Huperzine A: An Alternative to Prescription Meds for Alzheimer's Disease?

Another question that comes up often regarding Alzheimer's disease (AD) is with regards to treatment & prevention.  Randomized, double blind, placebo controlled studies have demonstrated on more than one occasion that aspirin, conjugated equine estrogens, ginkgo biloba, and vitamin E neither prevent nor treat AD.  That's not to say that you shouldn't take aspirin if you have heart disease or hormone therapy if you suffer from intolerable vasomotor instability.  But be sure you're doing what you're doing for the right reason.

With that said, epidemiological & observational studies have demonstrated a link between activity (both physical & cognitive), fish consumption, and the Mediterranean diet when it comes to lowering AD risk.  Don't get me wrong.  There's no proof of cause & effect here.  But we've been telling our patients all along to make healthier lifestyle choices to minimize their risk for cardiovascular & cerebrovascular disease, so I see no harm in dangling the possibility of AD prevention as another reason to choose wisely.

As for treatment, we have 3 acetylcholinesterase inhibitors (4 if you include one that's very rarely prescribed these days) and 1 NMDA receptor antagonist from which to choose in an attempt to treat AD, essentially closing the barn door after the horses have escaped.  However, as I've mention over & over again, statistically significant improvements on objective cognitive testing doesn't imply clinically significant outcomes.  Moreover, these medications are all very expensive and come with an array of side effects.

Thus, not surprisingly, the next question that arises is for a natural supplement that might prevent or treat AD.  While huperzine A is a natural acetylcholinesterase inhibitor and NMDA receptor antagonist used by the Chinese for thousands of years, is more potent than prescription-only tacrine & galantaimine, has good brain penetration, and is relatively free of cholinergic side effects, it has never been demonstrated in a randomized, double blind, placebo controlled trial to be of benefit in AD.  In fact, a study published in Neurology this month, failed to show any benefit when taken at a dose of 200mcg twice daily by 210 patients w/mild-to-moderate AD for 24 weeks.

However, it's worth noting that some benefit was seen at a dose of 400mcg twice daily.  More importantly, in this Phase II study, there were no short-term safety & tolerability issues noted.  Just beware that nutritional supplements are manufactured & sold without third-party oversight, so you may not be getting the dose you paid for and your product might also be contaminated.  But on the other hand, there does appear to be some benefit to huperzine A at higher dose.

And in case you're following the money, the study was jointly sponsored by the National Institutes of Heallth/National Institute on Aging and Neuro-Hitech, a biopharmeutical company interested in bringing Huperzine A to the market.