Contents

Respiration in a nutshell - start here!

Deep dive - the science behind a healthy coat and skin

1. Intro
2. A quick word on inhalers
3. From COPD to equine asthma
4. The Gut:Airway connection
5. The forage factor
6. Why meadow hay matters
7. Pollens
8. The How&Why behind pollens
9. The bigger picture - histamine intolerance
10. Coughing
11. Chronic ongoing coughing
12. The haylage misunderstanding
13. What to do
14. Immunity begins in the gut
15. Nature's supportive therapies
16. The 3-amigos - detox & defence
17. In summary
18. Sources

Respiration in a nutshell – start here

Breathing shouldn’t be hard work - but for many horses, dust, pollens, feed allergens, and even gut imbalance can make every breath a struggle. The respiratory and digestive systems are more closely connected than most people realise: when the gut is inflamed, the lungs often react too.

In short? A healthy gut = calm immunity = clear, easy breathing.

Does this sound like your horse?

• Seasonal headshaking, nasal discharge, or runny eyes
• Wheezing, coughing, or heavy breathing in humid or dusty weather
• Rubs face or eyes, restless during pollen season
• Sluggish energy or lethargy in hot, humid air
• Sensitive to hay, bedding, or stable dust
• Recurrent coughs or “can’t quite shake it off”

Why it happens

The modern horse lives in an environment their body wasn’t designed for - enclosed spaces, dust, mould, pollens, haylage fermentation, and nutrient-poor soils all strain the respiratory and immune systems.

At the same time, the gut biome can become disrupted (hindgut dysbiosis or “leaky gut”), which sends inflammatory signals through the body - including to the lungs.

When the gut and liver are struggling, histamine levels rise and allergic reactivity takes over, leading to coughing, headshaking, or airway inflammation.

First steps & natural support

• Start with clean, stemmy, meadow hay - avoid haylage and rich pasture.
• Feed a low-starch, high-fibre diet and ensure minerals are balanced (see EquiVita / VitaComplete).
• Hydrate and move daily to keep the lymphatic “drainage” system flowing.
• Support the gut first before addressing the lungs...
• ... then add targeted respiratory herbs – PollenTonic, BreathePlus, or KoffTonic – to soothe airways and support clear breathing.
• Avoid haylage and inhaled steroids if possible; they can add extra strain on the gut:liver pathway.

🚩 Respiration red flags - watch for:

• Laboured breathing, flared nostrils, or abdominal effort.
• Coughing with nasal discharge or temperature.
• Sudden fatigue or loss of appetite in pollen season .
• Chronic cough unresponsive to medication.
• Repeated steroid use or inhaler dependence → discuss long-term adrenal and immune implications with your vet and consider supportive herbal options.

Bottom line

Respiratory issues are rarely 'just in the lungs.' They’re often the body’s way of saying the gut and immune systems need help. When we nourish from within - clean forage, balanced minerals, and calm detox pathways - the lungs can do what they were designed to: breathe easy, strong, and free.

Next step?

Explore our Respiration / Pollens product range to help bring your horse back into balance

Meanwhile...

Want the full equine respiration science and support plan? Here's our Deep Dive for the gut:ung connection, the truth about haylage, and the herbs that help horses breathe easier year-round.

Deep dive: the science behind equine respiration

Principal Body System: Respiratory

Definition: The lungs and a series of associated passageways leading into and out of them

Function: Supplies oxygen; eliminates carbon dioxide, helps regulate the acid-base balance of the body

The equine respiratory system is geared for athleticism. With a huge lung capacity to enable air-intakes of up to 1800-litres/minute in a galloping horse, up to 300-litres of blood are pumped at high pressure at full gallop through tiny lung capillaries surrounding 10-million air-sacs, to take up and deliver over 70-litres of oxygen, per minute, to the working muscles.

Phew!

As a result, any related condition that reduces efficiency of oxygen uptake from the air sacs can significantly influence a horse's athletic capacity. As fate would have it, in domesticity the equine respiratory system is continually being challenged from the external environment, i.e. stable moulds/allergens, school surfaces, dusty bedding, pollens, feed - you name it, our horses will breathe it in.

Seasonal allergies are something most of us can relate to - whether we experience them ourselves or see them in our horses. They’re rising in prevalence too. Allergies develop when the immune system overreacts to everyday substances in the environment, producing antibodies that trigger mast cells to release histamine. The result? Those all-too-familiar signs like rubbing, headshaking, runny eyes, nasal discharge, and general irritation.

