however, since it is just as easy to use larger doses of penicillin as to administer a second drug for the purpose of preventing its excretion. Probenecid, on the other hand, has an important clinical application as a uricosuric drug. A number of repository preparations of penicillin are available for the purpose of producing sustained blood levels. Procaine penicillin g and benzathine penicillin g are two such preparations. With the latter preparation, demonstra ble penicillin blood levels can be maintained for as long as 20 days. It is important to keep in mind, however, that demonstrable blood levels are often defined as 0. 03 unit/ml or more. This low concentration of the antibiotic may not suffice in many infections, although it may be beneficial in prev ention of streptococcal infections and prophylaxis of rheumatic fever. [ru: maetik] (prevention) Distribution of penicillin in the body is far from uniform First, the antibiotic is partially bound to plasma proteins. Under normal circumstances it penetrates poorly into the cerebrospinal fluid, aqueous humor, and joint fluids On the other hand, inflammation at these various sites greatly increases the permeability to penicillin. [seribrau'spa inal [pa: mia bilitihowever , since it is just as easy to use larger doses of penicillin as to administer a second drug for the purpose of preventing its excretion. Probenecid, on the other hand, has an important clinical application as a uricosuric drug. A number of repository preparations of penicillin are available for the purpose of producing sustained blood levels. Procaine penicillin G and benzathine penicillin G are two such preparations. With the latter preparation, demonstrable penicillin blood levels can be maintained for as long as 20 days. It is important to keep in mind, however, that demonstrable blood levels are often defined as 0.03 unit/ml or more. This low concentration of the antibiotic may not suffice in many infections, although it may be beneficial in prevention of streptococcal infections and prophylaxis of rheumatic fever. [ ]（prevention） Distribution of penicillin in the body is far from uniform. First, the antibiotic is partially bound to plasma proteins. Under normal circumstances it penetrates poorly into the cerebrospinal fluid, aqueous humor, and joint fluids. On the other hand, inflammation at these various sites greatly increases the permeability to penicillin. [ ] [ ]