Daughter Still Sick - Die Off? (antibiotics?)/nausea

My daughter has been on supps/vits/probiotics for about 5 weeks now and "pretty much" following the diet - she's 17, been dealing w/sickness for 5 years. Anyway, about 4 weeks ago she got the worst flu she's ever had. Sore throat, nausea/vomiting, coughing, mucus and some white stuff coming out of her BM's. It did calm down, but the cough (bad) remains and her nausea is still coming and going - that's what first started 5 years ago. Could this lingering on be die-off - she doesn't have anything really in her BM's anymore, but still doesn't feel great off and on. Her pediatrician said she might have a sinus infection, has a lot of drainage in her throat, but I don't want to put her on anti-biotics - what else can she use to clear up an infection?

Ok, I guess my questions are:
1) is this all still die-off
2) do any of you get intermittent nausea/vomiting (we can't pinpoint to certain foods)
3) What do we in place of antibiotics and how long can we expect her to be sick if this is die-off

Help please - she graduates next month and needs to be well for that! This is horrible...Thanks. TJ

If anyone out there had a child suffering w/similar symptoms I'd love to e-mail w/you as a support network...

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