A study of health insurance data for more than 7.2 million people showed a nearly 70% lower risk of developing Alzheimer’s in the next six years among those who took sildenafil (Viagra) versus those who did not. Viagra was originally designed as a heart drug because of its main action of improving blood flow by relaxing or widening blood vessels. Doctors then discovered it was having a similar effect elsewhere in the body, including the arteries of the penis, and it was developed into a successful treatment for erectile dysfunction. It is also been used in the treatment of pulmonary hypertension. Experts think it could have other uses too. It is important to note that observed associations like this, even on a huge scale, are not the same as proof of a causative effect. Researchers state the correlation shown as well as other indicators in the study are enough to identify sildenafil as a promising candidate drug for Alzheimer’s disease.
