Is ivermectin a cure for COVID-19?
Ivermectin is an established antiparasitic medicine. We examine the research about its use as a treatment for COVID-19.
Please note: Information, evidence and advice relating to COVID-19 is constantly changing. The information in this article was correct at the time of writing.
Update 24 August 2022
The Australian National COVID-19 Clinical Evidence Taskforce has issued a strong recommendation against the use of ivermectin outside of randomised clinical trials.
The Taskforce found the available research evidence suggests that ivermectin does not decrease mortality, the need for supplemental oxygen or the need for hospitalisation for people with COVID-19. It also may increase the chance of side effects.
Ivermectin is currently being investigated in the UK as part of the Platform Randomised Trial of Treatments in the Community for Epidemic and Pandemic Illnesses (PRINCIPLE) study, led by the University of Oxford. PRINCIPLE is investigating treatments that can speed up recovery, reduce the severity of symptoms and prevent the need for hospital admission in people at risk of serious illness from COVID-19. The study has so far recruited more than 11,000 volunteers.
On 10 September 2021 the Therapeutic Goods Administration (TGA) placed new restrictions on the prescribing of oral ivermectin. With the introduction of these restrictions, GPs can only prescribe ivermectin for TGA-approved conditions, scabies and certain parasitic infections. Specialists including infectious disease physicians, dermatologists, gastroenterologists and hepatologists (liver disease specialists) will be permitted to prescribe ivermectin for other unapproved indications if they believe it is appropriate for a particular patient.
Why was the media interested in ivermectin?
Since the pandemic began, researchers have been busy trying to find medicines that can prevent, or treat, a COVID-19 infection.
Some researchers, such as vaccine scientists, are focused on making new medicines. Other researchers are investigating existing medicines, to see if they can be ‘repurposed’ as COVID-19 treatments.1-3 This is a long process. Many medicines tested will not be successful.
In cases where positive-sounding research emerges, it quickly makes media headlines.
This has been the case with ivermectin.
Isn’t ivermectin a lice treatment?
Ivermectin is the active ingredient in medicines that treat human and animal diseases caused by parasites (eg, mites, lice, nematode worms).1,3-5 It has been available for these conditions for many decades.
Ivermectin is not commonly used to treat headlice in Australia, but is available for this use in other countries, including the USA.
What does this have to do with COVID-19?
In April 2020, Australian researchers published results from a laboratory experiment showing ivermectin could stop the SARS-CoV-2 virus from multiplying in animal cells under a microscope.6 This discovery was exciting, however even the researchers themselves have cautioned that this one study is not enough to prove the medicine will work against COVID-19 in humans.7 The experiment was performed on monkey cells in test tubes, and the dose of ivermectin used was a lot higher than has ever been given to a human.6-8
More work needs to be done; first, to see if ivermectin works on the SARs-CoV-2 virus in humans, and second, to see if there is an effective dose that is also safe. This type of research will involve clinical trials to study the medicine in human subjects.
Clinical trial evidence is important because people with COVID-19 may already be very unwell, and should not take a medicine that might make them sicker.
Has it already been used for people with COVID-19?
There are some media reports about health professionals in Australia and overseas having ‘success’ using ivermectin as part of COVID-19 treatment.9,10 There are also preliminary trial results that suggest no benefit from this medicine,11 or possibly a shorter hospital stay.12
At the moment, publicly available details about these cases and trials are limited or have not been peer-reviewed (looked at carefully by experts to make sure the data has been analysed correctly and completely).
So, currently there is no clear information that confirms whether ivermectin works as a COVID-19 treatment. Instead, there are still plenty of questions that need to be answered by well-run and correctly planned clinical trials. These questions include:
- what are meaningful results that show benefit with this medicine?
- what is a safe dose to use?
- should other medicines be given as well?
- are there side effects that are harmful?
- can it be given to all patients with COVID-19?
Human clinical trials that include ivermectin as a treatment for COVID-19 are now underway.
Ivermectin is approved in Australia but not for COVID-19
Before a medicine can be sold in Australia, it must be approved by the Therapeutic Goods Administration (TGA), a division of the Australian Government Department of Health. The TGA looks at clinical evidence to assess:
- how effective the medicine is for specific uses, and
- how safe the medicine is.
