Need more details to give advice for you. First of all Child's age and weight are needed to prescribe any medication and here your child is having high grade fever which needs evaluation for that you need to provide few more details like since howmany days these fever episodes started, any other complaints etc. Take online consultation for further advice. Don't neglect as it is high grade fever.
Next Steps
For now maintain temperature chart, give paracetamol every 6th hourly(after food) if fever is not controlled. paracetamol dose depends on his weight.
Health Tips
High grade fever in pediatric age group is very risky, if not controlled can lead to seizures rarely. Take pediatrician consultation, get treated and let your child stay healthy.