High anti-streptococcal hemolysin O is caused by streptococcal infection, and elevated anti-O indicates the presence of streptococcal infection. For elevated anti-O level, if the patient has no symptoms of upper respiratory tract infection and there is no swelling and pain in the joints, no special treatment can be done for patients with mild anti-O elevation. The most classic clinical treatment for streptococcal infection is the long-acting penicillin benzathine penicillin.