Product Information

Registration Status: Active

IMURAN TABLET 50mg is approved to be sold in Singapore with effective from 1988-06-24. It is marketed by DCH AURIGA SINGAPORE, with the registration number of SIN02082P.

This product contains Azathioprine 50mg in the form of TABLET, FILM-COATED. It is approved for ORAL use.

This product is manufactured by Excella GmbH in GERMANY.

It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.



An immunosuppressive antimetabolite pro-drug. It is an imidazolyl derivative of 6-mercaptopurine and many of its biological effects are similar to those of the parent compound. Azathioprine is converted into 6-mercaptopurine in the body where it blocks purine metabolism and DNA synthesis.


For use in rheumatoid arthritis, preventing renal transplant rejection, Crohn's disease, and colitis.

Mechanism of Action

Azathioprine antagonizes purine metabolism and may inhibit synthesis of DNA, RNA, and proteins. It may also interfere with cellular metabolism and inhibit mitosis. Its mechanism of action is likely due to incorporation of thiopurine analogues into the DNA structure, causing chain termination and cytotoxicity.


Well absorbed following oral administration.
Primarily converted to the active metabolites 6-mercaptopurine and 6-thioinosinic acid via a non-enzymatica process and glutathione transferases. Activation of 6-mercaptopurine occurs via hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and a series of multi-enzymatic processes involving kinases to form 6-thioguanine nucleotides (6-TGNs) as major metabolites


The oral LD50 for single doses of azathioprine in mice and rats are 2500 mg/kg and 400 mg/kg, respectively. Very large doses of this antimetabolite may lead to marrow hypoplasia, bleeding, infection, and death.

Active Ingredient/Synonyms

6-((1-Methyl-4-nitro-1H-imidazol-5-yl)thio)-1H-purine | 6-(1'-Methyl-4'-nitro-5'-imidazolyl)-mercaptopurine | Imuran (tn) | Azathioprine |

Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.


  1. Health Science Authority of Singapore - Reclassified POM
  2. Drugbank