Comparative Pharmacology
Head-to-head clinical analysis: AZATHIOPRINE SODIUM versus IMURAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AZATHIOPRINE SODIUM versus IMURAN.
AZATHIOPRINE SODIUM vs IMURAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Azathioprine is a prodrug of 6-mercaptopurine. It inhibits purine synthesis by interfering with the synthesis of DNA, RNA, and cellular proteins, thereby suppressing immune responses.
Imuran (azathioprine) is a purine antimetabolite that inhibits DNA synthesis by interfering with purine metabolism. It is converted in vivo to 6-mercaptopurine (6-MP), which is further metabolized to thioinosinic acid and thioguanine nucleotides. These metabolites inhibit de novo purine synthesis and incorporation of purines into nucleic acids, thereby suppressing T-cell proliferation and antibody production.
1-2 mg/kg/day IV or oral, initially; maintenance 0.5-1 mg/kg/day IV or oral. For severe organ rejection: 3-5 mg/kg/day IV.
Initially 3-5 mg/kg/day orally once daily; maintenance dose 1-3 mg/kg/day orally once daily. IV dose equivalent to oral.
None Documented
None Documented
Terminal elimination half-life of azathioprine is approximately 3-5 hours; its active metabolite 6-mercaptopurine has a half-life of 0.5-1.5 hours. However, the pharmacodynamic effect (immunosuppression) persists longer due to intracellular accumulation of thioguanine nucleotides.
Azathioprine: 0.16–0.75 h; 6-mercaptopurine: 1.5–4.7 h (terminal). Extended up to 5 h in renal impairment. Context: short half-life allows daily dosing; clinical effect persists due to active metabolites.
Primarily renal: approximately 50% as unchanged drug and metabolites (6-mercaptopurine, thiouric acid) within 24 hours. Biliary/fecal excretion accounts for minor fraction (<5%).
Primarily renal excretion of inactive metabolites; 50% as 6-thiouric acid and other metabolites; <2% unchanged. Minor biliary/fecal elimination (<10% total).
Category D/X
Category C
Immunosuppressant
Immunosuppressant