Fenbendazole—Friend or Foe?

Fenbendazole, a close relative of our friends albendazole and mebendazole, has a lot in common with a previously little known pharmaceutical, ivermectin.  Like ivermectin, fenbendazole is a terrific dewormer.  Like ivermectin, it has been found to exert an interesting off-label effect.  However, this effect has nothing to do with covid.  It affects that other Big C word—cancer.[1] [2]

I first purchased fenbendazole a couple of years ago.  I wanted to blog about it then, but there wasn’t much in the way of peer-reviewed articles and studies on it.  The article had to be placed on the back burner.  Just in the past year, several more studies have been conducted and the results published in peer-reviewed journals.

Fenbendazole’s use as a treatment for cancer came about when veterinary researchers accidentally discovered that fenbendazole helped cure cancer in animals.[3]  This antiparasitic antibiotic is available without a prescription when sold as a “fish antibiotic” and costs about $1 – 1.50 per dose.  (It’s also sold as a dog dewormer under the name Panacur C.)  Soon, word of the potential cancer treatment spread, first as an inexpensive way to cure (yes, cure) cancer in pets. 

Then Joe Tippens, who was diagnosed with terminal lung cancer that had metastasized throughout his body and was told he had a few months at most to live, heard of fenbendazole’s use in treating cancer in animals.  He figured he had nothing to lose and used it on himself.[4]  Joe Tippens provides many more details about his experience on his blog Get Busy Living/My Cancer Story Rocks.

Fenbendazole has been evaluated and shown to treat the following cancers in laboratories and clinical trials:

• Breast (MCF7 cell lines)[5]
• Colorectal[6]
• Glioblastoma cells[7] (fenbendazole and mebendazole)[8]
• Hepatic (H4IIE cell lines)[9]
• Kidney[10] [11]
• Leukemia[12] [13]
• Liver (HUH7 cell lines)[14]
• Lung[15] (A549 cell lines)[16]
• Lymphoma[17]
• Melanoma (canine) cell lines[18]
• Ovarian cancer (study evaluated mebendazole, a close relative of fenbendazole)[19]
• Pancreatic 
• Paraganglioma[21]
• Prostate cancer cells[22]

One treatment protocol suggests the following combination[23]:

• Fenbendazole, 222 mg per day for 7 days
• Curcumin, 600 mg per day
• CBD oil, 25 mg per day, taken sublingually
• Vitamin E

Some studies indicate that fenbendazole is much more effective when taken with vitamins A, B, D, E, and K. [24]

While fenbendazole can be purchased in capsules as a “fish antibiotic,” it might be more easily and quickly acquired through a feed or pet store.  Sold as Panacur C, it is a common dewormer for dogs. Note that the protocol listed above didn’t provide the number of days that curcumin, CBD oil, or vitamin E were to be taken.

Clearly, there is still a lot of research to be done.  And in a collapsed society we aren’t going to have technology and laboratories to diagnose cancer.  (But tune in tomorrow.)  With difficult cases physicians are going to be relegated to making a lot of guesses.   

Fenbendazole and its cousin mebendazole have been around a long time and have a good safety record.  And they’re inexpensive and commonly used dewormers we may want to have on hand anyway.  Fenbendazole probably doesn’t top the list on items to acquire before life gets interesting, but for those who have concerns about cancer, it might be something to consider.

Links to related posts:

Ivermectin

Mebendazole

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[1] N Dogra, et al., Fenbendazole acts as a moderate microtubule destabilizing agent and causes cancer cell death by modulating multiple cellular pathways. Sci Rep. 2018 Aug 9; Vol 8 No 1, https://pubmed.ncbi.nlm.nih.gov/30093705/ (accessed 7 April 2022).

[2] DS Son, et al., The Antitumor Potentials of Benzimidazole Anthelmintics as Repurposing Drugs, Immune Netw, 4 August 2020, Vol 20 No 4, https://pubmed.ncbi.nlm.nih.gov/32895616/ (accessed 7 April 2022).

[3] P Gao, et al., Unexpected antitumorigenic effect of fenbendazole when combined with supplementary vitamins, J Am Assoc Lab Anim Sci, November 2008, Vol 47 No 6, https://pubmed.ncbi.nlm.nih.gov/19049251/ (accessed 7 April 2022).

[4] Evan Onstot, Edmond man says cheap drugs for dogs cured his cancer, KOCO News 5, 26 April 2019, https://www.koco.com/article/edmond-man-claims-cheap-drug-for-dogs-cured-his-cancer/27276538 (accessed 8 April 2022).

[5] AA Elmaaty, et al., In Silico and In Vitro Studies for Benzimidazole Anthelmintics Repurposing as VEGFR-2 Antagonists: Novel Mebendazole-Loaded Mixed Micelles with Enhanced Dissolution and Anticancer Activity, ACS Omega, 22 December 2021, Vol 7 No 1, https://pubmed.ncbi.nlm.nih.gov/35036753/ (accessed 8 April 2022).

[6] R Florio, et al., Screening of Benzimidazole-Based Anthelmintics and Their Enantiomers as Repurposed Drug Candidates in Cancer Therapy, Pharmaceuticals (Basel), 17 April 2021, Vol 14 No 4,  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072969/ (accessed 7 April 2022).

[7] LW Ren, et al., Benzimidazoles induce concurrent apoptosis and pyroptosis of human glioblastoma cells via arresting cell cycle. Acta Pharmacol Sin. 2022 Jan; Vol 43 No 1,   https://pubmed.ncbi.nlm.nih.gov/34433903/ (accessed 7 April 2022).

