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Chloroquine

Chloroquine is a drug used to prevent malaria or treat its symptoms. Malaria is often caused by mosquito bites, and chloroquine is common in countries where infection happens frequently. Malaria parasites enter the body through mosquito bites and live in tissues such as red blood cells and liver skin cells. In some cases, it is necessary to take additional medication alongside chloroquine to kill the parasites of malaria living in other tissues in the body. A combination of chloroquine and primaquine is sometimes required to completely cure malaria and prevent the return of the infection. Chloroquine is part of the anti-malarial class of drugs, and was approved in the most recent update to the US Centers for Disease Control guidelines on travel recommendations for the prevention and treatment of malaria. Chloroquine is also effective at treating infections caused by a different kind of parasite known as amoebae. Chloroquine phosphate or Aralen is a drug designed to protect against and treat malaria. This substance is available either in branded or generic form. In some cases, chloroquine can be used to manage the infections caused by amoebae.

What is chloroquine?

Chloroquine is a drug used to prevent malaria or treat its symptoms. Malaria is often caused by mosquito bites, and chloroquine is common in countries where infection happens frequently. Malaria parasites enter the body through mosquito bites and live in tissues such as red blood cells and liver skin cells. In some cases, it is necessary to take additional medication alongside chloroquine to kill the parasites of malaria living in other tissues in the body. A combination of chloroquine and primaquine is sometimes required to completely cure malaria and prevent the return of the infection.

Chloroquine is part of the anti-malarial class of drugs, and was approved in the most recent update to the US Centers for Disease Control guidelines on travel recommendations for the prevention and treatment of malaria. Chloroquine is also effective at treating infections caused by a different kind of parasite known as amoebae.

When is chloroquine used?

It is essential to protect yourself against mosquito bites and the risk of malaria whenever possible. You can do this by using the appropriate insect repellents in countries where malaria is common and wearing clothes that cover most of the body.

While no drug treatment is completely effective at stopping malaria infections from spreading, chloroquine can sometimes be used to reduce your risk of getting an infection. However, you will need to seek medical attention if you begin to develop symptoms while using this drug. Chloroquine tablets can also be used to treat the symptoms of malaria, although it may require the use of additional drugs to fully clear the body of the infection.

How do you use chloroquine?

Chloroquine is available in tablet and liquid form. Usually, doctors advise taking this medication by mouth, and with food to reduce your risk of stomach upset. Your doctor will provide full directions on how to manage your dose, including how frequently you should take chloroquine tablets, and what amount you should be taking. Your doctor will also dictate the length of treatment based on the details of your medical condition. If you are taking chloroquine tablets to prevent malaria, the recommended strategy is to take the tablet once a week on the same day each week – as advised by your doctor. The medication will be available to take a few weeks before you enter the area at risk of infection. You will also need to take the drug every week while you are in the area, and for a number of weeks after leaving the location.

It is essential to choose the time that you take your chloroquine tablet carefully. You will need to take it at least four hours before or after taking a drug for diarrhoea control or taking antacids, for example, as these drugs can bind with chloroquine and stop your body from absorbing the medications. It is crucial to take chloroquine tablets exactly as your doctor has prescribed you to do so. Do not take less or more of this medicine than your doctor tells you, and do not stop taking it before your treatment is complete. Skipping or changing a dose without approval from your doctor can cause your treatment for malaria or its prevention to be ineffective.

What dosages are available?

The dose of chloroquine that you are given will depend on why you are using it. If you are using chloroquine to prevent malaria, the most common dosage is 300 mg – 500 mg of chloroquine once a week. Take the chloroquine tablets after a meal and start taking them at least one week before entering the malaria-infected area. Make sure you continue to take the chloroquine tablets for four weeks after leaving the malaria area.

Children may be given a lower dosage based on their age and weight. Make sure that you follow the instructions provided by your doctor carefully. Your doctor may also combine your dose of chloroquine with proguanil tablets to completely remove malaria from your body if you are taking the drug for treatment purposes. Together, the two tablets can help to remove the malaria parasite from the various tissues of your body. Remember that the dose you are given will depend on your exposure to the malaria parasite, and also your weight. Your doctor will suggest the treatment that is right for you, and you must follow their instructions exactly.

What are the side effects of chloroquine?

Chloroquine is an effective method of preventing and treating malaria infection. However, like many medications, it is possible to experience side effects when taking chloroquine tablets. It is important to tell your doctor straight away if you notice anything unusual, including:

  • Hair bleaching or hair loss;
  • Mood or mental changes, including confusion or personality changes;
  • Hearing changes, such as hearing loss or ringing in the ears;
  • Darkening of tissue or skin inside the mouth;
  • Worsening of conditions such as psoriasis and dermatitis;
  • Signs of infection such as high fever and severe chills;
  • Symptoms of liver disease such as yellowing skin or eyes, abdominal pain or dark urine;
  • Bruising or bleeding that happens easily,
  • Muscle weakness and uncontrolled movements.

