title: Ethanol patch test: a simple method for identifying the effectiveness of cyanamide in alcoholics.
abstract: BACKGROUND
  To identify the pharmacological effectiveness of cyanamide, 144 alcoholics treated with cyanamide were subjected to a test that used an acetaldehyde dehydrogenase (ALDH) inhibitor, the ethanol patch test, which is considered to be a good indicator of ALDH2 phenotype.
  
  
  METHODS
  We placed 100 microl of 70% ethanol on a lint pad and, as a control, placed the same volume of distilled water on a second pad. The ethanol patch test was performed on 144 alcoholics more than 2 weeks after abstinence from alcohol before and after treatment with cyanamide for 1 week. The dose of cyanamide was increased up to 150 mg until the patch test yielded a positive result.
  
  
  RESULTS
  In the ethanol patch test, 36 alcoholics (25.0%) gave a positive result before treatment with cyanamide and might have been ALDH2(1)/2(2) heterozygotes. Among 108 alcoholics who were not positive, the distribution of the cyanamide dose that yielded a positive ethanol patch test result was 30 mg in 42 cases (38.9%), 50 mg in 33 cases (30.6%), 70 mg in 5 cases (4.6%), 100 mg in 6 cases (5.6%), and 150 mg in 2 cases (1.9%). Prevalence of liver cirrhosis was significantly higher in alcoholics who showed a positive ethanol patch test result at doses of less than 50 mg cyanamide than those at doses more than 70 mg (p = 0.029). The prevalence of adverse effects was significantly higher in alcoholics who showed a positive ethanol patch test result at doses of more than 70 mg than at doses of less than 50 mg cyanamide (p = 0.002).
  
  
  CONCLUSIONS
  The ethanol patch test is a useful method for identifying pharmacological effectiveness of cyanamide and may reduce the prevalence of side effects in cyanamide-treated alcoholics.
authors.affiliation: Tokyo Medical Center of Alcohol Related Disabilities, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamauchi
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.forename: K
authors.initials: K
authors.lastname: Takeda
authors.forename: K
authors.initials: K
authors.lastname: Sakamoto
authors.forename: M
authors.initials: M
authors.lastname: Ohata
authors.forename: T
authors.initials: T
authors.lastname: Tabe
authors.forename: K
authors.initials: K
authors.lastname: Nakano
authors.forename: S
authors.initials: S
authors.lastname: Fujiwara
authors.forename: Y
authors.initials: Y
authors.lastname: Takao
authors.forename: G
authors.initials: G
authors.lastname: Toda
mesh_terms: D000328:Adult; D000368:Aged; D000437:Alcoholism / Q000188:drug therapy*; D000444:Aldehyde Dehydrogenase / Q000037:antagonists & inhibitors* / Q000235:genetics; D003484:Cyanamide / Q000008:administration & dosage / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D000431:Ethanol; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D010328:Patch Tests
chemical_list: D004791:Enzyme Inhibitors; D000431:Ethanol; D003484:Cyanamide; D000444:Aldehyde Dehydrogenase