Absorption, Distribution and Excretion
The volume of distribution is approximately 1 mL/g, with a systemic clearance of 0.27 mL/min and a renal clearance of 0.19 mL/min. Within the first 6 hours after administration, approximately 64%–72% of (14)C acetamide is excreted in the urine, while only 0.5%–0.8% appears in exhaled air. Therefore, approximately 30% of the administered dose is not recovered, suggesting that metabolized acetamide enters the acetic acid pool. After administration of 100 or 1000 mg/kg body weight of 14C acetamide to rats, less than 0.07% of the urinary radioactive material recovered by high-performance liquid chromatography (HPLC) was co-eluted with N-hydroxyacetamide standards. Furthermore, this hydroxyacetamide was not detected after incubation with rat liver microsomes and NADPH, or in primary cultures of rat hepatocytes. 14C-acetamide does not covalently bind to proteins in rat liver microsomes and in the presence of NADPH or cytoplasmic components, while hepatocyte cultures contain unextractable radioactive substances. Cycloheximide inhibits this binding to the same extent as 14C-acetate incorporation into cellular proteins. Metabolism/Metabolites Acetamide…is present in small amounts in human urine and is a metabolite of metronidazole. The metabolism of metronidazole to acetamide is apparently mediated by the gut microbiota. Acetamide is carcinogenic in rats and mice. To elucidate the carcinogenic mechanism of acetamide, we investigated DNA damage caused by the acetamide metabolite acetylhydroxamic acid (AHA) using a DNA fragment labeled at the 32P-5' end. AHA treated with amidase induced DNA damage in the presence of Cu(II) and exhibited a DNA cleavage pattern similar to hydroxylamine. Both catalase and bartophenone inhibited DNA damage, indicating the involvement of H₂O₂ and Cu(I). Carboxyl-PTIO, a specific nitric oxide (NO) scavenger, partially inhibited DNA damage. The amount of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) produced by amidase-treated AHA was similar to that produced by hydroxylamine. Electron spin resonance (ESR) spectroscopy analysis showed that both amidase-treated AHA and hydroxylamine generated NO in the presence of Cu(II). Based on these results, we hypothesize that AHA may be converted to hydroxylamine by amidase. These results suggest that metal-mediated DNA damage mediated by amidase-catalyzed hydroxylamine production plays an important role in the carcinogenicity of acetamide.

---

Biological Half-Life
After intravenous injection of (14)C acetamide into rats, the average half-life of radioactivity in the blood was: 20.6 ± 0.3 hours after a dose of 10 mg/kg body weight, and 16.1 ± 1.6 hours after a dose of 50 mg/kg body weight.

Toxicity Summary
Identification and Uses: Acetamide is a solid. It can be used as a solvent and stabilizer, an accelerator for bilirubin assays, an antidote for monofluoroacetamide poisoning, and a paper humectant. Human Exposure and Toxicity: No relevant data are currently available. Animal Studies: When acetamide was added to the diet at a concentration of 5%, two rats were randomly selected each week and transferred back to the control diet. After 14-40 weeks, 22 out of 81 rats developed liver tumors. The acetamide-treated group developed tumor nodules and hepatocellular carcinoma. The incidence, rate of onset, and frequency of metastasis were higher in male rats than in female rats. Compared with acetamide derivatives, acetamide has the lowest teratogenicity and embryotoxicity. Acetamide can induce morphological changes in Syrian hamster embryonic cells without activating metabolism. Ecotoxicity Studies: Acetamide exhibits selective damaging effects on Entosiphon sulcatum.

---

Toxicity Data
LC50 (Rat) = 16,000 ppmInteractions
Forty male Wistar rats in each of the two groups were fed diets containing 2.5% acetamide or 2.5% acetamide + 5.6% L-arginine, respectively. Fifteen male rats in each of the other two groups were fed diets containing 5.6% arginine glutamate or a control diet, respectively, for one year. Among the eight rats fed acetamide, two developed hepatocellular carcinoma. After one year of acetamide feeding, seven out of sixteen rats developed hepatocellular tumors after continuing to be fed the control diet for three months. In contrast, one out of eleven rats treated with acetamide + arginine glutamate for one year and then on a control diet for three months developed hepatic nodules. No hepatocellular tumors were observed in the control group or the rats fed 5.6% arginine glutamate alone.

---

Non-human toxicity values
Oral LD50 in rats: 7000 mg/kg
Intraperitoneal LD50 in rats: 10300 mg/kg
Subcutaneous LD50 in rats: 10000 mg/kg
Intravenous LD50 in rats: 12500 mg/kg
For more non-human toxicity values (complete data) for acetamides (9 types in total), please visit the HSDB record page.

[1]. Acetamide. IARC Monogr Eval Carcinog Risks Hum. 1999;71 Pt 3:1211-21.

[2]. The food contaminant acetamide is not an in vivo clastogen, aneugen, or mutagen in rodent hematopoietic tissue. Regul Toxicol Pharmacol. 2019 Nov;108:104451.

[3]. Acetamide derivatives with antioxidant activity and potential anti-inflammatory activity. Molecules. 2010 Mar 23;15(3):2028-38.

