Dosage and Duration Therapy of Amoxicillin

Dosage and Duration Therapy of Amoxicillin
The duration of amoxicillin therapy depends on the type and severity of infection and should be determined by the clinical and bacteriologic response of the patient. For most infections, except gonorrhea, therapy should be continued for at least 48-72 hours after the patient becomes asymptomatic or evidence of eradication of the infection has been obtained. Persistent infections may require several weeks of therapy. Amoxicillin usually is continued for 60 days for postexposure prophylaxis or treatment of inhalational or cutaneous anthrax in the context of biologic warfare or bioterrorism.

If amoxicillin is used in the treatment of infections caused by group A -hemolytic streptococci, therapy should be continued for at least 10 days to decrease the risk of rheumatic fever and glomerulonephritis.

If amoxicillin is used in the treatment of chronic urinary tract infections, frequent bacteriologic and clinical appraisal is necessary during therapy and may be required for several months after therapy.

In patients with renal impairment, doses and/or frequency of administration of amoxicillin should be modified in response to the degree of renal impairment, severity of the infection, and susceptibility of the causative organisms. The manufacturer states that adults with severe renal impairment and creatinine clearances less than 30 mL/minute should not receive the commercially available film-coated tablets containing 875 mg of amoxicillin. The recommended dosage of amoxicillin for adults with creatinine clearances of 10-30 mL/minute is 250 or 500 mg every 12 hours, depending on the severity of the infection, and the recommended dosage for adults with creatinine clearances less than 10 mL/minute is 250 or 500 mg every 24 hours, depending on the severity of the infection.

Patients undergoing hemodialysis should receive 250 or 500 mg of amoxicillin every 24 hours, depending on the severity of the infection, and should receive an additional dose of the drug during and after each dialysis period.

The manufacturer states that data are insufficient to recommend dosage for pediatric patients with renal impairment.