Question:
– I got a horse coughing after getting inhalation therapy.

Answer:
There are several theoretical possibilities including:

• If giving corticosteroids in the face of an infection there is a chance of worsening things.
• If bronchodilation &/or improved mucus clearance occurs there may be more expectoration of mucus (could also see increase in nasal discharge temporarily).
• If the horse changes his/her pattern of breathing due to wearing the mask, he/she might cough.
• If there were an adverse response in an individual horse this could cause worsening of clinical signs.
• There could be temporary decrements in ventilation/perfusion relationships following bronchodilation.

Question:
– Using the Equine Haler it has been up served that a couple of the horses have started coughing the first couples of days. Is this normal and if so - Why?

Answer:
It is possible that the propellant is causing some irritation of the airways. I would be concerned if the did not coughing stop after several days, as the steroids (if that is what you are using) should start to de-sensitise the airways.

It could be that if these horses had infection present then treatment with steroids could affect the numbers of bacteria in the airways (i.e. increase them). This is a reason why the diagnosis must be made by tracheal wash with cytology and bacteriology before treating with steroids - which are of course immunosuppresant. In man it used to be thought that you should not treat with inhaled steroids if there was an infection present. Now it is considered that you should increase dose of inhaled medication when an infection is present, but probably also give anti-biotic cover.

Exercise induced asthma

Question:
– We have a horse with Exercise induced asthma. Would you recommend Frusemide for such a horse and which dose? If you use Frusemide would you then treat with steroid at the same time?

Answer:
Although frusemide does have a bronchodilator effect it is not generally used for this purpose. If you want to bronchodilate him I would use clenbuterol initially, this could be combined with inhaled corticosteroids if there is no sign of an infectious process.