Painkillers Difficult to Trace in Horse Meat Although horse meat at the dinner table is a staple protein in many countries, the scandal over its inclusion in "beef" products is growing in the British Isles and other European countries. Now the British Veterinary Association, in this video on The Guardian's Web site, raises the alarm that phenylbutazone, an anti-inflammatory painkiller regularly dispensed to horses, has entered human food products because tracing systems aren't working efficiently. Concern has grown after a line of frozen beef lasagna meals -- produced under the Findus brand -- was found to contain horse meat.