Child's age: 2 - 3 months How much 1. Post-vaccination fever 2.5 ml. If necessary, after 4-6 hours, give a second 2.5ml dose 2. Other causes of pain and fever - if your baby weighs over 4 kg and was born after 37 weeks 2.5 ml. If necessary, after 4-6 hours, give a seco...