What causes asthma attacks at night?

My daughter is 8 years old. Within the last week she has woken up with asthma attacks during her sleep. Everything is the same in her room as it always has been. Sleeping on the couch hasn't helped. She has nightmares which in turn made me wonder if maybe she was having nocturnal panic attacks, but it's more of I can't catch my breath, pale face with lips turning blue reaction. She says that she hasn't been having nightmares when they occur. We recently acquired a kitten, which was my first guess of being the problem. She's always had the sniffles but I've realized it's been worse as well. I took her to the doctor and talked about the situations and was given Claritan for allergies. Leaving me to think it was allergies alone causing the issue and still baffled because the medicine doesn't help. She has Bronchial Asthma to begin with but it's usually only worsened by sickness and only ever bothersome then as well. I'm confused, tired from lack of sleep, and really frustrated! The holiday weekend isn't making finding the solution any easier as well.