Can I Give My Child Mucolite Syrup For Continuous Coughing With Mucus?

My 5 year old boy contiously coughing every 5 minute s...he can t spit up mucus.... doctor recommended to give ambrxil expect it s not at all reduce the cough...but he is active taking food ....no fever....only coughing...can I give him mucolite syrup....kindly help me sir....I got chest pain whenever I heart his coughing sound...pls kindly help