my child has strp throat infection from last 4 to 5 months. he is 17 years old.his swab test for c/s is done.STREPTOCOCCI GROWN ON CULTURE is found.he is sensitive for -Ampicillin/Sulbactam -Nitrofurantoin -Cefpodoxime -Imipenem -Lomefloxacin after seeing his report Dr suggested CEFTUM 500 MG FOR FIVE DAYS .but he has no relif .plz suggest proper medicine for him .he is in 12 th and preparing for IIT. Already he has taken so many antibiotics.