Hydrochlorothiazide: Increased risk of non-melanoma skin cancer (basal cell carcinoma, squamous cell carcinoma)

Merck would like to inform healthcare professionals of the increased risk of non-melanoma skin cancer (NMSC) associated with the use of hydrochlorothiazide (HCTZ)-containing medicines. This safety concern was identified from two pharmacoepidemiological studies conducted in Danish nationwide data sources (i.e. Danish Cancer Registry and National Prescription Registry) which reported a cumulative dose-dependent association between HCTZ and NMSC. Healthcare professionals are advised that patients taking HCTZ alone or in combination with other medicines should be informed of the risk of NMSC and advised to check their skin for any new lesions or changes to existing ones. Patients should limit exposure to sunlight and UV rays and to use adequate protection when exposed to sunlight and UV rays.  Suspicious skin lesions should be examined and the use of HCTZ may also need to be carefully reconsidered in patients who have had previous skin cancer. Please refer to the letter for details.
Healthcare professional, Therapeutic Products

Dear Healthcare Professional Letters

12 Dec 2019

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.moh.gov.sg/hpp/, and follow the procedures below to access the MOH Alert system.

Step 1: On the top navigation ribbon of webpage, select 'For Healthcare Professionals' followed by 'Health Professionals Portal' and click on the choice of profession. User will be redirected to the specific HPP webpage for the selected profession.

Step 2: Click on the Restricted Content icon on the left panel of webpage and login via SingPass.

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

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