Fenbendazole (often referred to as Fenben or Panacur) – a broad spectrum benzimidazole class anthelmintic drug. The medication has been introduced in 1974 and is currently used all over the world. It is inexpensive to produce and is available over-the-counter in many countries. (Source)
In the past couple of decades, it has been noted that fenbendazole and medications of the same class exhibit a measurable anti-cancer effect. Various research demonstrated that anthelmintic drugs alone could be effective in causing regression of various tumor types, they could also be used in combination with other conventional treatment methods. (Source1, Source2, Source3)
These findings led to speculations that fenbendazole could be repurposed for use as a complementary anti-cancer medicine. Intriguingly, benzimidazole class drugs appear to work in a similar fashion as a wide range of modern chemotherapeutic drugs, such as taxols and vinca alkaloids, without the excessive toxicity. (Source)
The available toxicological information suggests that fenbendazole seems to be well tolerated in humans after oral exposure and has very few side effects. However, observations in humans are limited. (Source)
Under normal conditions, pure fenbendazole appears in powder form, whitish color and has poor solubility in water. When dissolved in acetone, the compound emits colored impurities above itself.
Fenbendazole has limited absorption in the intestinal tract after oral administration. When consumed, not more than 10% of the medication is absorbed.
Bioavailability can be increased by the presence of food in the gut. Food slows down the intestines and increases blood flow to the digestive tract, improving the absorption of the medication.
References
Blakemore, W. F. (1974). Studies on the pharmacokinetics of fenbendazole in sheep and rats. Studies on the pharmacokinetics of fenbendazole in sheep and rats
Mukhopadhyay, T., Sasaki, J., Ramesh, R., & Roth, J. A. (2018). Antitumor effects of fenbendazole: A possible role of microtubule disruption
Johnston, M. D., Read, A. F., & Berriman, M. (2009). Repurposing anthelmintic drugs for cancer treatment: Perspectives from evolutionary biology
Choi, S. H., Martinez, M. N., & Weatherly, L. M. (2017). Fenbendazole acts as a moderate microtubule destabilizing agent and causes cancer cell death by modulating multiple cellular pathways
Hoglund, J., Engstrom, A., & Gustafsson, K. (2014). Effectiveness of fenbendazole in the treatment of experimental parasitic infections in animals: Implications for repurposing in oncology
European Medicines Agency (EMA). (2018). Panacur AquaSol: EPAR assessment report for extension
Hi, can you tell me which is better: MCT oil or CBD oil? Is there a best option, or are both effective in aiding the absorption of fenbendazole?
Hello, Peter.
They are not substitutes, they do different things.
MCT oil: Energy support. Helps calories, weight maintenance, and ketone production. Often useful during treatment or low appetite. Not directly anti-cancer.
CBD oil: Symptom support. May help pain, sleep, anxiety, nausea and appetite. Weak direct anti-tumor evidence in humans.
MCT first for nutrition, CBD for symptoms.
Many people use both for different roles.
Hello, when taking fenbendazole with a fat is there any supplements that can be taken with it at the same time? I hate having to split up my supplements and need to eat fats with it everytime. It would just be easier to do it all at the same time. I’m talking supplements as is Milk thistle, Tumeric, Vit d3+k2. Thank you
Hello Jen,
Thank you for your question.
Fenbendazole is commonly taken with a meal containing some fat to support absorption. The supplements you mentioned such as milk thistle, turmeric, and vitamin D3 with K2 are fat soluble or fat compatible and are generally taken with food as well, so many people choose to take them at the same time for convenience.
The main items people usually separate from fenbendazole are binding agents, because they can reduce absorption. Otherwise, supportive supplements that are normally taken with meals are often kept together in one dosing period as long as they are well tolerated.
I have kidney cancer. I had a cyst on the right kidney and doctors said that more than likely it was cancerous and the only way to know for sure was to do surger. So, in 2024 I had a partial Necrosectomy where the surgeon took 1/3 of my kidney. Afterward he said he got all the growth/cyst and went a little larger around the area to make sure he got everything (but the cyst was cancerous). Six months later I go in for a follow-up CT scan. To everyone’s surprise the growth is back and twice as big as the one before. We did a needle biopsy and results came back that it IS cancer again. Doctor is wanting to remove all of the kidney this time. I do not want to do that. I am considering the ivermectin and fenbendazole treatment first (before resorting to removal of the kidney) I am female, 73 years old and weigh 225. I had several health issues that my doctor wants me to be careful when taking the above items. I also had a massive heart attack one year ago. Doing way better, but I am on massive medications of blood thinners because of it. So, I’m reaching out to you. What is the best regimen for me? I need help weaving my way through this.
Dear Myra,
Thank you for your message and for explaining your situation so clearly.
Given your medical history and current medications, a gradual and structured approach is usually preferred. A commonly used starting point is 222 milligrams of fenbendazole taken on a 4 days on and 3 days off schedule. If this is well tolerated, after 1 week the schedule is often adjusted to 6 days on and 1 day off while keeping the same dose. After another week, the dose may be increased to 444 milligrams on a 6 days on and 1 day off schedule, provided you are feeling stable and tolerating it well.
