Researchers testing the head lice drug Ivermectin as a possible treatment for COVID-19 have seen promising results in lab studies.

But the research is in its early stages and the drug is yet to be tested on people with COVID-19. There’s so much we don’t know, including the right dose and delivery method for people with coronavirus infection.

So if you’re thinking of buying some just in case, think again.

Read more: Coronavirus: how long does it take to get sick? How infectious is it? Will you always have a fever? COVID-19 basics explained

What is Ivermectin currently used for?

Ivermectin is an antiparasitic agent that was isolated in the 1970s from the fermented broth of a species of bacteria called Streptomyces avermitilis.

The drug has been used since the 1980s to treat and prevent diseases related to parasites in humans, pets and livestock, and works by paralysing invertebrate parasites.

In Australia, Ivermectin is mainly used topically in creams and lotions for head lice.

It’s also used in tablet form to treat roundworm infection and as a second-line treatment for scabies and rosacea, a skin condition that causes redness and visible blood vessels in your face.

The pharmaceutical company that makes Ivermectin, MSD, has also been donating the drug to developing countries to treat the parasitic diseases river blindness and elephantiasis for the past 30 years.

Read more: How 2015 Nobel Prize drug might rid Africa of ancient scourges

What are the side effects and potential harms?

When used at the recommended dose, Ivermectin is generally well tolerated. Some of the common side effects include diarrhoea, nausea, dizziness and drowsiness.

Less common is a lack of energy, abdominal pain, constipation, vomiting, tremors, rashes and itching.

Ivermectin may also interact with some medicines, such as the blood-thinning drug warfarin, or worsen some conditions such as asthma.

Ingesting Ivermectin found in topical products for head lice is dangerous. If this occurs, contact the Poison Information Hotline.

How might Ivermectin treat COVID-19?

Recent laboratory data from scientists at Monash University and the Doherty Institute suggests Ivermectin is able to stop SARS-CoV-2, the virus that causes COVID-19, from replicating.

Ivermectin has also been shown to stop other viruses (such as HIV, dengue, influenza and Zika) replicating, at least in the laboratory.

The researchers found Ivermectin had an effect on SARS-CoV-2 after one exposure to the drug. Viral replication was shut down within 24 to 48 hours.

It’s still not clear exactly how Ivermectin works. But it appears to stop the processes that allow proteins to move within the virus. These proteins would normally dampen the body’s antiviral response, allowing the virus to replicate and enhance the infection.

Where is the research on Ivermectin for coronavirus up to?

This research on Ivermectin has been conducted in cell culture (cells grown in a laboratory) and is very preliminary. It provides some promise, but not evidence of an effective treatment in people (yet).

Rigorous clinical trials in people with or exposed to COVID-19 infection are needed to establish the drug works and is safe to use, and in what doses. The laboratory studies of Ivermectin suggest higher concentrations of the drug may be needed beyond a standard dose to have an antiviral impact. So safety monitoring will be important.

If Ivermectin is found to work on people with COVID-19, it needs to be studied as a potential treatment. So researchers need to know: does it prevent COVID-19 infection, reduce the severity of the associated illness, or improve the time to recovery? These are important questions to be answered before it becomes a treatment for COVID-19.

On a positive note, re-purposing drugs such as Ivermectin as a potential treatment for COVID-19 is ideal because development can move quickly to clinical trial testing because we already know it’s safe to use in humans at currently recommended doses.

Read more: In the fight against coronavirus, antivirals are as important as a vaccine. Here's where the science is up to

Should I buy some just in case?

No. It’s too soon to know if the promising laboratory test results will translate into a safe and effective drug for COVID-19 patients. The researchers were very clear Ivermectin should not be used to treat COVID-19 until further testing is complete.

We certainly shouldn’t be stockpiling the drug to use later, especially since we don’t yet know the best way to take Ivermectin, including the right dose. And it could lead to unintended medicine shortages for people who need the drug to treat serious diseases caused by parasites.

Andrew McLachlan receives research funding from the NHMRC, research scholarship funding from GSK for a PhD student under his supervision and has previously received (and disclosed) in kind research support from Pfizer and GSK for investigator initiated research projects. Andrew serves and is paid as an expert on Australian government committees related to medicines regulation and anti-doping.