This information helps the TGA decide who can use the medicine, what doses can be made available, and also what conditions the medicine is approved to treat (these are called indications).
In Australia, ivermectin is approved as a treatment for scabies, the tropical diseases onchocerciasis and strongyloidiasis, and a skin condition called rosacea.13,14 It is considered a safe treatment when used at the correct doses for these conditions.
Ivermectin is only available on prescription.
Ivermectin is not approved to prevent or treat COVID-19. The safety and effectiveness of this medicine for non-approved conditions is unknown.
Does ivermectin have side effects?
Some side effects that may be associated with ivermectin include:
- painful joints or muscles
- unusual tiredness or weakness
- skin rash or itch
- nausea, vomiting, stomach discomfort
- swelling of the face or the legs
- worsening asthma.13,14
Some of these side effects are likely a reaction to the parasite (worm or mite) dying. The side effects are usually temporary.
What medicines can treat COVID-19?
In Australia, two medicines are recommended for use by some people hospitalised with severe COVID-19. You can learn more about the steroid dexamethasone and the antiviral medicine remdesivir on our website.
You can also read the living guidelines from the National COVID-19 Clinical Evidence Taskforce . These guidelines are helping Australian health professionals provide the best evidence-based care to people with COVID-19.
- Australian Commission on Safety and Quality in Health Care. Potential medicines to treat COVID-19. Sydney: ACSQHC, 2020 (accessed 26 August 2020).
- American Society of Health-System Pharmacists. Assessment of evidence for COVID-19-related treatments: Updated 13 August 2020. United States: ASHP, 2020 (accessed 20 August 2020).
- Riva L, Yuan S, Yin X, et al. Discovery of SARS-CoV-2 antiviral drugs through large-scale compound repurposing. Nature 2020.
- NPS MedicineWise. Ivermectin (Stromectol) for typical and crusted scabies. RADAR. Sydney: NPS MedicineWise, 2014 (accessed 14 August 2020).
- US Food and Drug Administration. FDA Letter to stakeholders: Do not use ivermectin intended for animals as treatment for COVID-19 in humans. USA: FDA, 2020 (accessed 26 August 2020).
- Caly L, Druce JD, Catton MG, et al. The FDA-approved drug ivermectin inhibits the replication of SARS-CoV-2 in vitro. Antiviral Res 2020;178:104787.
- Bray M, Rayner C, Noël F, et al. Ivermectin and COVID-19: A report in Antiviral Research, widespread interest, an FDA warning, two letters to the editor and the authors' responses. Antiviral Res 2020;178:104805.
- Momekov G, Momekova D. Ivermectin as a potential COVID-19 treatment from the pharmacokinetic point of view: antiviral levels are not likely attainable with known dosing regimens. Biotechnology & Biotechnological Equipment 2020;34:469-74.
- TrialSite News. Well-respected Australian researcher: Consider triple therapy (ivermectin, zinc, doxycycline) for COVID-19. Utah, USA: TrialSite News, 2020 (accessed 14 August 2020).
- TrialSite News. Broward County doctor using ivermectin off-label combo on COVID-19 patients—it is working & secures county health protocol approval. Utah, USA: TrialSite News, 2020 (accessed 14 August 2020).
- Chowdhury A, Shahbaz M, Karim M, et al. A randomized trial of ivermectin-doxycycline and hydroxychloroquine-azithromycin therapy on COVID19 patients. Bangladesh, 2020 (accessed 20 August 2020).
- Gorial FI, Mashhadani S, Sayaly HM, et al. Effectiveness of ivermectin as add-on therapy in COVID-19 management (pilot trial). medRxiv 2020:2020.07.07.20145979 (accessed 20 August 2020).
- Merck Sharp & Dohme (Australia) Pty Ltd. Ivermectin (Stromectol) product information. South Granville, NSW: MSD (Australia) Pty Ltd, 2013 (accessed 20 August 2020).
- Galderma Australia Pty Ltd. Ivermectin (Soolantra) cream product information. Belrose, NSW: Galderma Australia Pty Ltd, 2020 (accessed 26 August 2020).