If the first week goes smoothly, some people then choose to introduce ivermectin cautiously. A commonly referenced amount is 0.2 milligrams per kilogram of body weight, taken on the same schedule as fenbendazole. Introducing only one change at a time is generally preferred so tolerance can be assessed clearly.
Because fenbendazole is processed through the liver, many people also choose to support liver function throughout the protocol. This is usually done with gentle liver support supplements and by avoiding alcohol and other unnecessary liver stressors.
Starting slowly, increasing step by step, and adjusting only if you feel comfortable is often considered the most sensible way to approach this.
Hello! Can you take low dose (222mg) while nursing?
Dear Jane,
Thank you for your question.
At this time, there is no reliable safety data on the use of fenbendazole while breastfeeding. It is not known whether fenbendazole or its metabolites are excreted into breast milk, nor what effects they could have on a nursing infant. Because fenbendazole has not been studied for this purpose in humans, any exposure during nursing would be considered unpredictable.
For this reason, we do not recommend using fenbendazole while breastfeeding, even at lower doses such as 222 mg. The most cautious approach is to avoid fenbendazole until breastfeeding has been fully discontinued.
My dad has stage 4 prostate cancer and is taking ADT therapy called Relugolix. Does Fenbendezole interfere in any negative way with this therapy? We are actively wanting Dad to start taking Fenbendezole. Thank you
Hello Sally,
There is no scientific evidence showing that Fenbendazole interferes in a negative way with Relugolix or other androgen deprivation therapies. These treatments act through different mechanisms. Relugolix reduces testosterone levels by blocking GnRH receptors, while Fenbendazole affects microtubule dynamics and cellular metabolism. Because of this, no pharmacological conflict between them has been reported in scientific literature or observed among users who combine both.
Fenbendazole is generally well tolerated when used responsibly and in typical supplemental amounts. If your father decides to begin taking it while on Relugolix, it is recommended to start gradually, observe his overall well-being, and support liver function, since both substances are metabolized in the liver. Commonly used liver-support supplements include milk thistle (silymarin) and N-acetylcysteine (NAC). Maintaining balanced nutrition, hydration, and continuing all prescribed cancer treatments remain important.
My dog has advanced lymphoma and he is currently on prednisone. I am going to try fenbendazole to see if it helps him as opposed to putting him through chemo. My question is, what interaction is there between prednisone and fenbendazole? I’m wondering whether I should take him off the prednisone before starting him on fenben? Or can they be used simultaneously if I feel it’s needed, at least to start?
Dear Jayme,
Fenbendazole and prednisone act through different mechanisms and no harmful drug-drug interaction has been documented between them. Prednisone is an anti-inflammatory corticosteroid, while fenbendazole is a benzimidazole anthelmintic with potential antitumor activity. Their metabolic pathways do not overlap in a way that is known to cause toxicity. Both are processed in the liver, so concurrent use makes monitoring liver function and overall tolerance important. Because of this, providing liver support through hepatoprotective supplements or dietary measures is advisable. Prednisone may mask signs of tumor activity, which can complicate assessment of fenbendazole’s independent effect, but simultaneous administration is not contraindicated and has been reported without specific safety concerns. In practice, they can be used together, provided the animal is observed closely for response and tolerance.
Dear sir/madam,
My psa had gone up in short time span
So i started using ivm (ivermectin) 1 mg/kg body weight once a day in the morning, two hours before taking food.
I skipped taking bread, and reduced (hidden) sugars.
My question is:
Can i use 300 mg fenbendazole beside ivm
and could I better take it together with ivm of separately in the evening ?
Thank you for your message and for outlining your current regimen.
Yes, fenbendazole can be used alongside ivermectin. We recommend taking fenbendazole with food—ideally a meal containing some fat—as it is a fat-soluble compound and is better absorbed in the presence of dietary fat. Taking it without food or with water alone may significantly reduce its bioavailability.
It is also advisable to separate the timing of both compounds. You may continue using ivermectin in the morning as you currently do, and take fenbendazole in the evening with food. This may improve tolerance and reduce potential interactions or gastrointestinal discomfort.
Additionally, since both fenbendazole and ivermectin are metabolized by the liver, we recommend monitoring liver enzyme levels periodically during use. Supporting liver function with appropriate supplements such as milk thistle (silymarin), N-acetylcysteine (NAC), or alpha-lipoic acid (ALA) may be beneficial during your course.
This is the protocol that I use for my cancer and hopefully it will also helpful for you also.
Broccoli Sprouts: for the anti-cancer effect of sulforaphane found in the sprouts.
We order the organic, “Cool Beans non-GMO seeds, 14 oz., on eBay and grow them in a “Botanical Interests Seed Sprouter.” (Available on
Amazon)
This is a 6-day process that we follow for sprouting the seeds:
Day 0: Soak 1 to 2 tablespoons of seeds in a glass for 8 to 12 hours
Day 1: Spoon soaked seeds onto the tray and rinse with a light spray
twice daily, AM and PM
Day 2: Rinse seeds and drain AM, turn tray 90 degrees clockwise,
rinse seeds and drain PM
Day 3: Repeat
Day 4: Repeat
Day 5: Harvest seeds, no need to rinse, from the tray and place in a
plastic container.
