What to do if your horse starts coughing?

Part 2 of our series on equine respiratory health

In the first part of this series, we looked at what a cough actually is, how to recognise the different types of cough and what the most common causes are in horses – from dust and viruses to allergies and asthma.

Now that you know why your horse is coughing, it’s time to talk about what you can do next.

In this article, we’ll look at this:

The first practical steps you should take when your horse starts coughing
When it’s time to stop observing and call the vet
What diagnostic tests your vet can recommend
Which treatment options are most effective and when you should use them

Whether it’s a new, unexplained cough or a recurring problem, this guide will help you act calmly, confidently and informed.

Let’s start with the first reaction that every horse owner should know.

First reaction: What to do when your horse coughs

When your horse coughs unexpectedly, it’s often difficult to know what to do first. Follow these practical steps:

✅ Observe closely:
- Does it only happen once, or several times in a row?
- When does it occur – at rest, during exercise, in the stable, after eating?

✅ Look out for other signs:
- Nasal discharge (clear or coloured?)
- Increased respiratory rate or breathing effort
- Change in appetite, behaviour, or energy
- Increased temperature (above 38.5 °C / 101.3 °F)

✅Take notes:
- Keep a brief log of the coughing fits and other symptoms. This will be useful if you need to consult your vet later.

❌ Don’t assume it’s “just dust”.
- Even a single cough can be the first sign of a developing problem, especially in horses with a history of respiratory sensitivity.

❌ Don’t give medication straight away.
- Avoid giving leftover antibiotics or cough syrup without a clear diagnosis. This can mask the symptoms and delay proper treatment.

Your first reaction sets the tone. Quick, calm observation is more helpful than panic or complete inaction.

When to call the vet

Not every cough requires immediate veterinary attention, but some do. It’s better to call the vet early than to wait until it gets worse. Here’s when you should pick up the phone:

🚨 Call your vet immediately if you notice:

A cough at rest, especially if it occurs frequently or gets worse
Fever (above 38.5 °C / 101.3 °F)
Thick yellow or green nasal discharge
Rapid or laboured breathing (distension of the nostrils, visible abdominal effort)
Loss of appetite or lethargy
Refusal to move, or lie down, or signs of general malaise
Blue, grey, or pale gums (signs of poor oxygen supply – urgently needed)

🕐 Contact your vet within a few days if:

The cough persists for more than 3-4 days, even if it is mild
The cough occurs repeatedly (e.g. during training or in the stable)
You recognise a certain pattern, e.g. that the horse only coughs in certain weather conditions or in certain environments
The horse has a history of asthma or allergies, and the symptoms are worsening
You are unsure if the current environment or management is safe

⚠️Don’t wait for the situation to escalate.

Early diagnosis and treatment can make the difference between a simple recovery and a long-term condition. Time counts, especially for horses with sensitive lungs.

The diagnosis: What your vet can recommend

When you call your vet about a coughing horse, it’s about finding the underlying cause, not just treating the symptom. A thorough diagnosis may include the following steps:

🔍 Clinical examination

Listening to the lungs and windpipe with a stethoscope
Observing the breathing rate, breathing rhythm, and breathing effort
Checking temperature, heart rate, and lymph nodes

🔬 Endoscopy (examination of the airways)

A camera is inserted through the nose into the windpipe
Allows visual inspection of mucus, inflammation, or bleeding
Can be used to take samples (tracheal irrigation)

💦 BAL – bronchoalveolar lavage

A small amount of sterile fluid is flushed into the lower airways and collected
It is analysed for the presence of inflammatory cells, bacteria, or allergens
Important for the diagnosis of equine asthma (RAO/IAD)

🧪 Laboratory tests

Tracheal washings or BAL cultures – identify bacterial infections
Blood tests – search for inflammation, infection markers, or immune reactions
Allergy tests (intradermal or serum-based) – optional, but sometimes helpful

💩 Faecal examination (if parasites are suspected)

Check for lungworm larvae
Particularly important for young horses or those that share the pasture with donkeys

An accurate diagnosis helps to initiate effective treatment and avoid the unnecessary use of medication. It also allows for better long-term management – especially if your horse has or is developing a chronic respiratory disease.

Treatment options: What helps and when

Once your vet has determined the probable cause of the cough, treatment can begin. It can be short-term and simple or require a more structured, long-term approach. Here are the possible recommendations:

💊 Anti-inflammatory medication

Corticosteroids (e.g. dexamethasone, prednisolone) – used to reduce airway inflammation, especially in asthma.
NSAIDs (e.g. flunixin) – are used if the inflammation is milder or related to an infection.

Important: Corticosteroids are highly effective but must be used with caution, especially in horses prone to laminitis!

💉 Antibiotics

Are only prescribed if a bacterial infection is confirmed or strongly suspected (e.g. by mucus colour, fever, laboratory results).
Overuse can delay recovery and lead to resistance, so they are not given “just in case”.

🌬️ Inhalation therapy (nebulisation)

Inhalation therapy involves administering medication directly into the lungs using devices such as inhalers or nebulisers.
Often used for corticosteroids, bronchodilators, or saline solution to loosen mucus.
Particularly helpful in chronic cases such as equine asthma.

🌿 Supplements and supportive care

Antioxidants (e.g. vitamin E, selenium) – help to manage oxidative stress.
Herbal support (e.g. mullein, spirulina, MSM) – can help with mucus clearance or inflammation.
Electrolytes – support hydration, especially in hot weather.

Note: Always consult your vet before taking supplements, especially if your horse is taking medication.

Have a read of our article on supplements that support respiratory health.

🧘 Rest and recovery

Horses with infections or acute inflammation benefit from a reduced workload.
Light exercise (e.g. walking) can help loosen the mucus – ask your vet what is appropriate.

🧹 Environmental management (essential in all cases)

Dust reduction: steam or soak hay, improve ventilation, avoid straw bedding
Clean barn: avoid ammonia build-up, remove cobwebs and dust traps
Stable location: as far away as possible from indoor riding arenas or busy stables

Even with medication, poor air quality can further irritate the lungs. Management is half the battle.

Summary

If your horse starts coughing, don’t panic, but don’t ignore it either. Early action can make all the difference, especially if the cough indicates an infection or flare-up of an underlying condition.

In this second part of our series, we have looked at the following topics:

What to look out for in the first few moments
How to decide when to consult your vet
Which diagnostic methods can be used to get to the bottom of the problem
The most common treatment strategies – from medication to environmental changes

Quick action, under the guidance of a vet and with the help of smart management, can often prevent a minor problem from becoming serious or chronic.

👉 Let’s continue: Chronic cough: management and prevention

In the third and final part of our series, we will focus on the following

Preventive strategies to help you stop a cough before it starts
What it means when a cough becomes chronic and what you can do about it
How you can support horses with long-term respiratory conditions
Encouragement and practical tips for long-term management of asthma and allergies

Stay with us – don’t just treat symptoms, strengthen your horse’s respiratory health.