Conventional treatments may help reduce symptoms temporarily, but they often include inhalers/steroids which can be detrimental to the immune system, and most importantly, don’t address the root cause of the immune dysregulation.

A quick word on inhalers

Here's a thing - inhalers are steroids. You take the inhaler - you flood the body with steroids. And their purpose? To mimic the body’s own adrenal hormones, particularly cortisol, the key stress hormone released during the fight/flight response.

When the body goes into survival mode, cortisol widens (dilates) the bronchial passages, increases blood flow to the muscles (ready to “Run Now!”), and sharpens focus by sending oxygen to the brain. Pupils dilate for tunnel vision to stay focused, and the lungs open up to take in more oxygen to sustain the 'flight'.

However, when steroid inhalers are used long-term, they can cause side effects by disrupting the endocrine and central nervous systems, placing strain on the adrenal glands. In many cases, it’s far kinder to the body to support airway health naturally, using herbs traditionally known to help open the lungs and ease breathing - such as Eyebright (Euphrasia officinalis) and Liquorice Root (Glycyrrhiza glabra).

• Eyebright has long been used to help tone and soothe mucous membranes in the eyes and respiratory tract, supporting clear, calm airways.
• Liquorice Root, meanwhile, is valued for its natural saponins and soothing demulcent properties, helping to protect irritated tissues while gently supporting adrenal balance.

Together, they offer a natural, holistic way to nurture the respiratory system without burdening the body’s own stress response.

From COPD to equine asthma

Back in the good old days, COPD was the only respiratory term we really heard - typically thought of as a winter problem when horses spent long hours stabled. Fast forward to today, and we’re seeing allergen-driven (autoimmune) reactions cropping up all year round. Spring tree pollens can trigger histamine-related sensitivity, while summer’s hot, humid conditions bring grass pollens that can lead to deeper airway congestion and irritation.

This summer pasture allergen response occurs because warm, humid air traps and carries more pollen particles, leading to higher pollen counts. Add in hot, dry dust and heat-loving mould spores, and the respiratory load increases even further. All of this puts extra strain on the body’s natural filtration and detoxification systems - the liver, kidneys, and lymphatics - as these three amigos work tirelessly to process and clear the toxin congestion, helping the body excrete the build-up of allergens and waste products.

And just like us humans, some horses react and some don’t - and there’s a reason for that; see our Blog - Reversing autoimmune disease. For those that do react, the experience can be frustrating and exhausting. Whether horse or human, respiratory pollen allergies can become a truly debilitating syndrome that causes real discomfort and distress.

* What was once called COPD is now recognised under the broader umbrella of Equine Asthma, covering everything from mild, seasonal allergy flare-ups to chronic airway inflammation. The triggers may change with the seasons - dust, spores, pollen, or even stress - but the goal remains the same: keeping the respiratory system calm, clear, and resilient year-round.

The gut:airway connection

From Traditional Chinese Medicine (TCM), we’ve long known that the hindgut and lungs belong to the same element - metal. Interestingly, recent research (2020) took a much closer look at the hindgut and found a clear physiological link between the gut and airway systems. The study showed that when the hindgut microbiome’s integrity - and therefore its function - becomes compromised, horses are far more prone to chronic cough issues. Start repairing the hindgut microbiome, and the airways begin to recover too. (See our KPU page for the full story on this connection.)

* Modern science is now confirming what traditional systems like TCM have said for centuries - that gut and lung health are intertwined. A stressed or 'leaky' hindgut can trigger systemic inflammation that reaches the lungs, while a balanced biome helps maintain a calm, resilient respiratory system. See Sources  at the bottom of this page.

There’s plenty we can do to help the gut biome regenerate a healthy balance of beneficial microbes. If dysbiosis (microbial imbalance) or leaky gut is present, a gentle gut clean-up can help weed out the harmful bacteria and encourage repopulation of friendly flora.

Restoring microbial diversity brings wide-reaching benefits - not just for digestion, but for immunity, skin health, and the respiratory tract too.

The forage factor

Equally, the forage we feed has a huge impact on the wellbeing of those vital hindgut fibre-fermenters. The horse is, quite literally, a hindgut, grass-forage, fibre-fermenting machine - and that fibre is found only in the stems of grasses that have been allowed to grow long enough to produce seed heads. In contrast, our short, neon-green UK pasture provides almost no true fibre in those lush leaves.

