Read the latest HealthWatch newsletter:  Newsletter 116, Summer 2021

Chloroquine and hydroxychloroquine: Current evidence for their effectiveness in treating COVID-19 - a lay summary

Chloroquine (CQ) and hydroxychloroquine (HCQ) are cheap and widely available drugs that have been used in the treatment of conditions including malaria and rheumatoid arthritis. There has been much media speculation over their potential as treatments for COVID-19. What is the evidence?

  •  Laboratory studies have suggested that CQ and HCQ could have antiviral activity against COVID-19, but evidence in humans is limited to a single trial with a small number of patients. It did not show conclusively that CQ or HCQ are effective against this infection. There is also no long-term data.
  • Further research is also needed to determine the appropriate dosage and how long treatment should last, and to learn more about potential harms from side effects during and after treatment with the drugs. Over twenty human clinical trials have now been registered to test chloroquine and hydroxychloroquine in COVID-19.
  • On the basis of the weak evidence available to date, treatment guidelines have already been written to enable use of CQ and HCQ for certain patients with COVID-19.
  • Of the two drugs, there is evidence that HCQ is the safer.
  • Known side effects of CQ and HCQ include heart rhythm disturbances, upset digestion, and potential harm to kidney and liver, with a higher risk of side effects in those with kidney or liver disease. Contraindications for the use of these drugs must be checked for each individual before treatment.

Mandy Payne, 26 March 2020

This is a lay summary of a report prepared for the Oxford COVID-19 Evidence Service of the Oxford Centre for Evidence Based Medicine, Nuffield Department of Primary Care Health Sciences, University of Oxford by Kerstin Frie and Kome Gbinigie and posted on 26th March 2020.

Disclaimer: the article has not been peer-reviewed; it should not replace individual clinical judgement and the sources cited in the original report should be checked. The views expressed in this commentary represent an interpretation by HealthWatch and do not necessarily represent those of Oxford CEBM, the NHS, the NIHR, or the Department of Health and Social Care. The views are not a substitute for professional medical advice.


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