While nothing has been shown to stop bleeding, only two things have been proven to reduce bleeding:
FLAIR Strips and Lasix, a drug generically known as furosemide, which is a diuretic. FLAIR Strips are drug-free and have been proven to be as effective as Lasix in reducing lung bleeding during high intensity exercise. FLAIR Strips work by helping to prevent the Pulmonary Capillary Membrane from rupturing.
When Lasix is given to horses, the kidneys produce more urine than normal, which removes water from the blood, reducing the volume of plasma (the watery part of the blood as opposed to the red blood cells) in the circulation. Since Lasix is a systemically administered drug, it reduces blood volume throughout the body, not just the lungs, causing dehydration, weight loss, and electrolyte loss.
Unlike FLAIR Strips, Lasix is a drug, and with repeated use of most drugs tolerance usually develops. Over time you have to use larger doses to get the same results. In contrast, the mechanical support provided by FLAIR Strips is more likely to be equally effective each time it's used without any undesirable side effects.
*”Lasix” is trademark owned by Sanofi-Aventis Deutschland GmbH for the generic drug furosemide. More recently the trademark name used for the equine version of the drug has been “Salix” which is owned by Intervet, Inc. Because the name Lasix has historically been used when referring to the drug for horses, it's the name many recognize and so we use it here.