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One Little-Known Side Effect of Taking Viagra

This little blue pill has surprising side effects.
FACT CHECKED BY Emilia Paluszek

Viagra (sildenafil citrate) is known for treating erectile dysfunction—but doctors say it can have some very unexpected side effects. "Here's a drug that not only treats angina and is good for the heart, but it works on the penis when other medications don't," says urologist Drogo Montague, MD. Here are five side effects of taking Viagra, according to experts. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.

1

Viagra and Heart Health

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Researchers have discovered that Viagra can help protect the heart from chemically induced stress. "Sildenafil effectively puts a 'brake' on chemical stimulation of the heart," says cardiologist David Kass, MD, professor at The Johns Hopkins University School of Medicine. "Knowing more about the effects of sildenafil on heart function will allow for safer evaluation of its use as a treatment for heart problems. Until now, it was widely thought that drugs like sildenafil had no effects on the human heart and that its only purpose was vasodilation in the penis and the lungs. Our results set the stage for further studies of sildenafil's immediate and long-term effects on the heart and its ability to modify other neurohormonal and stress stimuli, including adrenaline and hypertension."

2

Viagra and Lung Health

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Viagra has been shown to be effective in relaxing lung vessels, which lowers blood pressure in the lungs. The drug may also help people with idiopathic pulmonary fibrosis, where scarring in the lungs could result in a lung transplant. "Over five million worldwide suffer from this devastating disease, so we are hopeful that this drug may prove an effective therapy for pulmonary fibrosis," David A. Zisman, MD, medical director of UCLA's Interstitial Lung Disease Program and assistant professor of pulmonary and critical care medicine at the David Geffen School of Medicine at UCLA.

3

Viagra and Colorectal Cancer

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Animal studies have shown that a small daily dose of Viagra could help prevent colorectal cancer, according to scientists. "Giving a baby dose of Viagra can reduce the amount of tumors in these animals by half," says Darren D. Browning, PhD, cancer researcher at the Georgia Cancer Center and Department of Biochemistry and Molecular Biology at the Medical College of Georgia at Augusta University. "When we give Viagra, we shrink the whole proliferating compartment. Proliferating cells are more subject to mutations that cause cancer."

4

Viagra and Obesity

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Viagra has been shown to help treat obesity, researchers say, by encouraging our bodies to store "good" brown fat rather than "bad" white fat. "There is a growing need for novel treatments against obesity," says Alexander Pfeifer, MD, PhD, from the Institute of Pharmacology and Toxicology at the University of Bonn, Biomedical Center in Bonn, Germany. "Finding new positive effects of existing drugs, such as sildenafil, in adipose tissue might help to bridge the period until novel drugs against obesity have been developed."

5

Viagra and Alzheimer's Disease

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A growing body of research shows that Viagra could be a highly effective treatment for Alzheimer's disease. "Notably, we found that sildenafil use reduced the likelihood of Alzheimer's in individuals with coronary artery disease, hypertension and type 2 diabetes, all of which are comorbidities significantly associated with risk of the disease, as well as in those without," says Feixiong Cheng, PhD, of Cleveland Clinic's Genomic Medicine Institute. "Because our findings only establish an association between sildenafil use and reduced incidence of Alzheimer's disease, we are now planning a mechanistic trial and a phase II randomized clinical trial to test causality and confirm sildenafil's clinical benefits for Alzheimer's patients. We also foresee our approach being applied to other neurodegenerative diseases, including Parkinson's disease and amyotrophic lateral sclerosis, to accelerate the drug discovery process."

Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more
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