Mebendazole: From Pinworm Cure To Cancer Cure?


This is a remarkable story about a little pill that began use as a worm treatment for children, and became a medicine to treat, and prevent, cancer.

Most of us are familiar with this medication. It is mebendazole (MBZ), but is better known as Vermox, Ovex, Antiox, and Pripsen. It is usually used to treat pinworms, roundworms, whip worms, and hookworms. Children sometimes acquire these parasites (adults can as well), and the whole family is given a prescription for mebendazole. I have written for this medication many times over the past 32 years for the treatment of these parasites.

Mebendazole has been in common use for over forty years as an antiparasitic, and has a good safety profile. It is fairly inexpensive, at about 2-3 dollars a pill.

But here’s the amazing news! This little pill, known for its good safety profile and few side effects, has been used to treat, and prevent, cancer.

The fact is we all get cancer in our lifetime…..probably many times. Of the millions of new cells our bodies make each day, some are “mutant cells” and have the ability to cause cancer. Our immune system quickly identifies and destroys these abnormal cells, as long as our immune system is in optimal shape. Sometimes, a few “mutant cells” get past our natural defense system. This is why I write so much about diet, lifestyle, and natural supplements that boost the immune system, especially when its comes to boosting natural killer (NK) cells.

Mebendazole kills cancer cells, even those that are unresponsive to other chemotherapy, without causing harm to normal cells, and with little or no side effects.

Scientists have long known how MBZ works to kill parasites, and as it turns out, cancer cells have something in common with parasites. MBZ selectively targets the spindles of both, while leaving healthy cells untouched.

What is a cellular spindle? Great question! Spindles are a type of scaffold-ladder system in our cells. They are also called microtubules. This network of rigid microtubules inside a cell give shape and structure to the cell. The spindles also transfer various molecules to different parts of the cell, functioning like an interstate system. However, the most vital function of spindles is cell division.

Here is a short video animation of how spindles work:


Here is a video of the microtubules, showing how they assemble and disassemble. What an amazing, complex design!


Remember, mebendazole is highly selective. It interferes with, and inhibits, the assembly of spindles only in cancer cells and parasites. This prevents the ability of the cells to divide. The cells then die due to old age. This is known as apoptosis.


What Is Cancer?

Back to my “mutant” analogy. While in pre-med at The University of Cincinnati, I was fortunate to have a job at Keebler here in Cincinnati (Fairfax), Ohio. I worked third shift, operating a huge machine called a Sig Packer. Before the cookies came down the conveyer belt to me, they were inspected by numerous individuals “upstream” from me. The inspectors were quite good at recognizing, and grabbing, less-than-perfect cookies and removing them before they reached my trusty Sig Packer and me. This is similar to how our immune system works to remove and destroy abnormal cells. After all, we make millions of new cells daily, and a few are bound to be rejects.

When a cell divides, our perception is that the two resulting cells are exactly identical. This is not always accurate. The process of copying DNA is not perfect. Errors occur, but they are not usually serious. If there are too many errors in its DNA code, the cell will not be able to reproduce and the errors die within that cell.

Human cells have a maximum number of times they can reproduce themselves before accumulated errors prevent reproduction. This is known as the Hayflick limit. Most scientists agree that this number is around 60 times.

The lifespan of a cell is determined by the length of a string of molecules attached to the ends of the DNA coils. These are known as telomeres. Think of them as long shoestrings with pieces that may break off when they get worn out. They get shorter with time. The longer a shoestring is, the longer it can last when a few pieces break off. And so it is with telomeres.

Cancer cells are odd in that they have damaged DNA code. This results in the activation of the telomere, causing it to regrow. The Hayflick limit does not apply to cancer cells, so this mutation makes cancer cells essentially immortal. Cancer is then able to do its damage by outnumbering and outliving normal cells.

Present efforts to fight cancer involve attempting to isolate the cancer cells and selectively removing or poisoning them. As they have invaded normal tissue, this presents a problem. Surgery sometimes stimulates growth even more, resulting in a temporary relapse and regrowth. Conventional chemotherapy and radiation are not selective enough to protect healthy cells, so “collateral damage” is often a major problem.

That’s why mebendazole is different. It does not kill the cancer cells with poison. It keeps them from reproducing.


From Antiparasitic To Cancer Treatment

Several years ago, researchers at Johns Hopkins University were trying to give mice cancer through injections. The goal was to create cancer in mice and then attempt to cure it. In one group of mice, cancer could not be induced. The scientists were mystified. It was later found that this group of mice had been given mebendazole for pinworm.

Three years later, trials were underway for the treatment of brain cancer in humans with mebenazole. So mebendazole’s new use was discovered, as many treatments are, quite by accident. An article in The Baltimore Sun, dated May 5, 2014, recounts this well.

But a growing number of integrative doctors were already aware of this, and had been using the medication “off-label” for several years with very good results!

Mebendazole was first made by Janssen Pharmaceutical in 1968. By 1972 it was in wide use as an antiparasitic under the name Vermox. It was inexpensive then, and still is today…..if you can get it. On October 7, 2011, Teva Pharmaceuticals announced they would cease manufacture of this product. It is no longer available from any manufacturer in the U.S. No reason was given for the discontinuation. Interestingly, Johnson and Johnson still markets it throughout much of the world for the treatment of parasites, where it is widely available and inexpensive.

