Is Plaquenil the magic drug for COVID-19?
Should we treat Coronavirus COVID-19 with Plaquenil? Does this affect patients with asthma?
Plaquenil was mentioned during a breaking news segment on CBS on March 19, 2020 as a potential treatment for COVID-19 infected patients.
Let’s find out why:
Plaquenil also known as hydroxychloroquine, belongs to a group of medicines called quinolines and is used to treat or prevent malaria, a disease caused by parasites that is contracted through the bite of infected mosquitoes. Plaquenil is also used to treat the symptoms of rheumatoid arthritis, discoid or systemic lupus erythematosus (“lupus”) and even Q fever (a bacterial infection). Plaquenil was FDA approved in 1955 (yes 65 years ago!) comes in a 200 mg tablet form and the usual dose for treating rheumatoid arthritis is 400 to 600 mg per day and for treating “lupus” is 200 to 400 mg per day. The dose is typically taken with milk or a meal. In general, Plaquenil is safe and well tolerated.
How could Plaquenil treat patients with COVID-19?
Chloroquine (which is similar to Plaquenil) is known to block virus infection and replication (the rapid propagation of virus in the body) by increasing endosomial pH and by interfering with the glycosylation of the cellular receptor of COVID-19.
- The problem: Currently, there are no specific medication treatments available for COVID-19!
- A potential treatment: Chloroquine (related to hydroxychloroquine) has been recently reviewed as a potential treatment for COVID-19.
A systematic review on the efficacy and safety of chloroquine for the treatment of COVID-19 was published on line in the Journal of Critical Care by Andrea Cortegiani and others on March 10, 2020. The conclusion after reviewing 6 articles (one narrative letter, one in-vitro study, one editorial, expert consensus paper, 2 national guideline documents) and 23 ongoing clinical trials in China concludes that chloroquine seems to be effective in limiting the replication of SARS-CoV-2 (virus causing COVID-19) in vitro (the laboratory). https://www.sciencedirect.com/science/article/pii/S0883944120303907
Advantages: Chloroquine is a widely used, safe and inexpensive in viral infections in pre-clinical studies.
Plaquenil use in patients with asthma:
There is no contraindication to taking Plaquenil in patients with asthma. In fact, it has been studied for treating asthma patients because of its known anti-inflammatory effect and we know asthma is an inflammatory disease of the airways.
Study: Published in the Journal of Allergy and Clinical Immunology in 1998 by my colleagues from Milwaukee, Wisconsin (Dr. Lauren Charous, Dr. Gary Stevens) showed that in a small group of 8 patients with moderate asthma Plaquenil improved lung function (peak flow and FEV1) and decreased need for albuterol by 18% compared to placebo. Interestingly, it lowered the blood IgE (allergic antibody) levels. https://www.ncbi.nlm.nih.gov/pubmed/9723661
In fair balance, Plaquenil has been associated with side effects especially with long term use.
Side effects of Plaquenil:
Common side effects are headache, nausea, abdominal pain, vomiting, and diarrhea. More serious effects are vision changes, muscle weakness and heart effects.
- Eye: Irreversible retinal damage has been observed in some patients especially if daily doses are greater than 6.5 mg/kg of actual body weight, use greater than 5 years, impaired kidney function, concomitant use of tamoxifen and macular eye disease.
- Heart effects, including Cardiomyopathy and QT prolongation: Plaquenil can prolong the QT interval of the heart rhythm and potentially lead to ventricular arrhythmias which can be life-threatening. Plaquenil can lead to cardiomyopathy. If you have an abnormal heart rhythm or heart problems, check with your doctor and be careful not to use with other medications that can prolong the QT interval.
- Worsening of psoriasis and porphyria: Plaquenil may worsen an attack of psoriasis or porphyria.
- Myopathy and Neuropathy: muscle weakness and nerve problems have been identified in patients taking Plaquenil for long periods of time.
- Neuropsychiatric events, including suicidality: Suicidal behavior has been rarely reported in patients treated with Plaquenil.
- Hypoglycemia: Low blood sugar has been associated with Plaquenil in patients with and without diabetes.
Drug Interactions with Plaquenil:
- Digoxin: This medication is used for heart problems. Plaquenil when taken with digoxin may result in increased digoxin levels, so digoxin levels should be monitored in patients receiving both medications.
- Insulin or antidiabetic drugs: Since Plaquenil may decrease blood sugar, a decrease in insulin or anti-diabetic drugs may be necessary.
- Drugs that prolong QT interval: Plaquenil prolongs the QT interval and should not be administered with other drugs that have may induce cardiac arrhythmias or prolong the QT interval.
- Antiepileptics (seizure medications): Anti-seizure medications might be impaired if taken with Plaquenil.
- Cyclosporin: An increased cyclosporin level was reported when cyclosporin and Plaquenil were taken together.
Stay tuned for potential treatment recommendations; this may include Plaquenil.
At Family Allergy & Asthma Care of Montana, we want to keep you up to date on the most recent issues in COVID-19 treatment.
This information is solely for informational purposes and not intended as a substitute for consultation with a medical professional.