Haylage is even more problematic. To turn cut grass into haylage, lactic acid bacteria (the same type used for pickling onions or red cabbage) naturally ferment it. When eaten by the horse, those lactic acid bacteria enter directly into the hindgut - and this can quickly lead to hindgut acidosis. Left unchecked, that acidic imbalance can spiral into broader immune dysfunction and, in chronic cases, autoimmune syndromes.

• Forage that’s too rich, too short, or too fermented can overwhelm the microbial balance in the hindgut. True gut health starts with fibre - the long-stem cellulose and hemicellulose that keep fermentation steady and the microbiome happy. When the gut flora are thriving, the lungs follow suit.

Why meadow hay matters

Quality meadow hay is the best forage we can offer our horses. Ideally, it’s cut from long, mature, stemmy grasses - those fibrous stems provide the cellulose and hemicellulose that horses are designed to digest. It’s what their ancestors grazed on as they roamed miles of open grassland, foraging not only long grasses but also herbage, fruits, nuts, berries, bark, and mosses for natural prebiotic diversity.

In a perfect world, our horses would have access to nothing but quality meadow hay, full of diverse grass species, 24/7 - plus hedgerows and natural herbage to browse on for seasonal variety and self-selection. This kind of steady trickle-feeding of clean, dust-free forage keeps the gut biome balanced and supports healthy airways, buffering the respiratory system from dust and spores that can irritate sensitive lungs.

Food for thought - quite literally. It’s always worth checking your feeding regime, from feedbowl to forage. We've got this all covered in our Feeding Our Horses Healthy section in the Advice Centre (main navigation bar above), and specifically the sub-chapter, Why what we feed has to be right.

Pollens

We’ve had our fair share of allergic reactions in our herd over the years, but it was our elderly show cob, Kelso, who taught us the most.

Kelso had a chronic allergy response to just about everything life could throw at him. He battled chronic sweet itch, was a violent headshaker during the spring tree-pollen season, and when the humid summer grass-pollens hit, he literally couldn't breathe.

His respiratory system was permanently compromised - if we were out hacking and I mistimed it (I always tried to go out first thing while the air was still cool), I’d have to dismount so he could bury his face into my back for the walk home, trying desperately to block the irritants from reaching his nostrils.

Come summer, we had to bring him in during the day to escape the humidity, turning him out only at night when the air was cooler - always in a full-face mask and nose-net. Over the years I learned to manage his symptoms, but I never truly understood the how and why behind them until I began studying Functional Medicine, which sadly wasn't until after he'd passed.

It was Kelso - and our desperate need to find something that truly worked - that inspired the creation of EquiNatural (read his full story in the About Us/Our Story section above). Every horse teaches us something, and Kelso’s legacy taught me that chronic allergy responses are a sign of systemic imbalance involving the immune system, gut health, and detox pathways. If only I knew then - while Kelso was still with us - what I know now... when we treat the horse as a whole, real improvements begin to happen.

The 'How&Why' behind pollens

A chest infection is easy to grasp — bacteria or viruses invade, multiply, and cause illness. But a pollen allergy is a very different story. It’s not an 'infection' at all, but an overreaction of the immune system. (Recent science, though, reveals it’s part of an even bigger picture — more on that in a moment.)

While it’s tempting to seek quick relief through antihistamines, inhalers, steroids, or as some vets suggest - even antibiotics, these can bring side effects and unintended consequences. Pollens aren’t bacteria - yet antibiotics will damage the microbiome, suppress the immune system, and add to the body’s toxic load. In the long term, this only weakens the system further and fails to address the root cause.

We all know that the immune system’s job is to defend against infection, toxins, and other invaders. But in an allergic response, the 'invader' isn’t actually harmful - the immune system has simply lost its ability to distinguish friend from foe. The army of white blood cells is sent to fight something it shouldn’t, and the result is inflammation, irritation, and the familiar misery of seasonal allergy symptoms.

The bigger picture - histamine intolerance

Now to that “Much Bigger Picture” - histamine intolerance. Recent research shows that excessive histamine activity can intensify a wide range of already-established health syndromes in both humans and horses.

In balance, histamine is our friend. It’s part of the body’s normal defence process, helping to remove what’s bothering it - like the club bouncer on the door, keeping troublemakers out. Histamine helps flush out irritants from the body or off the skin.

However, in our modern environment, histamine intolerance has become a Big Thing. Too much histamine is being produced or not broken down efficiently, triggering reactions on its own and making the body feel, frankly, dreadful. Symptoms can range from swelling and fluid retention to fatigue and inflammation - it’s one reason why so many owners notice puffy leg swelling during pollen season (more on that later).

