• Huperzine A is a magnificent, yet largely unrecognized supplement useful in the treatment of a variety of conditions that involve blood flow regulation.  A 'natural' phosphodiesterase inhibitor (PDE),  Huperzine enhances blood flow to a variety of tissues, organs and systems, making it useful in the support of: Alzheimer's Disease, erectile dysfunction, kidney disease, peripheral vascular and ocular disease states.
• Zhong, MQ et al: Huperzine A: Is it an Effective Disease-Modifying Drug for Alzheimer's Disease.  Please follow this link for an article on the subject, published in 2014.  

The vasodilatory effect is rapid and can sometimes be remarkable.  I prefer my patients to start off by taking 1 tablet in the morning and again in the evening.  After a week or so, increase to 1 tablet three times daily, and again wait a week.  Increase to 4 per day, if tolerated.   Some persons are more sensitive than others, and headache can occur if the ramp up is too rapid.