Nitrosamine impurity 1-methyl-4-nitrosopiperazine (MNP) found in rifampicin products

The Health Sciences Authority (HSA) would like to inform healthcare professionals about the recent findings of a newly discovered nitrosamine impurity, 1-methyl-4-nitrosopiperazine (MNP), in rifampicin products. HSA has tested and found that all the rifampicin products in the Singapore market contain trace amounts of MNP. However, in consultation with local infectious diseases experts, HSA has assessed that the benefit of rifampicin, being an essential medicine for active and latent tuberculosis and its role in curtailing the spread of tuberculosis, far outweighs the theoretical long-term risk posed by MNP. In consideration of this, HSA will temporarily allow the supply of rifampicin products with trace amounts of MNP so that patients can have continued access to this essential medicine. Please refer to the letter for details.
Healthcare professional, Industry member, Therapeutic Products
Published:

Dear Healthcare Professional Letters

23 Apr 2021

Only abstracts of the Dear Healthcare Professional Letters (DHCPL) are provided on this website. Details of the letters can be found on the MOH Alert System, which is accessible via the Health Professionals Portal (HPP). HPP is a one-stop portal for all healthcare professionals in Singapore. Dentists, medical doctors and pharmacists may access HPP at https://www.hpp.moh.gov.sg/, and follow the procedures below to access the MOH Alert system.

Step 1: Scroll down to the bottom navigation panel of the HPP web page. Under the Healthcare Professionals section, expand the dropdown option for ‘Healthcare Professional Portal’ and select your profession. You will be redirected to the specific HPP web page to log in.

Step 2: Click on the Restricted Content icon on the left panel of the web page and log in via SingPass.

Step 3: Click on the MOH Alert icon under the ‘Applications’ section.

Step 4: Click on the Drug Alert tab to view the DHCPLs.