Welcome to HCM,this is really unfortunate that she has developed before such an important event,but if she has body ache
, Malaise, most important scratchy throat.
She should do hot saline gargles every 2 hours to clear throat and for other complaints she can take a Paracetamol
tab which should help her to get relief.
A good antiseptic and anti inflammatory gargles will help a lot like Chlorhexidine
and even diclofenac
.Even a hot soup, a hot coffee should help her.I wish her best of luck for her audition, and speedy recovery.
Please take care
Best of luck once again.