In pig folliculitis, acetasitol (20 mg/kg; po; once daily for 4 days) has anti-infectious action [1].

Animal/Disease Models: 2-month-old E. coli-infected piglets [1]
Doses: 20 mg/kg
Route of Administration: Po; one time/day for 4 days
Experimental Results: 65% of piglets demonstrated clinical recovery, and no animal diarrhea was observed at the end of treatment .

Absorption, Distribution and Excretion
Absorption appears to be very low, but allergic reactions have been reported following vaginal administration of Acetarsol. Arsenic in Acetarsol is primarily excreted in the urine. Post-administration urinary arsenic concentrations are almost within toxic limits. Pharmacokinetic characteristics have not been studied. Metabolites/Metabolites Pharmacokinetic characteristics have not been studied. Arsenic is primarily absorbed through inhalation or ingestion, with minimal absorption through skin contact. After absorption, arsenic is distributed throughout the body and, if necessary, reduced to arsenite, which is then methylated by arsenite methyltransferases to monomethylarsine (MMA) and dimethylarsonic acid (DMA). Arsenic and its metabolites are primarily excreted in the urine. Arsenic is known to induce the production of the metal-binding protein metallothionein, which reduces the toxicity of arsenic and other metals by binding to them and rendering them biologically inactive, while also possessing antioxidant properties. (L20)

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Biological half-life
The pharmacokinetic characteristics of this product are not discussed.

Toxicity Summary
Arsenic and its metabolites interfere with ATP production through multiple mechanisms. In the citric acid cycle, arsenic inhibits pyruvate dehydrogenase and uncouples oxidative phosphorylation by competing with phosphate, thereby inhibiting energy-related NAD+ reduction, mitochondrial respiration, and ATP synthesis. Increased hydrogen peroxide production may also lead to reactive oxygen species (ROS) generation and oxidative stress. Arsenic's carcinogenicity is influenced by its binding to tubulin, resulting in aneuploidy, polyploidy, and mitotic arrest. Arsenic binding to other protein targets may also lead to altered DNA repair enzyme activity, altered DNA methylation patterns, and cell proliferation. (T1, A17) Protein Binding This pharmacokinetic property was not investigated in this study.

[1]. Argyriou K, et al. Acetarsol in the management of mesalazine-refractory ulcerative proctitis: a tertiary-level care experience. Eur J Gastroenterol Hepatol. 2019 Feb;31(2):183-186.
[2]. V.S. Pandey, et al. Successful therapy of balantidiosis of pigs with acetarsol and oxytetracycline. Veterinary parasitology. 1977, 3(2):189-193.

Acetarsol belongs to the acetamide and aniline classes of compounds. Acetarsol, with the molecular formula N-acetyl-4-hydroxy-m-arsanoic acid, is a pentavalent arsenic compound with antiseptic and anthelmintic properties. It was first discovered in 1921 by Ernest Forno of the Pasteur Institute. Developed by Neolab, it was approved by Health Canada as an antifungal drug on December 31, 1964. It was withdrawn from the market on August 12, 1997. Acetarsol is a pentavalent arsenic compound with antiseptic and anthelmintic properties. Although its mechanism of action is not fully understood, Acetarsol may bind to thiol-containing proteins in parasites, forming a lethal As-S bond. This may inhibit their function and ultimately kill the parasite. Acetarsol is an arsenic compound used as an anti-infective drug. Arsenic is a chemical element with the symbol As and atomic number 33. It is a toxic metalloid with several allotropes: common ones are yellow (molecular nonmetal) and several are black and gray (metalloid). Three metalloids of arsenic exist in nature with different crystal structures (arsenic pyrite and the rarer arsenopyrite and paraarsenic pyrite), but more commonly it forms compounds with other elements. (T3, T59)

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Drug Indications
Arsethrol has been used to treat a variety of diseases, such as syphilis, amebiasis, yaws, trypanosomiasis, and malaria. Acetamidinol has been widely used to treat vaginitis caused by Trichomonas vaginalis and Candida albicans. Oral acetamidinol can be used to treat intestinal amebiasis, while suppository forms of acetamidinol have been used in research to treat proctitis. Protozoan infections are diseases caused by parasites in the protozoan kingdom (which contains a wide variety of organisms). Mechanism of Action The mechanism of action of Acetarsol is not fully understood, but it is speculated that it binds to sulfhydryl-containing proteins in infectious microorganisms, forming a lethal As-S bond. This bond formation impairs protein function, ultimately leading to microbial death. Pharmacodynamics Some reports indicate that Acetarsol can alleviate infection, but these reports also suggest systemic arsenic absorption, which may be physiologically harmful.

C8H10ASNO5

275.09

274.977

97-44-9

55588-51-7 (unspecified hydrochloride salt);5892-48-8 (mono-hydrochloride salt);64046-96-4 (calcium salt);64046-96-4 (unspecified calcium salt)

1985

White to off-white solid powder

72.17°C

220.5°C

4

5

2

15

289

0

O=C(C)NC1C(O)=CC=C([As](O)(O)=O)C=1

ODFJOVXVLFUVNQ-UHFFFAOYSA-N

InChI=1S/C8H10AsNO5/c1-5(11)10-7-4-6(9(13,14)15)2-3-8(7)12/h2-4,12H,1H3,(H,10,11)(H2,13,14,15)

m-Arsanilic acid, N-acetyl-4-hydroxy-

Amarsan OsarsolAmoebal Vagisept NSC-13160 NSC13160NSC 13160

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~20.83 mg/mL (~75.72 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (7.56 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (7.56 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)