HI, at times it depends on the intensity of infection as judged by your doctors, and maybe clinical and therapeutic recommendations might suggest an increase in the dosage, more than what s on the leaflet, but bits worthwhile checkikng again with your family physician. t s a usual side effect of the drug, and you could see your doctor and stop the drug if side effects really becoming persistent and preoccupying. Do nnot actually think theheart murmur is due to the drug, remember, if your nduaghter has been having recurrent poorly treated tonsillitis, its not unusual for the heart valves to be juged, reason why the doctors insist on an effective treatment to eradicate the germ, Group A streptococci. I suggest you meet the doctor for a keen and strict follow up mof your daughter. Poor treatment of this condition could predispose the child to having heart disease (valvular disease), joint disease in future or Rheumatic fever.