Comparison of serum levels following the administration of oral and parenteral preparations of penicillin to infants and children of various age groups

Abstract

Summary 1.Penicillin levels in the serum of infants and children of various age groups were obtained following the administration of two oral and two parenteral preparations of penicillin. The various preparations were given in single doses of 10,000 units per pound of body weight. 2.Distinctly higher and more sustained blood levels were observed in the full-term newborn and premature infants than in older infants and children after the administration of comparable doses of all four preparations. The possible explanations for these differences have been discussed. 3.Minor differences have been observed in the levels following the administration of orally administered potassium penicillin-G and orally administered procaine penicillin. 4.Orally administered penicillin in doses of 10,000 units per pound of body weight produced levels of at least 0.03 unit per millititer for a minimum of six hours in full-term newborn and premature infants, for a minimum of four hours in infants up to 2 years of age, and for at least two hours in children over 2 years. 5.In all age groups intramuscularly administered potassium penicillin-G in doses of 10,000 units per pound of body weight resulted in very high initial levels. The levels declined rapidly, however, so that the 6-hour levels were comparable to those observed after the oral administration of penicillin in all age groups except the youngest newborn infants. 6.Intramuscularly administered procaine penicillin in doses of 10,000 units per pound of body weight produced high, sustained levels for six hours; detectable levels were often demonstrable at the end of twentyfour hours. 7.Suggestions have been made for dosage regimens for orally administered penicillin. Summary 1.Penicillin levels in the serum of infants and children of various age groups were obtained following the administration of two oral and two parenteral preparations of penicillin. The various preparations were given in single doses of 10,000 units per pound of body weight. 2.Distinctly higher and more sustained blood levels were observed in the full-term newborn and premature infants than in older infants and children after the administration of comparable doses of all four preparations. The possible explanations for these differences have been discussed. 3.Minor differences have been observed in the levels following the administration of orally administered potassium penicillin-G and orally administered procaine penicillin. 4.Orally administered penicillin in doses of 10,000 units per pound of body weight produced levels of at least 0.03 unit per millititer for a minimum of six hours in full-term newborn and premature infants, for a minimum of four hours in infants up to 2 years of age, and for at least two hours in children over 2 years. 5.In all age groups intramuscularly administered potassium penicillin-G in doses of 10,000 units per pound of body weight resulted in very high initial levels. The levels declined rapidly, however, so that the 6-hour levels were comparable to those observed after the oral administration of penicillin in all age groups except the youngest newborn infants. 6.Intramuscularly administered procaine penicillin in doses of 10,000 units per pound of body weight produced high, sustained levels for six hours; detectable levels were often demonstrable at the end of twentyfour hours. 7.Suggestions have been made for dosage regimens for orally administered penicillin.