Chloroquine, hydroxychloroquine, and azithromycin are currently being evaluated as potential treatments for coronavirus disease 2019 (COVID-19), despite limited evidence to support the drugs’ efficacy. For this reason, a review of safety considerations published in the Canadian Medical Association Journal highlights the potentially harmful effects of these drugs on patients’ health.
 
“Physicians and patients should be aware of several rare but potentially life-threatening adverse effects of chloroquine and hydroxychloroquine,” said David Juurlink, MD, PhD, FRCPC, Division of Clinical Pharmacology and Toxicology, Sunnybrook Health Sciences Centre, and a senior scientist at ICES, in a press release.
 
The review presents a synopsis of the potential harms associated with these drugs, as well as their appropriate management based on the available evidence.
 
Potentially harmful effects of these drugs include:
  • cardiac arrhythmias
  • hypoglycemia
  • neuropsychiatric effects, such as agitation, confusion, hallucinations and paranoia
  • interactions with other drugs
  • metabolic variability (some people metabolize chloroquine and hydroxychloroquine poorly and a small percentage metabolize them rapidly, which affects patients’ response to treatment)
  • overdose (chloroquine and hydroxychloroquine are highly toxic at the levels that would cause an overdose and can result in seizures, coma, and cardiac arrest)
  • drug shortages (patients with autoimmune disorders, such as rheumatoid arthritis, lupus, and other chronic diseases, who take hydroxychloroquine to treat these conditions could have problems accessing this drug if it is overprescribed)
 
With this summary of potentially adverse effects of prescribing these drugs, the review emphasizes that the prescription of these medications to patients with COVID-19 should be approached with caution.
 
“Despite optimism (in some, even enthusiasm) for the potential of chloroquine or hydroxychloroquine in the treatment of COVID-19, little consideration has been given to the possibility that the drugs might negatively influence the course of disease,” Juurlink said in a press release. “This is why we need a better evidence base before routinely using these drugs to treat patients with COVID-19.”
 
 
REFERENCES
  1. Juurlink DN. Safety considerations with chloroquine, hydroxychloroquine and azithromycin in the management of SARS-CoV-2 infection. Canadian Medical Association Journal. 2020. doi: 10.1503/cmaj.200528.
  2. Potential harms of chloroquine, hydroxychloroquine and azithromycin for treating COVID-19 [news release]. ScienceDaily; April 8, 2020. sciencedaily.com/releases/2020/04/200408125521.htm. Accessed April 9, 2020.