EIPH & The Price Of Victory: Protecting Racehorse Lungs

The Heart-Lung Mismatch

Selective breeding has produced powerful hearts capable of pumping over 75 gallons of blood per minute at peak exertion, with heart rates soaring up to 220 beats per minute. However, the lungs have not evolved at the same pace. To keep up with oxygen demands, the spleen releases additional red blood cells to enhance oxygen transport. While this “blood doping” boosts performance, it also thickens the blood, increasing lung blood pressure up to four times its resting level—putting immense strain on fragile lung capillaries.

Underlying cardiovascular issues, such as arrhythmias (e.g., atrial fibrillation), valve leakage, or poor heart muscle relaxation, further disrupt blood flow and elevate pulmonary arterial pressure, increasing the likelihood of EIPH.

Breathing Under Pressure

At a gallop, a horse's breathing is synchronised with its stride—drawing in 120–140 breaths per minute. As obligate nasal breathers, all airflow must pass through the nostrils and down an exceptionally long trachea. This forceful inhalation creates a vacuum effect, pulling air in but also partially collapsing the nasal passages and trachea, increasing airway resistance, and amplifying stress on the pulmonary capillary membrane—leading to EIPH. The longer and faster the exertion, the more severe the bleeding becomes.

Compounding this challenge, upper airway obstructions—such as dorsal displacement of the soft palate (DDSP), laryngeal hemiplegia (“roaring”), soft tissue instability, and airway masses—further restrict airflow. Increased turbulence forces the horse to work even harder to inhale, intensifying stress on lung capillaries and raising the severity of EIPH.

The Impact Of Stride And Shock

Each hoof strike sends shock waves up the limbs into the chest, further stressing the delicate lung capillaries. Blood flow is preferentially directed to the upper and back regions of the lungs—areas most prone to EIPH. Repeated episodes cause vascular remodeling, progressive scarring, iron deposits, and thickened vessel walls, worsening the condition of EIPH over time.

The Role Of Inflammation

Inflammation plays a key role in both the cause and progression of EIPH. When blood enters the lungs, immune cells attempt to clear it, but if overwhelmed, the process remains incomplete. This leads to chronic inflammation, which further raises lung blood pressure, creating a vicious cycle of continued bleeding and damage.

Environmental irritants—such as airborne pollutants, dust, mold, and endotoxins in hay—exacerbate inflammation and mucus buildup, obstructing airflow. Over time, chronic irritation reduces lung elasticity, impairs gas exchange, and increases susceptibility to infections and long-term respiratory complications.

The Silent Progression

One of the greatest challenges of EIPH is its subtle onset. In the early stages, bleeding may be minimal and go unnoticed. However, with each training session and competition, lung damage progressively expands from the back of the lungs forward. Approximately 90% of EIPH-related damage results from the cumulative effects of mild, repeated bleeding over years of training, while the remaining 10% stems from more severe and intermittent episodes occurring during maximal race-day exertion.

Repeated bleeding leads to scarring that alters lung architecture, reducing elasticity and efficiency. Large volumes of blood from acute episodes, coupled with scarring and thickening of the blood-gas exchange regions, resulting in impaired gas exchange. This reduces performance, stamina, and overall race competitiveness—often referred to as “exercise intolerance.”

For elite equine athletes, this oxygen limitation can mean the difference between winning and losing. Moderate to severe EIPH directly impacts race performance, placings, and career earnings.

Flair™ Nasal Strips: A Simple Solution

FLAIR Equine Nasal Strips are the only non-drug, scientifically proven solution to reduce EIPH severity. Since lung damage occurs both during training and racing, FLAIR Strips help minimise harm in both scenarios. Studies show FLAIR Strips are equally or even more effective than Lasix during maximum exercise efforts. In fact, their protective benefits increase as exercise intensity rises, making them a valuable alternative to—or addition to—Lasix.

FLAIR Nasal Strips are approved for racing in Middle East countries, including United Arab Emirates, Qatar, Bahrain, and Saudi Arabia.

Key Benefits Of Flair Strips:

✅ Reduce Airway Resistance – Reduce nasal passage collapse, lowering inspiratory resistance and reducing lung capillary pressure, which lessens EIPH severity.

✅ Enhance Oxygen Consumption – By reducing airway resistance, less effort is needed for breathing, allowing oxygenated blood to be diverted to muscles instead of respiratory effort, conserving energy, increasing exercise tolerance, and delaying fatigue.

✅ Optimise Stride Efficiency – Improved breathing leads to smoother, more powerful strides, maximising speed, coordination, and stamina.

✅ Aid Recovery – More efficient respiratory cooling, allowing horses to recover faster post-exercise.

✅ Reduce Stress & Distractions – Easier breathing keeps horses calmer, more focused, and more confident, leading to more consistent performances.

✅ Protect Long-Term Health – FLAIR Equine Nasal Strips reduce the negative impacts of upper airway obstructions, lower airway inflammation, and EIPH, and may help reduce fatigue-related injuries in tendons, ligaments, and bone, all of which serve in prolonging competitive careers.

Proven Benefits 

Scientific studies confirm that FLAIR Nasal Strips:
✔ Reduce airway resistance
✔ Reduce fatigue
✔ Conserve energy ✔ Reduce EIPH
✔ Quicken recovery post exercise

FLAIR Nasal Strips provide a competitive edge while safeguarding respiratory health for the long haul.

Support Your Horse’s Breathing. And Protect Their Future.