Can rash come and go within an hour? Better with antihistamines?

Im positive for Lyme and one of my main symptoms for about 3 years has been hives that come and go, mostly my arms and torso. Ive been on Doxycycline for about 3 weeks now and have been getting a new kind of rash around my cheeks and nose area, and now my scalp. I thought it might be sun related but its also happening after taing medication in the middle of the night so..

Wondering if a Lupus rash can come and go within an hour or so, or if antihistamines would actually help it diminish?

Thanks for any help.