[8] RY Bai, et al., Antiparasitic mebendazole shows survival benefit in 2 preclinical models of glioblastoma multiforme, Neuro Oncol., September 2011, Vol 13 No 9, https://pubmed.ncbi.nlm.nih.gov/21764822/ (accessed 7 April 2022).

 

[9] D. Park, Fenbendazole Suppresses Growth and Induces Apoptosis of Actively Growing H4IIE Hepatocellular Carcinoma Cells via p21-Mediated Cell-Cycle Arrest, Biol Pharm Bull. 2022, Vol 45 No 2, https://pubmed.ncbi.nlm.nih.gov/35110505/ (accessed 8 April 2022).

[10] What Is Fenbendazole and How Can It Affect Cancer Treatment? Fenbendazole.org, 19 December 2019, https://www.fenbendazole.org/2019/12/19/what-is-fenbendazole-and-how-can-it-affect-cancer-treatment/ (accessed 7 April 2022).

[11] RS Chiang, et al., Fenbendazole-enhancing anti-tumor effect: A case series, Clinical Oncology Case Report, Vol 4 No 2, https://www.scitechnol.com/peer-review/fenbendazole-enhancing-antitumor-effect-a-case-series-2Kms.php?article_id=14307 (accessed 7 April 2022).

[12] Y KalantarMotamedi, et al., Transcriptional drug repositioning and cheminformatics approach for differentiation therapy of leukaemia cells, Sci Rep., 15 June 2021, Vol 11 No 1, https://pubmed.ncbi.nlm.nih.gov/34131166/ (accessed 7 April 2022).

[13] JL Wiley, et al., Chronic myelogenous leukemia in a great horned owl (Bubo virginianus), J Avian Med Surg., March 2009, Vol 23 No 1, https://pubmed.ncbi.nlm.nih.gov/19530405/ (accessed 7 April 2022).

[14] AA Elmaaty, et al., In Silico and In Vitro Studies for Benzimidazole Anthelmintics Repurposing as VEGFR-2 Antagonists: Novel Mebendazole-Loaded Mixed Micelles with Enhanced Dissolution and Anticancer Activity, ACS Omega, 22 December 2021, Vol 7 No 1, https://pubmed.ncbi.nlm.nih.gov/35036753/ (accessed 8 April 2022).

[15] N Dogra, et al., Impairment of the ubiquitin-proteasome pathway by methyl N-(6-phenylsulfanyl-1H-benzimidazol-2-yl)carbamate leads to a potent cytotoxic effect in tumor cells: a novel antiproliferative agent with a potential therapeutic implication, J Biol Chem., 31 August 2012 , Vol 287 No 36, https://pubmed.ncbi.nlm.nih.gov/22745125/ (accessed 7 April 2022).

[16] AA Elmaaty, et al., In Silico and In Vitro Studies for Benzimidazole Anthelmintics Repurposing as VEGFR-2 Antagonists: Novel Mebendazole-Loaded Mixed Micelles with Enhanced Dissolution and Anticancer Activity, ACS Omega, 22 December 2021, Vol 7 No 1, https://pubmed.ncbi.nlm.nih.gov/35036753/ (accessed 8 April 2022).

[17] What Is Fenbendazole and How Can It Affect Cancer Treatment? Fenbendazole.org, 19 December 2019, https://www.fenbendazole.org/2019/12/19/what-is-fenbendazole-and-how-can-it-affect-cancer-treatment/ (accessed 7 April 2022).

[18] S Kim, et al., G2/M arrest and mitotic slippage induced by fenbendazole in canine melanoma cells. Vet Med Sci. 2022 Jan 12, https://pubmed.ncbi.nlm.nih.gov/35020278/ (accessed 7 April 2022).

[19] S Elayapillai, et al., Potential and mechanism of mebendazole for treatment and maintenance of ovarian cancer, Gynecol Oncol, January 2021, Vol 160 No 1, https://pubmed.ncbi.nlm.nih.gov/33131904/ (accessed 7 April 2022).

[20] R Florio, et al., Screening of Benzimidazole-Based Anthelmintics and Their Enantiomers as Repurposed Drug Candidates in Cancer Therapy, Pharmaceuticals (Basel), 17 April 2021, Vol 14 No 4,  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072969/ (accessed 7 April 2022).

[21] R Florio, et al., Screening of Benzimidazole-Based Anthelmintics and Their Enantiomers as Repurposed Drug Candidates in Cancer Therapy, Pharmaceuticals (Basel), 17 April 2021, Vol 14 No 4,  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8072969/ (accessed 7 April 2022).

[22] MKM Esfahani, et al., PEGylated Mesoporous Silica Nanoparticles (MCM-41): A Promising Carrier for the Targeted Delivery of Fenbendazole into Prostrate Cancer Cells, Pharmaceutics, 2021 Oct 2, Vol 13 No 10,  https://pubmed.ncbi.nlm.nih.gov/34683898/ (accessed 7 April 2022).

[23] Fenbendazole Cancer Protocol, https://healnavigator.com/treatments/fenbendazole-cancer-protocol/ (accessed 8 April 2022).

[24] What Is Fenbendazole and How Can It Affect Cancer Treatment? Fenbendazole.org, 19 December 2019, https://www.fenbendazole.org/2019/12/19/what-is-fenbendazole-and-how-can-it-affect-cancer-treatment/ (accessed 7 April 2022).