Histamine intolerance is now recognised as a spectrum disorder, with levels varying from mild to severe. Understanding where a horse sits on that spectrum can be key to managing allergic responses effectively. It's not just about too much histamine - it’s about how the body metabolises and clears it. Nutrient cofactors like vitamins B6 (P5P), along with certain flavonoids, help the body’s natural DAO (diamine oxidase) enzymes break histamine down, so supporting these pathways nutritionally can make a real difference to how both horses and humans handle seasonal reactions.

For the full deep dive, see our blog Histamine Intolerance – The New Kid on the Block.

Coughing

Coughing is a perfectly normal, healthy reflex — it's the body’s way of clearing the airways of irritants such as dust, spores, and bacterial or viral microorganisms. The lungs secrete mucus as a natural defence mechanism, and coughing helps to expel that mucus along with any unwanted hitchhikers.

Sadly, there’s not a lot we can do to prevent these microorganisms from getting in there, but what we can do is help the body shift them out before they replicate and turn into infection.

It’s that cough reflex that agitates and moves mucus up from the lungs, so it’s never a good idea to suppress it. Instead, we should be supporting expectoration - the body’s capacity to bring mucus up efficiently - because it’s a vital part of the clearing process.

Coughing is actually a healthy sign that the body is doing its job, and we can help it work better. Hydration, gentle herbal expectorants, and respiratory support can all make the process smoother, keeping the lungs clear and comfortable. See our  KoffTonic in the Shop link at the bottom of this page.

Chronic ongoing coughing

If your horse has a persistent cough that doesn’t respond to medication and isn’t obviously allergy-related, it’s time to ask: why is my horse doing this?

The wild horse evolved in dry, dusty environments, and today's modern domesticated horse is equally equipped to handle them. Under normal circumstances, the airway’s cellular lining (the epithelium) is protected by a thick mucus layer that traps dust and shifts it back out — no coughing required.

To build and maintain this mucus layer, the body needs cysteine, an amino acid that contains sulphur. And to produce enough cysteine, the horse must have an adequate supply of sulphur in the diet. Here’s where things can go wrong — especially in cases of KPU (Cryptopyrroluria).

When KPU is present, the horse becomes sulphur-deficient. Without enough sulphur, the airways can’t produce cysteine, meaning the protective mucus layer can’t form properly. The result? A dry, irritated airway that can’t trap dust - so the horse coughs.

The haylage misunderstanding

One common and well-meaning response to a coughing horse is to switch from hay to haylage - after all, it’s dust-free, right?

Well, yes… but here’s the catch. Haylage undergoes fermentation, introducing lactic acid bacteria that can upset the delicate balance of the hindgut microbiome.

Since the microbiome directly governs immune function, this disturbance can set off a cascade of secondary reactions: heightened sensitivity to moulds, pollens, insect bites, and other allergens. What starts as an attempt to ease coughing can actually fuel the underlying problem.

This is why it’s vital to trace symptoms back to their root cause. Chronic coughing is often secondary to deeper metabolic or gut-based issues. Hindgut dysbiosis can disrupt vitamin B6 activity, impair liver biotransformation, and ultimately lead to KPU - setting off a chain reaction that manifests through the airways.

For a deeper understanding, see our KPU page, where this connection is explained in full.

What to do

Taking the functional approach, we first need to ensure the immune system is as robust as possible - and that means also toning the lymphatic system, upon which the lungs (and the skin and brain) rely to drain toxins away.

The lymphatics are deeply connected to the Big Picture. When the body experiences an allergic reaction and the immune system isn’t functioning optimally, the lymph nodes can become overburdened and swollen. This slows lymphatic drainage, allowing congestion and inflammation to linger rather than being cleared effectively.

* Think of the lymphatic system as the body’s internal “drainage and detox” network. Gentle movement, hydration, and certain herbs — such as cleavers, calendula, and nettle - help keep lymph flowing freely, supporting both lung and immune health.

Immunity begins in the gut

Immunity starts with the gut - specifically, the gut microbiome, where many of the body’s immune cells are both created and housed. Keeping this microbial ecosystem balanced is vital. An inflamed or imbalanced gut won’t keep the immune system strong enough to fend off potential allergens.

As the saying goes, “Take out the bad and put in the good.” Start by reviewing your feeding regime - from feedbowl to forage - as dietary triggers often underlie chronic inflammation and allergy sensitivity.

