Viagra May Have Unintended and Positive Side Effects

By: Georgia McKoy | Published: Feb 26, 2024

A study conducted by researchers at University College London (UCL) has discovered a potential link between the use of Viagra, and a reduced risk of developing Alzheimer’s disease.

The research analyzed medical records of 260,000 men with erectile dysfunction and found those prescribed Viagra were 18% less likely to develop Alzheimer’s compared to those not taking the medication. This finding introduces a surprising potential benefit of a drug widely recognized for a completely different purpose.

Greater Reduction in Alzheimer’s Risk with Frequent Use

The study highlighted a more pronounced effect among men who received a higher number of Viagra prescriptions.

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The BBC reports that specifically, individuals who were prescribed the medication 21 to 50 times showed a 44% lower risk of developing Alzheimer’s disease.

Observational Study Highlights Potential Link

While the results of the UCL study are compelling, researchers caution that the observational nature of the study does not confirm causation, The Guardian notes.

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The study cannot definitively prove that Viagra and similar medications protect against Alzheimer’s, nor can it determine if men less prone to the condition are more likely to use these drugs. “We can’t say that the drugs are responsible, but this does give us food for thought on how we move into the future,” stated Dr. Ruth Brauer, the lead author of the study.

Call for Clinical Trials

Given the intriguing findings, the next step according to Dr. Ruth Brauer is to conduct proper clinical trials.

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The Guardian explains that these trials would aim to explore the effects of erectile dysfunction drugs on Alzheimer’s in a controlled setting, thereby providing more definitive evidence. The research team emphasizes the importance of expanding these trials to include women, to understand the drug’s potential benefits across genders.

Viagra’s Unexpected Path

Originally developed for treating angina and high blood pressure, Viagra’s potential effects on brain health have come as an unexpected development.

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The discovery of its “night-time side effects” among Welsh miners led to its widespread use for erectile dysfunction, as per information from The Guardian. Now, the possibility that it could also offer protective effects against Alzheimer’s adds a new chapter to its story.

Mechanism Behind the Protective Effects

The protective effects of Viagra and similar medications, known as PDE5 inhibitors, are thought to be related to their ability to improve blood flow, The Guardian reports.

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This includes potential benefits to brain health, where improved blood flow could help protect against Alzheimer’s disease. Additionally, these drugs are known to increase levels of a compound called cGMP, which may help protect brain cells.

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Need for Further Research

The findings from the study published in the journal Neurology highlight the need for further investigation.

A blister pack containing four blue, diamond-shaped Viagra tablets, with the Pfizer logo visible on each pill

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The Guardian points out that there are various factors, not accounted for in medical records, that could influence the risk of Alzheimer’s, such as levels of physical and sexual activity. This illustrates the complexity of establishing a direct link between Viagra use and reduced Alzheimer’s risk.

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Previous Research Offers Mixed Results

Past studies have shown conflicting results regarding Viagra’s effect on Alzheimer’s risk. For instance, research by the Cleveland Clinic in Ohio found a 69% lower risk of Alzheimer’s among Viagra users, while a study from Harvard found no protective effect.

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These contradictory findings underline the need for more rigorous and targeted research in this area.

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Potential Benefits for Women

According to The Guardian, if further research confirms Viagra’s protective effects against Alzheimer’s, the implications could extend to women as well.

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This possibility opens up new avenues for exploring how PDE5 inhibitors might be used as part of a broader strategy to combat Alzheimer’s disease in both men and women.

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The Advantages of Drug Repurposing

Repurposing existing medications like Viagra for new therapeutic uses offers a promising path for advancing Alzheimer’s prevention strategies.

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Dr. Ivan Koychev, a senior clinical researcher at the University of Oxford, said, “This is a significant development, as repurposing existing drugs for the prevention of dementia is a promising strategy to stop dementia from developing in the first place.”

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Challenges in Clinical Trials

However, conducting blinded placebo-controlled trials with drugs like Viagra poses unique challenges due to their well-known effects, Dr. Koychev notes.

An open pill organizer on a wooden surface, containing several compartments with different medications. Two compartments hold yellow capsules and white oval tablets, respectively, and one contains three blue, diamond-shaped pills with the inscription "Pfizer" on them, typically recognized as Viagra

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Finding a way to conduct these trials without revealing which participants are receiving the active drug will be crucial for ensuring the reliability of the results.

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The Road Ahead

As the research community continues to explore Viagra’s potential role in preventing Alzheimer’s disease, the findings from UCL’s study represent a significant step forward.

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While much work remains to be done, the possibility of repurposing a well-known drug to combat one of the most challenging diseases of our time offers a glimmer of hope.

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