ivermectine for my cockatiel

Question
My cockatiel has been sick and on 3 different antibiotics for 2 weeks now.  She has problems breathing and my vet treats her for chlamydia.  But,  she has lots of mucos, she swipes her beak against any surface all the time, she turns her neck and makes wheezing noices and sneezes and coughs, especially in the night.  I mentioned air sac mite to my vet but she said it is mostly in canaries.  The latest antibiotic she got is doxoral drops (family of tetracycline)0.1 ml once a day.  I gave it this morning at arounc 7:30.  
Having read about air sac mite, and believing that she shows all those signs, and given that she has not responded to the other antibiotics, I would like to try the ivermectine, this one is a "pippet" dosage of 25pg per pipet, to be administered in her neck.  
Before I do this however, can you please advise me if this might be harmful considering that a) she got the other antibiotic this morning, b) she is weak ?
Please, please help I am desperate seeing how she suffers breathing and not getting better...
many thanks... Ileene

Answer
Ileene,

Thank you for bringing your sick bird to an avian vet. Your cockatiel needs to be treated with a tetracycline derivative antibiotic for at least 45 days in order to rid it of the dangerous and highly contagious chlamydia.  You might like to read this article:

http://www.cockatiel.org/articles/psittacosis.html

Your vet appears to know exactly what he or she is doing.  Please do NOT attempt self-treatment for a condition that you cockatiel does not even have.  Your cockatiel is showing classic signs for a chronic case of psittacosis, or chlamydia, and she needs the proper treatment.  Please be sure to clean the perches and cage sides daily and treat the cage to a wipedown and rinse off with bleach every week.

Good luck to you,

Cindy