Hydrochlorothiazide

Consumers and health professionals are advised that the Product Information (PI) and Consumer Medicine Information (CMI) for medicines containing hydrochlorothiazide are being updated to include details about an increased risk of non-melanoma skin cancer.

Hydrochlorothiazide is a diuretic that is used to treat high blood pressure (hypertension), usually in combination with other blood pressure medicines. There is one product that contains only hydrochlorothiazide as an active ingredient (Dithiazide) and many products, including generic brands that include hydrochlorothiazide in combination with other drugs.

Epidemiological studies have found that there is an increased risk of non-melanoma skin cancers associated with medicines containing hydrochlorothiazide. The two most common types of non-melanoma skin cancer are basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Hydrochlorothiazide is known to cause photosensitivity, and it is thought that this is the reason for an increased risk of developing non-melanoma skin cancer.

The findings of studies using population-level data from Denmark have been supported in a recently published study of data from Australian patients undertaken by the University of New South Wales (UNSW).

The Therapeutic Goods Administration is working with sponsors of products that contain hydrochlorothiazide to include a warning about the increased risk of non-melanoma skin cancers, together with advice about avoiding ultraviolet (UV) exposure and getting regular skin checks, in their PI and CMI documents. This will help consumers and their doctors to make informed choices about the benefits and risks of hydrochlorothiazide-containing medicines.

Information for consumers

If you or someone you provide care for takes a medicine that contains hydrochlorothiazide, please be aware of the above information. You should use effective UV protection and get regular skin checks

Non-melanoma skin cancers are the most common cancers in Australia, but most are not life threatening. Further information about non-melanoma skin cancer is available on the Cancer Council website.

BCC is the more common form of non-melanoma skin cancer and often has no symptoms. However, symptoms can include:

• a pearly lump
• a scaly, dry area that is shiny and pale or bright pink in colour.

Symptoms of SCC may include:

• a thickened red, scaly spot
• a rapidly growing lump
• an area that looks like a sore but has not healed
• an area that may be tender to touch.

If you are concerned or have any questions about this issue, speak to your doctor.

Information for health professionals

If you are treating patients with a medicine that contains hydrochlorothiazide, please be aware of the above information and discuss it with those patients.

Educate them on the signs and symptoms of non-melanoma skin cancer and advise them to use effective UV protection and to get regular skin checks.

For further information about this potential adverse event is available in the article regarding the Danish studies and the UNSW press release relating to their recent study.

Reporting problems

Consumers and health professionals are encouraged to report problems with medicines or vaccines. Your report will contribute to the TGA's monitoring of these products.

The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medicine or vaccine.