Hello, Would it be normal for Tetracycline to be used to treat Asthma?

We have a student from Hong Kong living with us who has a huge bag of Tetracycline from Hong Kong. She says she needs it for Asthma and that our cats are causing her to have asthma attacks. All I have found about the drug is that it treats just about anything but Asthma. She does seem to be treating Acne somewhat with some over the counter stuff and her acne was worse when she first arrived here two weeks ago. She has been not eating that much and has complained of tummy pain a little and Asthma or allergy type issues. I think she is trying to get moved to another home because she does not like the rules of the house which involve her calling us to let us know where she is and when we can expect her. She is sixteen who likes to act twenty something. I just want to make sure my assumptions and knowledge of this drug is correct.