Serving size is about 1 tablespoon.
Serve on salad or sandwich etc or eat it alone.
NOTE: Do not eat any dairy 40 minutes before or 40 minutes after
consuming the broccoli sprouts or with/on heated/hot food.
(Also, ONE Organic Brazil Nut can be an emergency substitute
if broccoli sprouts are unavailable.)
Annatto Powder: for the anti-cancer effect of tocotrienol found in the ground annotto seeds.
We order from Amazon in a 3 lb. bag. The owner of this
company is very pleased to hear how his product is helping cancer patients.
The seeds, for all practical purposes, are organic. The ground seeds are
packaged with seed “debris” so it will need to be sifted to remove this.
Wear a mask, gloves and apron when sifting the chaff. Store in a glass jar.
NOTE: Do not get on clothing as the powder will stain. Another use for
annatto is as a dye for foods and fabrics.
I sprinkle 1/8-1/4 teaspoon on my salad daily.
Phenbendazole, Tumeric/Curcumin, CBD oil: for the anti-cancer effect of phenbendazole
protocol found in these ingredients.
One capsule daily after lunch while diagnosed with active cancer(s): The first month with metastasized cancer, take 2 Phenben 222mg capsules daily for at least 6 days per week. At the end of first month, switch to 1 Capsule daily.
Phenbendazole 222 mg (available on Amazon search for “Fenbendazole for Humans” 90 or 120 capsules) you want to take the Fen or Phenben with a “greasy meal… or a salad dressed with olive oil.
Additional Organic Extra Virgin Olive Oil, we use
Kirkland Signature 100% Spanish EVOO since only olive orchards
in Spain are used in the production
Tumeric/Curcumin 2250mg plus organic ginger and bio-perine
with 500mg Curcuminoids (available on Amazon).
Hemp Flower Extract, organic, full spectrum 1000mg, (CBD Oil)
drop under the tongue, holding for one minute before swallowing,
daily at bedtime: (Available on Amazon)
Peavey Mart or TSC may have Fenben
Praise the LORD!
I think you have observed some very interesting points, thanks for the post.
Average Golden Retriever life spans have been cut in half, mostly due to cancers. Have there been any cancer strains that have not responded to Fenbendazole treatment?
Hello Donald,
Golden Retrievers have indeed experienced a significant decrease in average life span, largely due to an increased incidence of cancers. Although fenbendazole has been explored as a potential treatment for various types of cancer in animals and humans, its effectiveness can vary depending on the specific type of cancer and other factors.
Not all cancers respond equally well to fenbendazole. Certain types may be more resistant due to their biological characteristics or reproductive mechanisms, and cancer cells can also develop resistance to treatment. Overall, the effectiveness of fenbendazole can vary significantly between individual dogs, even with the same type of cancer.
Scientific research is ongoing, with scientists continually investigating which types of cancer may be more susceptible to fenbendazole and how to overcome resistance mechanisms.
In conclusion, while fenbendazole shows promise and has been used as an off-label treatment for various cancers, it is not universally effective against all cancer strains. Its effectiveness depends on the type of cancer, the individual dog’s health, and other biological factors.
I would love to know is this affective on prostate cancer ❓
Hello William,
The use of fenbendazole for treating cancer, including prostate cancer, is an area of growing interest. Numerous reports and testimonials from individuals claim that fenbendazole has helped in treating various types of cancer, including prostate cancer. These accounts have generated interest and hope among some patients and caregivers.
Preclinical studies (laboratory or animal studies) have suggested that fenbendazole may possess anticancer properties. These studies indicate that fenbendazole can inhibit the growth of cancer cells and induce apoptosis (programmed cell death) in certain types of cancer cells.
If you decide to use fenbendazole, it is important to keep a close eye on your health, including regularly checking your liver enzyme levels and overall well-being.
my name is eva roman, i have a 40 year old daughter, who has brain cancer, stage 4, gleobasphoma (may have spelled it wrong).
can this be used on her, at this late stage. tumor is in the back of her head
Hello Eva,
Fenbendazole has shown potential benefits in various cancer treatments, including brain cancers, even at advanced stages.
While it is challenging to predict specific outcomes, fenbendazole can be useful as part of her treatment plan. It generally requires a long-term commitment, often between 1 to 4 months, to see significant results. The effectiveness can depend on several factors, including the exact nature of the tumor, her overall health, how her body responds to the treatment, and adherence to the dosing regimen.
Many individuals have reported positive experiences with fenbendazole, but it is important to monitor progress and adjust as needed. Consistency and patience are key to achieving the best possible outcome.
My husband was diagnosed on Nov 7, 2022 with pancreatic cancer don’t know what stage yet .
He took 2 rounds of chemo so far one he takes for 46 hrs every two weeks 1 he take before the 3 day chemo and about the last 40 min he hurts so bad he can’t stand it. Can you help we are in America USA
Please see the following website for more info on fenben protocols and other more natural treatment options. There are also medical professionals you can work with. https://www.fenbendazole.org/fenbendazole-information/what-is-fenbendazole/