Skin cancer is rampant. In an earlier blog, evidence was presented that a common drug for erectile dysfunction, sildenafil (Viagra), had a nasty side effect: Its use was associated with an increased risk of melanoma.
Now, another study from Denmark demonstrates that a popular drug for high blood pressure is dangerous. It substantially raises the risk of non-melanoma skin cancer (NMSC). The NMSC specifically studied was squamous cell carcinoma (SCC), which is easily treated and has a low mortality rate. Nevertheless, it is something we should try to avoid. Hydrochlorothiazide is the drug. It is popular in both the U.S. and Western Europe. Approximately 10% of all cases of squamous cell carcinoma may be caused by Hydrochlorothiazide. Especially relevant is this fact: In Denmark, the risk of developing squamous cell carcinoma is up to seven times greater for users of Hydrochlorothiazide. However, It should be noted that other types of blood-pressure medication did not show the same effects in promoting skin cancer.
Why do we post this information on skin cancer?
The reason for posting this information? To try to halt the idea that sun exposure is the cause of all skin cancers. In fact, there is a plethora of evidence against that idea. Furthermore, regular, non-burning sun exposure is protective against melanoma in most people. In previous blogs for Sunlight Institute, we have offered evidence that lack of foods such as nuts, seeds, tomatoes, greens and fruits increase skin cancer risk. Meat consumption has also been shown to increase the risk of melanoma. So has alcohol consumption. PCB exposure also increases the risk. Being obese is another risk factor. Hence, Hydrochlorothiazide has many partners in promoting skin cancer.
In conclusion: When you see that someone has a skin cancer, think! Is it due to drugs? Is it due to poor nutrition? While sunlight may have an influence on squamous cell carcinoma, we should definitely not immediately determine that it is caused by our friend, the Sun.
 Li WQ, Qureshi AA, Robinson K, Han J. Sildenafil use and increased risk of incident melanoma in US men: a prospective cohort study. JAMA Intern Med. 2014 Jun;174(6):964-70C.
 Arnspang S, Gaist D, Johannesdottir Schmidt SA, Hölmich LR, Friis S,
Pottegård A, Hydrochlorothiazide use and risk of non-melanoma skin cancer: A nationwide case-control
study from Denmark, Journal of American Dermatology (2017), doi: 10.1016/j.jaad.2017.11.04
 Popular blood pressure medicine linked with increased risk of skin cancer. Medical Express News, Nov. 5, 2017. https://medicalxpress.com/news/2017-12-popular-blood-pressure-medicine-linked.html;