Bute (phenylbutazone) is not a performance enhancing horserace medication. It is used as a "pain killer" for horses that are of the cheaper variety. Trainers who put winning before the health of their horses  will often use Bute to numb a horse to pain of an injury so it can continue to race when it should be rested for healing. This is a common horserace medication that is a factor in many breakdowns at the lower levels of racing.

  Lasix  (furosemide) is a powerful diuretic that causes fluids in the horse's body tissues to be released in the urine. This has the effect of lowering the horse's blood pressure that allows the horse's performance to return to the normal level.

  Some people think that Lasix is a horse upper - this is not true. In some cases, it has a stimulating effect and improves performance, but generally it does not extend ability beyond what it normally is.

  There is only one major side effect of the horserace medication Lasix - excessive urination. Horses on Lasix can lose as much as twenty pounds, giving them a weight advantage. Sometimes Lasix is used as a "cover up" for illegal drugs which can be easily flushed out of the horse's system.

  Many handicappers swear by the "1st time Lasix" angle. The common belief is that horses will either run their best race...or worst race. The best 1st time Lasix play is on a horse that has shown early speed then tired after a half mile. These horses are likely suffering from the effects of bleeding, and will be helped by Lasix. Thoroughbreds that show little or no early speed in their recent races seldom improve with Lasix.  Horserace medication continues to be allowed in only certain racing venues.

  At the venues that allow the medications, enforcement is somewhat varied.  As a rule, if a horse has a bad test, the trainer will be suspended for a period of time, and could be subject to a fine.  The owner would have to return any purse money that was involved.  These decisions are always made by the track stewards.