What is Chloroquine and Hydroxychloroquine?
Chloroquine is a medication primarily used to prevent and treat malaria in areas where malaria remains sensitive to its effects. Certain types of malaria, resistant strains, and complicated cases typically require different or additional medication.
Hydroxychloroquine is used to treat systemic lupus erythematosus, rheumatic disorders like rheumatoid arthritis, porphyria cutanea tarda, and Q fever, and certain types of malaria. It is considered the first-line treatment for systemic lupus erythematosus. Certain types of malaria, resistant strains, and complicated cases require different or additional medication.
These two are similar medicines – salts of the compound chloroquine with the latter having an additional hydroxy molecule. As per research conducted by Frank Touret and Xavier Lamballerie that was published in the science journal Elsevier while chloroquine was prescribed for malaria, hydroxychloroquine was prescribed for auto-immune disorders involving the joints such as Rheumatoid Arthritis and Lupus. Both can have serious side effects if used indiscriminately but have shown to be effective in combating some kinds of viruses when administered in therapeutic doses under strict medical direction.
A 1960 invitro research found the two drugs to be effective in lowering viral dose and inhibiting pneumonia as well as shortening the course of recovery. Trials carried out with these two drugs since 1960, found them to be effective in treating malaria as well as some of the illnesses called by other corona viruses. But it was not found effective in reducing the rate of recovery in Influenza or Dengue fever.
Usually drugs undergo several phases of clinical trials from animal testing to invitro examinations (laboratory controlled petri dish and test tube tests) to finally Phase 3 double blind trials where a group of volunteers are divided into two categories – one who receive the drug and one group that receives a placebo. Despite a lack of phase 3 double blind clinical trials that would have established the efficacy of the drug beyond doubt, the entire world is looking at chloroquine and hydroxychloroquine as wonder drugs to treat COVID 19 effectively.
Can these two drugs be used to treat COVID-19?
Jennifer Tran, a PharmD and a managed care pharmacist there reported in a US based medical journal GOOD RX the trials carried out so far with the two drugs, as recently as in March 2020. While the reports look positive there has been no followup with peer reviewed research papers on the same therefore the evidence is largely considered anecdotal.
In one study conducted on March 16, 2020 , researchers from China reported in a letter that over 100 people with COVID-19 have been treated with chloroquine. These patients had less severe disease and a shorter illness duration compared to those who did not receive chloroquine.
In a second study, held in France on March 20, 2020, 26 patients were administered 600 mg of Hydroxycholoquine and it was reported they had a lower viral load in their body but the study compared patients from two different hospitals and there were too many variables that could have influenced the outcome. A small percentage of these people had to stop the treatment because of nausea worsening of their condition and even death and some who did better also received the antibiotic azithromycin.
In another randomised trial conducted on 62 hospitalized patients on March 31, 2020 in Wuhan, China, it was found that cough and fever improved a day earlier for those who got 400 mg of hydroxychloroquine for 5 days compared to those who did not get any. Additionally, pneumonia improved in 25 of 31 patients who received hydroxychloroquine (compared to 17 of 31 in the group who didn’t). Larger clinical studies are still needed to better understand the type of patients who may respond best to this treatment, pointed out Tran. In addition to these there have been some trials on the negative impact of these drugs which have several side effects such as causing irregular heart-beat, irreversible vision damage, causing lower blood sugar and worsening conditions like psoriasis.
In one study conducted on March 16, 2020 , researchers from China reported in a letter that over 100 people with COVID-19 have been treated with chloroquine. These patients had less severe disease and a shorter illness duration compared to those who did not receive chloroquine.
In a second study, held in France on March 20, 2020, 26 patients were administered 600 mg of Hydroxycholoquine and it was reported they had a lower viral load in their body but the study compared patients from two different hospitals and there were too many variables that could have influenced the outcome. A small percentage of these people had to stop the treatment because of nausea worsening of their condition and even death and some who did better also received the antibiotic azithromycin.
In another randomised trial conducted on 62 hospitalized patients on March 31, 2020 in Wuhan, China, it was found that cough and fever improved a day earlier for those who got 400 mg of hydroxychloroquine for 5 days compared to those who did not get any. Additionally, pneumonia improved in 25 of 31 patients who received hydroxychloroquine (compared to 17 of 31 in the group who didn’t). Larger clinical studies are still needed to better understand the type of patients who may respond best to this treatment, pointed out Tran. In addition to these there have been some trials on the negative impact of these drugs which have several side effects such as causing irregular heart-beat, irreversible vision damage, causing lower blood sugar and worsening conditions like psoriasis.
Hydroxychloroquine side effects
Get emergency medical help if you have signs of an allergic reaction to hydroxychloroquine: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Taking hydroxychloroquine long-term or at high doses may cause irreversible damage to the retina of your eye. Stop taking this medicine and call your doctor at once if you have trouble focusing, if you see light streaks or flashes in your vision, or if you notice any swelling or color changes in your eyes.
Call your doctor at once if you have:
- headache with chest pain and severe dizziness, fainting, fast or pounding heartbeats;
- very slow heart rate, weak pulse;
- muscle weakness, numbness or tingling;
- low blood sugar - headache, hunger, sweating, irritability, dizziness, nausea, fast heart rate, and feeling anxious or shaky; or
- low blood cell counts - fever, chills, sore throat, weakness or ill feeling, swollen gums, mouth sores, skin sores, rapid heart rate, pale skin, easy bruising, unusual bleeding, feeling light-headed.
Common hydroxychloroquine side effects may include:
- headache, dizziness, ringing in your ears;
- nausea, vomiting, stomach pain;
- loss of appetite, weight loss;
- mood changes, 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.