You’ve likely heard it a thousand times: “I didn’t know my horse was given an illegal substance.” As they say, ignornance is not a defense.
You need to know what might be a “drug.” You can eliminate common “accidental” drug-test positives if you avoid:
• Anything containing poppy seeds, as they’ll give you a narcotics positive.
• Cocoa, chocolate, tea, coffee, cola, most canned sodas and some herbals. These can lead to methylxanthine positives. Methylxanthine compounds include caffeine, theophylline and theobromine.
• Remedies containing belladonna, thornapple, mandrake and henbane, as these can cause a positive for atropine and scopolamine.
• Jimson, a U.S. weed that often invades soybean fields. Like belladonna, it will lead to positives for atropine and scopolamine.
Human herbal sports/performance supplements and “energy” supplements are common causes of equine positives. Most contain high-caffeine herbs. Caffeine can be hiding in places you wouldn’t expect, too, like orange, grapefruit and other citrus flowers.
Drug positives aren’t only due to ingested products. Topical drugs on the horse’s skin can cause positives if they’re absorbed into the blood. The greatest absorption likelihood is where skin is broken, through mucus membranes or if they directly contaminate the sample by being present on the skin where a needle is inserted or around the genital area.
A good online source for detailed chemical information on plants/herbals is Duke’s Phytochemical Database, www.biologie.uni-hamburg.de/b-online/ibc99/dr-duke/. You can search either by plant name or chemical, as well as for activities of individual plants and plants with a specified activity.
That’s not to say that use of the herbs will automatically get you a positive. Even alfalfa contains salicylate, which theoretically could lead to a positive for aspirin.
It depends on the type of chemical that has the action, because positives are called on the basis of searching for and positively identifying specific chemicals, not by plant type. The chemical’s concentration in the herb is also important, of course, but that will always be highly variable.
If in doubt about the legality of a substance, ask your veterinarian or pharmacist or call your sport’s governing body.