Fenbendazole is a broad-spectrum benzimidazole anthelmintic with activity against Giardia and other trematodes. It is also used in pet poultry to treat Capillaria infections.
In these experiments, a fenbendazole-containing therapeutic diet was administered to mice with EMT6 tumors. Three daily i.p. injections of fenbendazole did not alter tumor growth or increase the radiation sensitivity of unirradiated or irradiated tumors.
Product Description
This is a pharmaceutical grade fenbendazole powder that is 99%-100% pure. It is the most economical form of fenbendazole available on the market. It comes in a bottle with a plastic scoop and contains 222 mg of fenbendazole per serving. It is fat soluble and can be made water soluble with the addition of DMSO. It is also available in pre measured capsules.
Each supplemented diet was initiated 2 wk prior to subcutaneous flank implantation of 3 107 lymphoma cells and tumor growth was monitored at 4-d intervals until the largest tumor reached a volume of 1500 mm3. Diet supplementation with vitamins alone did not affect tumor growth but when combined with fenbendazole, it significantly inhibited tumor growth, as compared with controls.
The DMSO/fenbendazole treatment combination also decreased cellular proliferation and reduced cell viability in vitro. These effects were associated with a reduction in cytoplasmic free radical production, as shown by the addition of phenol red and tetrazolium bromide staining.
Ingredients
Fenbendazole is a broad-spectrum benzimidazole carbamate anthelmintic. It belongs to a class of drugs called benzimidazole anthelmintics which have been safely used as anthelmintics for over fifty years.
The fenbendazole is formulated into either a powder or pre measured capsules. The fenbendazole powder contains 22% fenbendazole and has 778 mg of excipients per serving. The powder has to be mixed with DMSO for absorption and is fat soluble meaning it must collect in the liver before being changed into a water soluble form that can be absorbed. The capsules are made of fenbendazole and excipients such as poloxymer 188, b-cyclodextrin and anhydrous glucose.
These ingredients make the fenbendazole more water soluble and faster absorbing. Both preparations of fenbendazole contain no fillers or added flavorings. They are the same strength and work equally well. They can be stored at room temperature. In order to kill parasites fenbendazole must be given for 3-5 days, so it should not be administered to chickens that are in the process of growing new feathers (such as young hens or molting cockatiels). Fenbendazole has also been shown to depolymerize microtubules and have antitumor activity.
Dosage
Fenbendazole (methyl N-(6-phenylsulfanyl-1H-benzimidazol-2-yl) carbamate) is a broad-spectrum benzimidazole anthelmintic for use in a variety of animal species. It acts by binding to b-tubulin microtubule subunits and inhibiting polymerization. This drug also has a track record of effectiveness against gastrointestinal trematodes, including Alaria spp., Nanophyetus salmincola, and Heterobilharzia americana.
This medication is safe to use for pregnant dogs and canines who are nursing, but a lower dosage should be administered. The recommended dosage is 11.3 mg per pound of body weight.
When used to treat tumors, this drug has shown no adverse effects on the growth of unirradiated EMT6 carcinoma cells in culture and exhibited strong antitumor activity when given as three daily i.p. injections prior to irradiation. This dose of the drug has also been shown to significantly inhibit tumor growth when given to mice with established tumors. Similarly, the same dose was not toxic to normal mouse tissue when administered i.p.
Side Effects
Fenbendazole binds to b-tubulin in nematode cells and inhibits the polymerization of tubulin into microtubules, which are involved in protein synthesis and cell division (Martin 1997). Inhibition of these processes arrests normal biochemical and metabolic functions, causing cell death.
Cells treated with fenbendazole exhibit a characteristic survival curve, with a steep decrease in viability at low drug concentrations and a plateau on which cell number remains relatively constant as the drug concentration increases to near the limit of solubility. Severe hypoxia significantly increased the toxicity of 2-h treatments with fenbendazole, but cell numbers did not differ between cultures treated in severe hypoxia and those in air.
Three daily i.p. injections of fenbendazole did not alter the growth or radiation response of EMT6 tumors in BALB/cRw mice. Tumor-bearing mice were stratified by tumor volume at the time of treatment and irradiated with 10 Gy of x-rays as shown in the graph. At necropsy, fenbendazole-treated animals had fewer lung metastases than controls.fenben lab fenbendazol