According to the International Agency for Research on Cancer (IARC) of the World Health Organization, acetamide is a possible carcinogen. Acetamide is a colorless crystal with a musty odor (NTP, 1999). It has low toxicity. Acetamide is an acetamide compound formed by the condensation of acetic acid and ammonia. It is a monocarboxylic acid amide, belonging to the N-acylamine class of compounds. It is a tautomer of acetilimic acid. Acetamide is mainly used as a solvent and plasticizer. Workers in the plastics and chemical industries may be exposed to it. Acute (short-term) exposure can cause mild skin irritation. Currently, there is no information on the chronic (long-term), reproductive/developmental, or carcinogenic effects of acetamide on humans. The U.S. Environmental Protection Agency has not listed acetamide as a carcinogen. Acetamide has been reported in Convolvulus erinaceus, Haplophyllum acutifolium, and other organisms with relevant data. Acetamide is a mineral with the chemical formula CH3CONH2. Its corresponding International Mineralogical Association (IMA) number is IMA1974-039, and the IMA symbol is Ace. Acetamide is found in red beets. Acetamide (or acetate amide, acetamide), with the chemical formula CH3CONH2, is an amide of acetic acid, and in its pure state, it is a white crystalline solid. It is prepared by dehydration of ammonium acetate. Studies have shown that acetamide has antibacterial, anti-inflammatory, anti-arthritis, and antibiotic activities. Acetamide belongs to the primary carboxylic acid amide class of compounds. These compounds contain a primary carboxylic acid amide functional group, with the general formula RC(=O)NH2 (A3310, A3311, A3311, A3312). Acetamide is a metabolite found or produced in Saccharomyces cerevisiae.

---

Therapeutic Uses
/EXPL THER/ /The purpose of this study is/to observe the effects of fluoroacetamide on rat cardiomyocytes and the detoxification effect of acetamide. SD rats were divided into four groups and administered different doses of fluoroacetamide (orally), with two groups receiving acetamide (intraperitoneally). Changes in cardiomyocytes and serum AST, LDH, CK, CK-MB, and HBDH were detected at different time points after poisoning. In the group administered 8 mg/kg fluoroacetamide, compared with the control group ((187.70 ± 46.87), (755.65 ± 498.90), (347.25 ± 228.40) U/L, respectively), the serum AST [(589.58 ± 821.72) U/L], CK [(916.78 ± 343.55) U/L], and HBDH [(504.47 ± 148.88) U/L] of mice administered 4 mg/kg body weight of fluoroacetamide were significantly increased (p<0.01). Twenty-four hours later, pathological changes such as degeneration, liquefactive necrosis, and inflammatory cell infiltration were observed in the myocardial tissue. All male mice died within 3 days. Five days later, the serum LDH and HBDH levels in mice treated with fluoroacetamide at 4 mg/kg body weight were significantly higher than those in the control group (p<0.01). On day 10, myocardial enzymes in all experimental groups returned to normal, but some interstitial fibroblast proliferation was observed. The pathological changes in the group treated with acetamide (100 mg/kg body weight) were alleviated. Acute fluoroacetamide poisoning can damage cardiomyocytes, while acetamide can alleviate the damage, but the damage is reversible. ...
/Experimental Treatment/ /The purpose of this study/ is to investigate the effects of different doses of acetamide on the expression of inhibitory amino acids (γ-aminobutyric acid, GABA) and excitatory amino acids (glutamate, Glu) in the cerebral cortex of rats with acute tetramine (TET) poisoning. Eighty SPF-grade Sprague-Dawley rats were randomly divided into five groups (n=16 per group): a saline control group, a dimethyl sulfoxide (DMSO) control group, a TET exposure group, a high-dose (2.8 g/kg/d) acetamide treatment group, and a very high-dose (5.6 g/kg/d) acetamide treatment group. Rats in the exposure and treatment groups were administered TET by gavage after fasting, followed by intramuscular injection of saline or different doses of acetamide for five consecutive days. Temporal lobe cortical tissue was collected at 3 h, 12 h, 48 h, and 7 days after administration. Immunohistochemistry was used to detect the expression levels of GABA and Glu in the temporal lobe cortex using mean optical density (OD) values. In the TET exposure group, the OD value of GABA began to increase at 12 hours after treatment, peaked at 48 hours, and returned to normal levels after 7 days. In the high-dose acetamide treatment group, the increase in OD value at 12 hours was less significant than in the TET exposure group, and the OD value returned to normal levels after 48 hours, lower than in the exposure group, and its change was closer to that of the control group. In the ultra-high dose acetamide treatment group, the OD value began to increase significantly after 3 hours and was significantly higher than that in the TET exposure group (p<0.01), peaking at 12 hours and returning to normal levels after 48 hours. …In the tetracycline exposure group, the glutamate (Glu) optical density value was significantly lower than that in the two control groups at 3 hours after treatment, gradually increasing from 12 to 48 hours, and returning to normal levels on day 7. The changes in the high dose acetamide treatment group were similar to those in the tetracycline exposure group, but closer to the control group after 48 hours; the glutamate optical density value in the ultra-high dose acetamide treatment group was significantly higher than that in the tetracycline exposure group at 3 hours after treatment (p<0.01), with no significant difference between the two groups at 12 hours; at 48 hours and day 7, the glutamate optical density value in the ultra-high dose acetamide treatment group was significantly lower than that in all other groups (p<0.01). High dose acetamide treatment has a certain therapeutic effect on central nervous system damage caused by tetracycline poisoning, while the effect of ultra-high dose acetamide on neurotransmitter expression is more complex and difficult to assess.

C2H5NO

59.0672

59.037

60-35-5

Acetamide-15N;1449-72-5;Acetamide-d5;33675-83-1

178

White to off-white solid powder

1.0±0.1 g/cm3

78.4±23.0 °C at 760 mmHg

78-80 °C(lit.)

1.2±22.6 °C

62.4±0.3 mmHg at 25°C

1.418

-0.91

1

1

0

4

33

0

DLFVBJFMPXGRIB-UHFFFAOYSA-N

InChI=1S/C2H5NO/c1-2(3)4/h1H3,(H2,3,4)

acetamide

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)

H2O : ~50 mg/mL (~846.45 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

---

Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

View More

Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

---

Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

View More

Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

---

Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

---

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