Is It Safe To Give My Infant Meftal For High Fever When Fepanil Isn’t Working, And How Long Will The Fever Last?

Hello doctor, for last three days my baby is having high fever (39c) doctor prescribed fepanil 125 3ml.but no cure So I gave him meftal p 3ml Is it safe to use meftal My baby is 8 months old weight 7.7 His fever is coming back and have runny nose as well. I m very worried and don t know what to do Fepanil is not subsiding his fever. Today doctor prescribed one antibiotic as well How long will it take to subside the fever?