Comparative Pharmacology
Head-to-head clinical analysis: P A S SODIUM versus PASER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: P A S SODIUM versus PASER.
P.A.S. SODIUM vs PASER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
P.A.S. (p-aminosalicylic acid) sodium is a bacteriostatic agent that competitively inhibits the synthesis of folic acid in Mycobacterium tuberculosis by antagonizing the incorporation of p-aminobenzoic acid (PABA) into dihydrofolate. It is selective for mycobacterial folate synthase.
Inhibits cell wall synthesis in Mycobacterium tuberculosis by blocking mycolic acid synthesis. Also acts as a competitive inhibitor of folate synthesis.
Oral: 4 g three times daily (total daily dose 12 g); IV: 12 g daily in 2-4 divided doses.
4 g (8 capsules of 500 mg) orally every 8 hours, taken with food or an acidic beverage (e.g., orange juice) to enhance absorption.
None Documented
None Documented
1 hour (normal renal function); prolonged to 5-7 hours in anuria or severe renal impairment; clinical context: requires frequent dosing or renal dose adjustment
Terminal elimination half-life is 1.5 to 2.5 hours in patients with normal renal function. In anuria or severe renal impairment (CrCl <10 mL/min), half-life may extend to 8-12 hours. Clinical context: Accumulation occurs with renal failure, requiring dose adjustment.
Renal (80% as active drug and metabolites, primarily acetylated form); fecal (minor; <10%)
Renal excretion accounts for approximately 80% of the administered dose, with about 60-70% as unchanged drug and 10-20% as metabolites (primarily acetylated). The remainder is excreted via feces (approximately 10-15%) and minor biliary elimination. Renal clearance is highly dependent on glomerular filtration rate.
Category C
Category C
Antitubercular Agent
Antitubercular Agent