Chloroquine tablets can cause low blood sugar. If you notice symptoms such as sudden sweating, hunger, shaking, blurred vision or tingling feet and hands, make sure you tell your doctor immediately. If you have diabetes, it is essential to check your blood sugars as regularly as possible. Your doctor might adjust your medication for diabetes while you are taking chloroquine.

Serious side effects from chloroquine tablets are rare, but seek emergency help straight away if you notice any significant changes to your condition including irregular heartbeat, seizures or fainting and severe dizziness. There is also the risk of eye/vision problems, which are more common when taking this medication over long periods of times. Watch out for light flashes, difficulty reading and complete blindness.

If your tongue, mouth, throat or any other part of your body begins swelling, or you notice trouble breathing and a strange rash, this is a severe allergic reaction and you should contact an emergency health service immediately. If you notice any other changes to your condition not listed above, seek the help of a health professional straight away.

When should you not use chloroquine?

Chloroquine is not the right treatment for everyone. Before taking this drug, tell your pharmacist or doctor if you are allergic to it, or you have any other allergies. It is also important to inform your doctor of your complete medical history, especially:

  • Any enzyme problems such as G6PD;
  • Vision or eye problems;
  • Hearing problems;
  • Kidney or liver disease;
  • Psoriasis;
  • Blood disorders such as porphyria,
  • A history of seizures.

Chloroquine tablets can make your skin more sensitive to the sun. Make sure you protect yourself by limiting your exposure to the sun and sunlamps. Avoid going outside without protective clothing and sunscreen. Remember that chloroquine can cause conditions that affect the rhythm of your heart. Prolonged heart issues can be fatal, so make sure that you contact your doctor if you notice dizziness, fainting or other heart conditions. Your risk of an irregular heartbeat may be increased if you have medical conditions that change your blood pressure, or you have suffered from diseases such as heart failure in the past.

Low levels of magnesium or potassium in the blood can also increase your risk of heart conditions. This risk may increase further if you use diuretics regularly, or you have problems with diarrhoea or vomiting. Chloroquine tablets can affect your blood sugar. If you have diabetes, you will need to discuss this with your doctor before using your new medication. Your doctor will usually ask you to check your blood sugar regularly and share your results with them. You may also need to adjust your medication, diet and exercise routines. During pregnancy, chloroquine tablets should not be taken unless necessary as they may harm unborn babies. You should also note that chloroquine can pass into breast milk. Currently, the effects of chloroquine on a nursing infant are unknown.

Does chloroquine interact with any other medications?

Chloroquine tablets can interact with a range of other medications, changing how they work or reducing the way that the chloroquine tablets work. It is important to discuss all of the drugs that you might be taking with your doctor before taking chloroquine. Remember to tell your doctor about the medicines that have been prescribed to you, and other medications such as cold and flu tablets, supplements or herbal remedies too.

Some of the products that interact with chloroquine include:

  • Mefloquine;
  • Pincillamine;
  • Sulfadozine;
  • Acetaminophen;
  • Isoniazid;
  • Praziquantel,
  • Amiodarone
  • Dofetilide.

Chloroquine should not be used by people also taking cimetidine – the drug commonly used to treat an abundance of stomach acid. Antacids and drugs that affect the formula of your stomach acids can change the way that chloroquine tablets are absorbed. Make sure you talk to your doctor about any medicines you are taking for stomach acid in advance.

Where can you buy chloroquine?

It is possible to buy chloroquine tablets either online or from an approved pharmacy over the counter. Most of the time, the drug will come with a brand attached to it and may come in a combined packet with proguanil tablets depending on the prescription your doctor suggests. Chloroquine tablets are available in their generic form.

Can you obtain chloroquine without a prescription?

It is possible to buy chloroquine tablets over the counter, so you should not need a prescription to buy it. However, it is often a good idea to speak to your doctor about the dosage you should be taking before you buy chloroquine. You will also need to make sure that the drug will not interact negatively with any other medication that you are taking. If you are planning a trip and are concerned about malaria, book an appointment with your doctor before obtaining chloroquine tablets.

References:

Boots Company PLC, Nottingham, Accessed on 6 May 2019, chloroquine and Proguanil Anti-Malarial tablets. Retrieved from: https://www.medicines.org.uk/emc/product/8281/pil

BNF Nice, Accessed on 6 May 2019, chloroquine. Retrieved from: https://bnf.nice.org.uk/drug/chloroquine.html

Hans D. Northdurft, and Kevin C. Kain, 2017, The Travel and Tropical Medicine Manual (Fifth Edition). Retrieved from: https://www.sciencedirect.com/topics/neuroscience/chloroquine

Nicholas J. White, 2014, Manson’s Tropical Infectious Diseases. Retrieved from: https://www.sciencedirect.com/topics/neuroscience/chloroquine

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