Suggest Treatment For Hives After Having Minocycline

Question: My daughter age 21 took a total of capsules of Minocycline 100 mg one on Dec 23rd and the 2nd one on Dec 30. The main symptom we noticed was extreme itching which we realized were hives. We believe it started within days of taking it. So we went back to the dermatologist today and she gave us an antihistamine Hydroxyzine HCL 25 mg to take at bedtime for a month to flush it out of the system. The itching had gotten worse yesterday (sunday to monday) and the dermatologist mentioned hives present themselves within 2 weeks of taking the Minocycline. It seems like my daughter has a reaction to that antibiotic. It may be she's allergic to Tetracycline? Anyways earlier today she started complaining of stomache. We thought that maybe she ate something that didn't agree with her. Then she had nausea and started with the chills. She took an alkaselzter and I took her temperature and had 100.1 She had diarrhea and once she vomited, she felt better a little better. The pharmacist told me that nausea, fever, chills and general ill feelings were also possible more serious side effects of the Minocycline. The itching so far is better but I'm concerned about these other symptoms if they are related to antibiotic or not? Is this something that just gets worse and should I take my daughter to the ER?
She only took 2 capsules in total of the antibiotic Minocycline 100 mg.