Aralen (Chloroquine Phosphate)

(klor' oh kwin)

Chloroquine is currently being studied for the treatment and prevention of coronavirus disease 2019 (COVID-19). Several chloroquine clinical studies are ongoing in people with COVID-19 in China and other countries, but more information is needed to know how well it works to treat or prevent COVID-19. While there are reports that chloroquine can keep the virus from spreading in your body and shorten the time that you feel sick, there also are concerns about side effects and drug interactions that may occur from taking it. Of note, the FDA has approved an Emergency Use Authorization (EUA) to allow chloroquine to treat adults and adolescents who weigh at least 110 pounds (50 kg) and who are hospitalized with COVID-19, but who are unable to participate in a clinical study. Chloroquine should ONLY be taken under the direction of a doctor.

Chloroquine phosphate is used to prevent and treat malaria. It is also used to treat amebiasis. Chloroquine phosphate is in a class of drugs called antimalarials and amebicides. It works by killing the organisms that cause malaria and amebiasis.

Chloroquine phosphate comes as a tablet to take by mouth. For prevention of malaria in adults, one dose is usually taken once a week on exactly the same day of the week. Your doctor will tell you how many tablets to take for each dose. One dose is taken beginning 2 weeks before traveling to an area where malaria is common, while you are in the area, and then for 8 weeks after you return from the area. If you are unable to start taking chloroquine for 2 weeks before traveling, your doctor may tell you to take double the dose right away (for the first dose). For treatment of sudden, severe attacks of malaria in adults, one dose is usually taken right away, followed by half the dose 6 to 8 hours later and then half the dose once a day for the next 2 days. For prevention and treatment of malaria in infants and children, the amount of chloroquine phosphate is based on the child's weight. Your doctor will calculate this amount and tell you how much chloroquine phosphate your child should receive. For treatment of amebiasis, one dose is usually taken for 2 days and then half the dose every day for 2 to 3 weeks. It is usually taken in combination with other amebicides. Chloroquine phosphate may cause an upset stomach. Take chloroquine phosphate with food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use chloroquine phosphate exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.

Before using chloroquine phosphate,
• tell your doctor and pharmacist if you are allergic to chloroquine phosphate, chloroquine hydrochloride, hydroxychloroquine (Plaquenil), or any other drugs.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention acetaminophen (Tylenol, others); azithromycin (Zithromax); cimetidine (Tagamet); cyclosporine (Gengraf, Neoral, Sandimmune); insulin and oral medications for diabetes; medications for seizures such as carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Teril), phenytoin (Dilantin, Phenytek), or valproic acid (Depakene); certain medications for irregular heartbeat such as amiodarone (Pacerone); methotrexate (Trexall, Xatmep); moxifloxacin (Avelox); praziquantel (Biltricide); and tamoxifen (Nolvadex). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with chloroquine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
• if you are taking antacids, take them 4 hours before or 4 hours after chloroquine. If you are taking ampicillin, take it at least 2 hours before or 2 hours after chloroquine.
• tell your doctor if you have or have ever had liver disease, heart disease, a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death), an irregular heartbeat, a low level of magnesium or potassium in your blood, G-6-PD deficiency (an inherited blood disease), hearing problems, porphyria or other blood disorders, psoriasis, seizures, vision problems, diabetes, weakness in your knees and ankles, or if you drink large amounts of alcohol.
• tell your doctor if you have ever had vision changes while taking chloroquine phosphate, chloroquine hydrochloride, or hydroxychloroquine (Plaquenil).
• tell your doctor if you are pregnant or plan to become pregnant. If you become pregnant while using chloroquine phosphate, call your doctor.
• tell your doctor if you are breastfeeding or plan to breastfeed. Chloroquine phosphate can harm a nursing infant.
• do not have any vaccinations without talking to your doctor.

Unless your doctor instructs you otherwise, continue your normal diet while taking chloroquine phosphate.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Side effects from chloroquine phosphate can occur. Tell your doctor if any of these symptoms are severe or do not go away:

• headache
• nausea
• loss of appetite
• diarrhea
• upset stomach
• stomach pain
• rash
• itching
• hair loss

If you experience any of the following symptoms, call your doctor immediately:

• seeing light flashes and streaks
• blurred vision
• reading or seeing difficulties (words disappear, seeing half an object, misty or foggy vision)
• difficulty hearing
• ringing in ears
• muscle weakness
• drowsiness
• vomiting
• irregular heartbeats
• convulsions
• difficulty breathing
• mood or mental changes
• decreased consciousness or loss of counsciousness
• thinking about harming or killing yourself

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light and excess heat and moisture (not in the bathroom). Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program. It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Children are especially sensitive to an overdose, so keep the medication out of the reach of children. Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests and electrocardiograms (EKG, a test to monitor your heart rate and rhythm) to check your response to chloroquine phosphate. Your doctor will also test your reflexes to see if you have muscle weakness that may be caused by the drug. If you are taking chloroquine phosphate for a long period of time, your doctor will recommend frequent eye exams. It is very important that you keep these appointments. Chloroquine phosphate can cause serious vision problems. If you experience any changes in vision, stop taking chloroquine phosphate and call your doctor immediately. Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription. It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies. ¶ This branded product is no longer on the market. Generic alternatives may be available.