Stomach flu back ache

Though many people suffer from gastric infections or the stomach flu caused by bacterial or viral infections a backache is not a common symptom of such stomach flu. In rare cases where there is general weakness and lack of bone strength, the patients may experience some backache. In cases of certain bacterial infections, due to dehydration the whole body becomes weak; at such times, the patient might experience backaches, but this is not directly related to the flu, but is more a result of the resultant weakness. Plenty of fluids and to make up for the loss of energy through diarrhea or vomiting should prevent weakness and backaches.

Hey Avantika,
Lindsay is right. Stomach flu is causes mainly by viral or bacterial infection. Back ache is not related any way to your stomach flu. it may be due to weakness of body or the bad posture. Even long time of bed rest can lead to back ache.