Rules restricting the use of anabolic steroids in racehorses will go into effect in New York as of Jan. 1, the state's racing and wagering board announced on Thursday. The rules, similar to those adopted in more than 20 states this year, will allow the therapeutic use of one of four anabolic steroids as long as they are administered at least 30 days before a race. All other anabolic steroids will be banned. New York is the last of the three states hosting races in the Triple Crown series to formally adopt rules restricting steroids. Both Kentucky, where the Kentucky Derby is run, and Maryland, where the Preakness Stakes is run, passed the rules earlier this year. The four anabolic steroids that will be allowed to be administered are stanozolol, boldenone, nandrolone, and testosterone. Only one will be allowed to be present in a horse's postrace urine sample, as long as its concentration is below a specific threshold level determined to be immaterial to a horse's performance.