A horse trained by Bob Baffert has tested positive for a prohibited medication that is a common ingredient in cough suppressants, adding to a string of post-race positives for the trainer in recent months. According to a complaint posted on the website of the California Horse Racing Board, the horse, Merneith, tested positive for dextrorphan following a second-place finish in the fourth race at Del Mar on July 25. The positive was confirmed in a split-sample test. The complaint does not list the concentration of the drug found in the horse’s system. Dextrorphan is a metabolite of dextromethorphan, a stimulant that is used in over-the-counter cough suppressants. While it is classified among many drugs that have a low potential to impact performance, it carries a higher-class penalty designation because of its ability to impact the central nervous system. Mike Marten, a spokesman for the CHRB, said that Baffert has been assigned a hearing date of Nov. 12. In California, the penalty for a Class B violation is a minimum 30-day suspension “absent mitigating circumstances.” The penalty can be increased to a maximum of 60 days “in the presence of aggravating factors.” Craig Robertson, Baffert’s attorney, said on Tuesday that he will present evidence during the hearing tracing the positive to a groom’s use of two cough suppressants at the time the positive was detected. He said the groom had tested positive for COVID-19, and that after the groom returned to work at the barn, he was taking both DayQuil and NyQuil, which each contain dextromethorphan. “No one would ever intentionally give a cough suppressant to a horse,” Robertson said. Last week, Robertson acknowledged that Gamine, a Grade 1-winning filly trained by Baffert, had tested positive for betamethasone, a corticosteroid, following her third-place finish in the Kentucky Oaks at Churchill Downs on Sept. 4. Robertson acknowledged the positive test after it was reported in The New York Times. A split-sample test has not yet been returned. Earlier this year, Baffert had two horses, including Gamine, test positive after races in Arkansas for lidocaine, a drug in a similar penalty class to dextrorphan. Baffert was handed a 15-day suspension, but he has appealed that ruling, arguing that the horses were inadvertently exposed to lidocaine from a medication patch worn by a stable employee to treat back pain. “Unfortunately, this is a bad string for” Baffert, Robertson said. “But [the dextrorphan] positive is another case of contamination.” Dextrorphan has a complicated regulatory history owing to its ubiquity in human medications and its prior use among some horsemen as a tool to curb cribbing behavior. Its parent molecule, dextromethorphan, can also have stimulant and hallucinogenic effects in high concentrations in humans. In 2017, the Kentucky Horse Racing Commission threw out three positives for dextrorphan after concluding that the concentrations in the cases were “irrelevant” to the horses’ performances. However, at that time, the KHRC had language in its rules that allowed the commission to take into account the potential performance-enhancing effect of many drugs, and that language has since been removed. The updated rulings for Class 4 and Class 5 violations posted to the CHRB's website on Tuesday also included trainer John Sadler being cited for having his older horse Higher Power having phenylbutazone, the legal anti-inflammatory commonly known as Bute, in his system following a workout at Del Mar on Aug. 10. Higher Power on Aug. 22 subsequently finished fourth in the Pacific Classic, which he had won in 2019. He has not raced since, but has been working regularly for a scheduled start Nov. 7 at Keeneland in the Breeders' Cup Classic, for which Sadler said he was be pre-entered. "He worked that morning and was fighting a little bit of a foot afterwards, so we gave him some Bute. Then they came in later in the morning for a random test," Sadler said Tuesday. "It would be like if you got home from a run and couldn't have an aspirin." Sadler said he was informed his hearing into the matter would be before Del Mar's stewards next month. Del Mar's fall meeting opens Saturday. This incident is listed as a Class 4 drug with a Category C penalty, meaning Sadler could potentially receive merely a warning. --additional reporting by Jay Privman An earlier version of this story incorrectly stated that the penalty for a dextrorphan positive mandates the disqualification of a horse.