Hey there! My vet has me nebulizing some meds before runs but I would like to use something once in a while for maintenance. I was told Eucalyptus and peppermint were best. Both my horses have allergies. Few people told me to make a mix of 250cc saline and 1.5cc eucalyptus/peppermint oil. Every one I have read up on says external use only or in a humidifier. Nothing mentions its ok in a nebulizer. What do you think??? Thanks! 

I don't know about this for horses, but I do know that inhalation of things like petroleum jelly and oils are not a good thing in humans.  It has garnered some attention because of oils getting in lungs in people who vape.  It has happened in horses who have aspirated mineral oil when being treated for things like impaction colic.  Seems like a small amount, but if it were me I wouldn't do it.  

I'm not a believer in the Hocus pocus EO stuff but they are not petroleum based. 

I don't know if that matters and I don't know if you lose the magic with out petro but 

Thanks all! I have decided I am going to stick with saline and the meds my vet prescribed. 

Ask your vet about colloidal silver.  I use it I’m my nebulizer

NO  no no   I worked at a therapy barn and the lady that makes the original machine says no way! collidal silver and what the vet prescribles.  you dont mess with lungs!  If you get time call the lady and she will share her knowledge with you! and what you can and cant do with these machines.  I'm sorry I cant remember her name but can see her face! but she is on fb and if you go to Summer Terry page for therapy you can find her there too.