OK, I am speaking as a paramedic now. Please read carefully. The fact that your child’s voice has changed and that it is difficult for him to speak could mean there is swelling that may close off his airway. This could be a life-threatening condition, and it could happen in the next few moments or the next few hours. Unless you are limited by financial means, this would be an entirely justified reason for calling the ambulance. Especially if your area is serviced by advanced life support paramedics. They may be in a position to intervene to delay or prevent the swelling in the throat from closing off your child’s airway. If you live in Canada, the United States, England, Australia or anywhere there is a good ambulance service, please call them now. Do not drive your child to the hospital yourself unless you are 10 minutes away or less.