For the time being, voice rest, staying hydrated (no caffeinated drinks including tea) and as a prevention -in case it is infectious laryngitis- coconut oil consumption will help, as it is naturally anti-
viral, anti-
bacterial and anti-fungal. 2-5 tablespoons daily, but start with 2T and gradually increase..
Hope this helps, however, my comments and suggestions are not intended as replacement for medical advice.