ATC code V04CH30 (WHO) PubChem CID 2148 DrugBank DB00345 | CAS Number 61-78-9 IUPHAR/BPS 4810 | |
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Synonyms PAH, PAHA, Aminohippurate, 4-Aminohippuric acid , N-(4-Aminobenzoyl)glycine, para-Aminohippurate | ||
Aminohippuric acid or para-aminohippuric acid (PAH), a derivative of hippuric acid, is a diagnostic agent useful in medical tests involving the kidney used in the measurement of renal plasma flow. It is an amide derivative of the amino acid glycine and para-aminobenzoic acid that is not naturally found in humans; it needs to be IV infused before use diagnostically.
Contents
Diagnostics
PAH is useful for the measurement of renal plasma flow.
The renal extraction ratio of PAH in a normal individual is approximately 0.92.
Pharmaceuticals
Aminohippuric acid is often used as the sodium salt sodium para-aminohippurate. During World War II, para-aminohippurate was given along with penicillin in order to prolong the time penicillin circulated in the blood. Because both penicillin and para-aminohippurate compete for the same transporter in the kidney, administering para-aminohippurate with penicillin decreased the clearance of penicillin from the body by the kidney, providing better antibacterial therapy. Transporters found in the kidney eliminate organic anions and cations from the blood by moving substances, in this case, drug metabolites, from blood into urine.
Other
In vultures, the NSAID diclofenac, which is extraordinarily toxic to vultures, interferes with the renal transport of uric acid via the PAH channel.
pKa = 3.83