Key steps to consider:

• Eliminate common feed triggers such as wheatfeed, corn, soy, alfalfa, GMO ingredients, and artificial additives. See our Feedbowl page for more details on these pro-inflammatory fillers.
• Feed a clean, high-fibre, very low-carb diet with anti-inflammatory omega-3 plant nutrients such as linseed.
• If you’re feeding haylage, consider switching back to clean, quality hay.
• Check for environmental factors such as pesticides, chemicals, pollution, or mould exposure — is there local crop-spraying nearby?
• Consider whether chronic infections (viruses, bacteria, yeasts, or parasites) might be contributing.
• If your horse has recently been on antibiotics, bute, or other medications, follow up with a gentle detox.
• Reduce stress and ensure plenty of rest — a stressed, fatigued horse is more prone to gut stress and glandular (pyloric) ulcers.

Nature’s supportive therapies

Thankfully, nature provides an incredible range of herbal therapeutics that can truly help. First, we address the symptoms:

• For nasal catarrh, we use anticatarrhals to help clear congestion.
• For itching, antipruritics soothe and calm the skin.
• For inflammation, anti-inflammatories with cooling, astringent properties help tighten and tone tissues.
• For histamine sensitivity, natural antihistamine herbs can bring gentle support.
• For stress, we include nervines to calm the system without sedation.

Then we go deeper - to the root cause. When the body is overproducing histamine and the immune system is overreacting, we need to normalise rather than suppress. That’s where adaptogens come in: herbs that help regulate the immune response and restore internal balance.

* Adaptogens such as ashwagandha, schisandra, and astragalus don’t push the immune system up or down - they teach it to regulate itself. Combined with anti-allergenic herbs like nettle and yarrow, they can help calm the runaway immune activity behind seasonal and respiratory flare-ups.

The three amigos - detox and defence

For the all-important lymphatic system - together with the liver and kidneys (the body’s “three amigos”) - gentle detox support may be needed to clean-out and reset the filtration system. Keeping these organs working in harmony helps the body eliminate allergens, waste, and excess histamine more efficiently.

Vitamin E and selenium are also powerful antioxidants that play a crucial role in protecting upper respiratory tissues and lung function — both are included as standard in our EquiVita  and VitaComplete mineral solutions.

In summary

Coughing, allergies, and airway irritation rarely happen in isolation - they’re the body’s way of waving a flag that something deeper needs attention.

Whether it’s a dry airway from sulphur deficiency, a stressed gut biome from haylage, or immune confusion linked to KPU, the message is the same - look beyond the symptom. When we support the gut, the liver, and the body’s natural detox systems, the airways often follow suit - calmer, clearer, and better able to do what nature designed them to do.

A healthy respiratory system starts far beyond the lungs. It begins with clean forage, balanced minerals, a strong microbiome, and a steady, stress-free lifestyle. Get those foundations right, and you’re not just fighting the battle - you’re winning the war.

Click on the SHOP link below to explore our Respiration / Pollens product range.

Sources

• The Microbiota and Equine Asthma: An Integrative View of the Gut–Lung Axis. This review explores the connection between gut microbiota and airway/respiratory disease in horses. MDPI
• The Gut Microbiome of Horses: Current Research on Equine Enteral Microbiome. A broader overview of equine hindgut microbiome research, which lays foundational knowledge for how gut health links to systemic issues (including immunity that may influence lungs). BioMed Central
• University of Surrey’s “Horse Microbiome Research Group” project page. Researching the link between gut and respiratory microbiomes in horses. University of Surrey
• Leduc, L., Costa, M., & Leclère, M. (2024). The Microbiota and Equine Asthma: An Integrative View of the Gut–Lung Axis. Animals, 14(2), 253. https://doi.org/10.3390/ani14020253 MDPI+1. A focused review linking gut microbiome disturbances and airway disease in horses. Contains sections on how gut dysbiosis may contribute to chronic cough/airway inflammation.
• University of Surrey. (2024 – 2028). Microbiome of the Equine Gut and Respiratory Tract: Associations Between Bacterial Communities in Different Body Compartments and Animal Health. Research Project Overview. University of Surrey. A current research project looking explicitly at gut ↔ lung microbial cross-talk in horses.
• Fowler, S. (2023). “Factors Affecting Equine Asthma and the Gut–Lung Axis.” KER Equine News. Ker. A summarised review for practitioners outlining how gut-derived metabolites (e.g., SCFAs) may influence airway inflammation.