In the U.S., a compounding pharmacy is probably the best option. The cost averages around 2-3 dollars for a compounded 100 mg. capsule.

No matter where you order it, a prescription from your doctor will be needed. Doctors are able to write prescriptions for off-label use if they are comfortable doing so. An integrative physician may be more likely to be aware of, and embrace, this treatment. Mebendazole may also be used along with traditional chemotherapy, surgery, and radiation under your doctor’s direction.

Here is a clinical trial and ongoing research involving mebendazole from the NCBI you may find interesting.

Now that this little pill is potentially more valuable than ever, a company by the name of Introgen Therapeutics, Inc. acquired worldwide rights to the cancer application of mebenazole, which is in preclinical stages of development as a cancer treatment. Please be sure to read about it here.


A Prevention As Well?

Through its inhibition of microtubules in cancer cells, mebendazole could be considered a prophylactic agent as well. Remember, in the above mentioned study at Johns Hopkins University, cancer could not be induced in mice after they had been given mebenazole. I also believe it could be used periodically to “purge” the body of cancerous and pre-cancerous cells which have yet to gain cell mass through uncontrolled growth.


  1. so to me it sounds like cancer is a big money maker they really don’t want a cure so many people suffer and they don’t care I would take that pill if I could get it so my cancer might not come back THANKS FOR SHARING Lorine

  2. Would like to know dosage and where to buy. I tried to email twice with 2 of my different email addresses but neither were accepted. Thank you.

    • Hello,
      Dose depends on the patient’s history and tumor type. An integrative medicine physician would need to evaluate the patient and write a prescription.
      Many compounding pharmacies in the U.S can provide this medication.
      Dr. Maxwell

    • Hello,
      At the present time, most research is directed toward solid tumor cancers.
      Not too sure about effectiveness with leukemia, but an integrative doctor may be willing to use it along with
      an oncologist’s traditional treatment for leukemia.
      Dr. Maxwell

  3. Hello Amin,
    You may be referring to metronidazole, a generic form of Flagyl. It is available in 500 Mg. but is a completely different product.
    The dose of the product discussed in the article, mebendazole, depends on the patient’s history and tumor type.
    Dr. Maxwell

  4. Just wondering what kind of dose I would need I have metastatic squamous cell carcinoma in lungs and ribs from head and neck primary hpv16+

    • Hello Kevin,
      Thank you for sharing this with me. Both the dose and length of treatment are determined by your personal physician.
      Mebendazole is available in the U.S through compounding pharmacies with a doctor’s prescription.
      Dr. Maxwell

    • Hi Sofie,
      Thank you for contacting me. This depends on the patient’s overall health including such things as other medicines being taken, age, and weight.
      It is wise to see an integrative doctor who will prescribe it for you.
      Dr. Maxwell

    • Hello Shane,
      Thank you so much for sharing your story!
      This has been my experience with patients as well.
      Warmest regards,
      Dr. Maxwell

  5. Hello Dr. MaxWell,
    I have gone through the blog in which you mentioned the effectiveness of Metronidazole Pil in Cancer. Thanks for sharing an information about this Pil.
    I am suffering Brain Tumor (Astrocytroma Grade 2, Size 5.7 X 3.6 X 3.4 cm)) and want to take Metronidazole Pil.
    Could you please suggest me dosage and where to buy this Pil?
    Hardik Patel.

    • Hello,

      I am glad to share this information with you.
      As metronidazole is a prescription here in the U.S., it would need to be prescribed by a physician who would need to see you in
      person and be willing to write for it for “off-label” use. At that point, the prescription could be filled by
      a compounding pharmacy here in the U.S.

      I wish you the best of health!

      Dr. Maxwell

  6. Hello Dr Craig Maxwell

    My dad got the Pancreatic Cancer (4th stage) and started the Paclitaxel (Albumin) 100MG in combination with Gemcitabine 1200mg from Nov 2016 to Jan 2017 (3 weeks as one circle). However, Medical Oncology Doctor said his blood result for Hemoglobin is getting lower & CEA, CA19.9 is not good.

    Therefore, Dr changed to TS-1 Capsule 100mg per day since Mar 2017 and finally Dr declined to offer him TS-1 on 23 May 2017.

    My dad starts to take Metronidazole 125mg x 2 per day from today.

    We are living in Hong Kong and no prescription is required. However Vermox Metronidazole is no longer provided in Hong Kong. We try to buy the Metronidazole which manufactured by other Factory.

    Dr Craig Maxwell, any suggestion and hope Metronidazole can help him as my dad feels despite while Dr says he can’t have any treatment anymore.

    Have a good day.

    Cat Lam

    • Hello Ms. Lam,
      I am sorry to hear about all your father is going through.
      However, I am glad to hear he is starting the metronidazole protocol, as it has helped many with cancer.
      Please keep me posted on your father’s progress.
      Warmest regards,
      Dr. Maxwell


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