Ivermectin is an old drug.
It is used to treat and prevent some infections caused by parasites and worms.
Long ago, it was first developed to treat parasites, worms and mites in animals.
These include livestock like cattle and horses, and household pets like dogs and cats.
You can see it in the heartworm medicine that you use for dogs.
For humans, it is used to treat:
- Parasitic worms
The diseases of strongyloidiasis, which are intestinal threadworms, and onchocerciasis (river blindness, which is not common in Malaysia, but more usually seen in sub-Saharan Africa and some parts of South America).
- Skin and external parasites
Ivermectin is also formulated as creams that can be used to treat lice on your head and skin diseases on your face such as rosacea.
Not at the moment, no.
It is not approved by any country’s regulatory body to treat any form of cancer, and that includes Malaysia, the United States, Britain and Singapore.
But it is good that people are talking about it and asking questions so that we can have articles like these to tell people the current information we have about ivermectin and cancer, and let them decide what to take away from it.
A research paper by Chinese scientists, published in 2020 in the journal Pharmacological Research, stated that ivermectin had been reported to inhibit the growth of several cancer cells by regulating multiple signaling pathways.
But the exact mechanism is still unclear.
The scientists began to experiment with ivermectin on cancer cells in the lab setting.
It was found that ivermectin promotes cancer cell death in many cancer cell types, including breast cancer, colorectal cancer and some brain cancers.
Mind you, all this is still in the lab setting with petri dishes and animals, and not in humans.
Because of all this interest, the US National Cancer Institute began to study how ivermectin can affect cancer early this year (2026).
These are pre-clinical studies, which means there are no human subjects involved yet.
Therefore, oncologists worldwide need more evidence before they can say ivermectin can be used to treat cancer, and they cannot recommend it as a cancer treatment, even if you keep asking them repeatedly.
However, some oncologists may tell you that as a last-ditch attempt, if you are really desperate and have no other treatment choices remaining, you can use it off-label.
This means that you are taking ivermectin for the cancer at your own risk.
If anything happens to you, no cancer authority will be responsible.
Not necessarily.
Many drugs have promising test results in lab studies, and sometimes, even with animals.
But when it comes to human trials, many of them fail.
It can be said that for every 1,000 cancer drugs tested, usually only one out of this 1,000 makes it to the market for human use.
This means as many as 999 cancer drugs fail before they ever come to common human usage.
You happened to hear about ivermectin because it is already in the market as an anti-parasitic treatment, so people online got excited because they could get it fairly easily.
What’s more, no one knows the exact dosage of ivermectin in human cancer treatment.
It is used at a certain dose to treat parasites, but cancer is a whole different beast.
There was a study published in the journal Anticancer Research in June (2026), on a clinical trial involving 197 cancer patients who were prescribed ivermectin and mebendazole off-label.
It was run by an American telemedicine platform.
After six months, 48.4% of patients reported tumour regression or no evidence of the cancer any more.
Stable disease was reported in 36.1%, while 15.6% reported progression of the cancer.
All these patients were treated concurrently with other approved cancer treatments like chemotherapy, radiation and surgery.
The conclusion of this study says that ivermectin and mebendazole need further randomised controlled trials in humans in the real world (i.e. not under controlled conditions).
We don’t know if the patients who reported tumour regression responded to the ivermectin and mebendazole, or to the other cancer treatments they were receiving.
Other cancer treatments like chemotherapy and radiotherapy also have very high tumour regression rates.
These can be as high as 90%, especially when given in the early stages of the cancer.
Therefore, the trial results are open to much interpretation.
Yes. It is generally safe when taken to treat parasitic infections at the recommended doses, but large doses of ivermectin can cause seizures, and even death.
It can also cause (or worsen) nausea, vomiting and diarrhoea, and worsen the side effects of your chemotherapy.
We also don’t know whether or not it interferes negatively with your other cancer therapies.
I hope that this information will help you understand ivermectin better before you blindly rush to recommend it to your loved ones or friends who have cancer.
Dr YLM graduated as a medical doctor, and has been writing for many years on various subjects such as medicine, health, computers and entertainment. For further information, email starhealth@thestar.com.my. The information provided is for educational and communication purposes only, and it should not be construed as personal medical advice. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
