Suggested withdrawal times and threshold concentrations of therapeutic medications

Detection of a therapeutic substance at concentrations higher than the reported threshold will result in sanctions, according to the Mid-Atlantic Uniform Medication and Testing Program. (LOD = level of detection.)

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Drug

Dose/Route

Withdrawal (no pre-race treatment within)

Threshold

Acepromazine 0.05 mg/kg IV (single dose) 48 hours 10 ng/ml HEPS (applicable metabolite) in urine Betamethasone 9 mg IA only—1 joint 7 days 10 pg/ml of plasma or serum Butorphanol 0.1 mg/kg IV (single dose) 48 hours 300 ng/ml of total butorphanol in urine, or 2 ng/ml of free butorphanol in plasma Clenbuterol 0.8 µg/kg PO twice daily 14 days 140 pg/ml of urine or LOD in plasma or serum Dantrolene 500 mg PO 48 hours 100 pg/ml 5-hydroxydantrolene in plasma or serum Detomidine 40 µg/kg single sublingual dose 72 hours LOD in plasma or 1 ng/ml of carboxydetomidine in urine Dexamethasone 0.05 mg/kg IV, IM, PO 72 hours 5 pg/ml of plasma or serum Diclofenac (topical) 5-in ribbon topically 48 hours 5 ng/ml of plasma or serum DMSO PO, IV 48 hours 10 µg/ml of plasma or serum Firocoxib 0.1 mg/kg PO daily for four days 14 days 20 ng/ml of plasma or serum Flunixin 1.1 mg/kg IV single dose 24 hours 20 ng/ml of plasma or serum Furosemide Maximum 500 mg IV single dose 4 hours 100 ng/ml of plasma or serum Glycopyrrolate 1 mg IV single dose 48 hours 3 pg/ml of plasma or serum Ketoprofen 2.2 mg/kg IV single dose 24 hours 10 ng/ml of plasma or serum Lidocaine 200 mg SC 72 hours 20 pg/ml of total 30H-lidocaine in plasma Mepivacaine 0.07 mg/kg SC single dose 72 hours 10 ng/ml of total hydroymepivacaine in urine or LOD in plasma Methocarbamol   0.15 mg/kg single dose IV or 5 g orally 48 hours 1 ng/ml of plasma or serum Methylprednisolone* (IA only) 100 mg—1 joint 21 days* 100 pg/ml in plasma or serum Omeprazole 3.9 mg/kg PO single dose 24 hours 1 ng/ml of urine Phenylbutazone (IV only) 2.2 mg/kg IV single dose 24 hours 2 µg/ml of plasma or serum Prednisolone 1 mg/kg PO 48 hours 1 ng/ml plasma or serum Procaine penicillin** IM Entry** 25 ng/ml of plasma Triamcinolone acetonide 9 mg IA—1 joint 7 days 100 pg/ml of plasma or serum Xylazine IV 48 hours 0.01 ng/mg of plasma or serum

*Methylprednisolone following intraarticular administration of 100 mg can be detected at 100 pg/ml for up to 21 days. Its use is therefore problematic.

**Mandatory six-hour surveillance of horse prior to post. Administration mush be reported to commission.