symptoms of kidney damage.

  • Reduced need to pee
  • Swelling in your feet, ankles, or legs
  • Weakness or unusual tiredness
  • Difficulty catching your breath or chest pain/pressure
  • Confusion
  • Nausea
  • Seizures

Blood Disorders. Hydroxychloroquine can cause blood disorders, such as agranulocytosisaplastic anemia, hemolytic anemia, low platelet levels (thrombocytopenia), and low white blood cell levels (leukopenia). Stop taking hydroxychloroquine and get help right away if you have any of the following symptoms of blood disorders.

  • Fever
  • Shortness of breath
  • Pale or yellowish skin
  • Easy bruising or bleeding
  • Frequent infection
  • Unusual weakness or tiredness
  • Dizziness, lightheadedness, or feeling like you are about to pass out
  • Headache
  • Fast or abnormal heartbeat

Muscle or Nerve Problems. Hydroxychloroquine can cause muscle problems, including muscle pain, weakness, and tenderness called myopathy, or nerve problems called neuropathy. Neuropathy is commonly described as pain, burning, tingling, or numbness. Your healthcare provider may do tests to check for these while you are taking hydroxychloroquine. Stop taking hydroxychloroquine and tell your healthcare provider if you have unexplained muscle weakness.

Suicidal Thoughts and Actions. Hydroxychloroquine may cause suicidal thoughts or actions in a small number of people. This most often happens within the first month of taking the medicine. If you are about to harm yourself, call 911 or call or text 988, the Suicide & Crisis Lifeline. Call your healthcare provider right away if you have any of the following symptoms.

  • New or increased thoughts of suicide or death
  • Suicide attempt
  • New or increased feelings of anxiety, depression, or other unusual changes in mood or behavior

Low Blood Sugar (Hypoglycemia). Hydroxychloroquine can cause low blood sugar, which can be serious and may lead to death. You may need to check your blood sugar more often if you have changes to your diet, exercise regimen, or medicines for diabetes. Do not take hydroxychloroquine and call your healthcare provider right away if you have any of the following symptoms of hypoglycemia.

  • Headache
  • Crankiness or anxiety 
  • Hunger
  • Dizziness or confusion
  • Blurry vision
  • Slurred speech
  • Sweating
  • Feeling jittery or shakiness
  • Fast heartbeat
  • Seizures

Warnings & Precautions

Who should not use hydroxychloroquine?

Allergies to Ingredients. People who are allergic to any of the following should not take hydroxychloroquine.

  • Plaquenil
  • Sovuna
  • Hydroxychloroquine
  • Any other medicine known as a 4-aminoquinoline
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific hydroxychloroquine products they stock.

What should I know about hydroxychloroquine before using it?

Do not take hydroxychloroquine unless it has been prescribed to you by a healthcare provider. Take it as prescribed.

Do not share hydroxychloroquine with other people, even if they have the same condition as you. It may harm them.

Keep hydroxychloroquine out of the reach of children.

You should take hydroxychloroquine with food or milk. 

Do not crush, break, or divide hydroxychloroquine tablets.

People who are 65 or older can be at greater risk for some side effects from hydroxychloroquine. Talk to your healthcare provider about your risks if you are in this age group.

What should I tell my healthcare provider before using hydroxychloroquine?

Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if hydroxychloroquine is right for you.

In particular, make sure that you discuss any of the following.

Connective Tissue Disorders. If you have a connective tissue disorder, you may develop kidney damage while taking hydroxychloroquine.

Porphyria. If you have porphyria, taking hydroxychloroquine might cause liver damage, worsen your porphyria symptoms, or increase the chances of having a severe flare-up.

Psoriasis. If you have psoriasis, taking hydroxychloroquine might worsen your symptoms or increase the chances of having a severe flare-up.

Current and Past Health Conditions. Tell your healthcare provider if you have any of the following.

  • Heart problems
  • Kidney problems
  • Liver problems
  • Diabetes
  • Eye disease or vision problems
  • G6PD deficiency

Other Medicines and Supplements. Hydroxychloroquine may interact with other medicines and supplements. Before taking hydroxychloroquine, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how hydroxychloroquine could affect pregnancy or harm an unborn baby. Tell your healthcare provider if you are or plan to become pregnant. Your healthcare provider will advise you if you should take hydroxychloroquine while you are pregnant or trying to get pregnant. If you become pregnant while taking hydroxychloroquine, you can register for the Pregnancy Registry by calling 877-311-8972. This registry collects safety information about the use of hydroxychloroquine during pregnancy.

Breastfeeding. Hydroxychloroquine passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should take hydroxychloroquine while breastfeeding.

Interactions

Does hydroxychloroquine interact with foods or drinks?

There are no known interactions between hydroxychloroquine and foods or drinks.

It is unknown if drinking alcohol will affect hydroxychloroquine. The risk of liver damage may be higher if you drink alcohol while taking hydroxychloroquine. Heavy drinking can slow your immune response and make it harder for your body to fight infection. 

Does hydroxychloroquine interact with other medicines (drug interactions)?

Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking hydroxychloroquine.

  • Medicines that can cause QT prolongation, which is a potentially dangerous heart rhythm problem
  • A medicine used to control your heart rate or rhythm (antiarrhythmic)
  • A medicine for diabetes
  • Any medicine for seizures, such as carbamazepine, phenytoin, or phenobarbital
  • Mefloquine, which is a medicine to treat malaria 
  • Methotrexate (Trexall and others), which is a medicine commonly used for rheumatoid arthritis or certain types of cancer
  • Cyclosporine (Gengraf, Neoral, Sandimmune, and others), which is a medicine to suppress your immune system
  • Digoxin (Lanoxin), which is a medicine used to treat irregular heartbeat and some types of heart failure
  • Cimetidine (Tagamet HB) or an antacid, which is a medicine used for heartburn
  • Rifampin, which is a medicine commonly used to treat an infection called tuberculosis
  • Praziquantel, which is a medicine used to treat infections from parasites
  • Kaolin, which is a medicine used to for diarrhea
  • Ampicillin, which is an antibiotic used to treat certain bacterial infections 

This may not be a complete list of medicines that can interact with hydroxychloroquine. Always check with your healthcare provider.

Does Hydroxychloroquine interact with other drugs you are taking?
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Overdose/Missed Dose

What should I do if I accidentally use too much hydroxychloroquine?

If you or someone else has taken too much hydroxychloroquine, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of hydroxychloroquine?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.

Drug Survey

Are you currently using Hydroxychloroquine?

This survey is being conducted by the WebMD marketing sciences department.