What does the $4 billion a year, blockbuster Alzheimer's drug donepezil (trade name Aricept) have in common with insecticides, chemical weapons and venom? Quite a lot more than consumers taking them have been lead to believe.
As a member of the chemical class known as acetylcholinesterase inhibitors, donepezil interferes with the cholinesterase enzyme, preventing the neurotransmitter acetylcholine from breaking down, resulting in an increase in both its levels and duration of action.
While this can result in a temporary increase in memory, there is currently no definitive proof that use of donepezil or other similar agents slows the progression of Alzheimer's disease. Moreover, 21% of patients on this medication discontinue its use within 12 months due to serious adverse side effects.
Donepezil is considered a reversible or non-competitive cholinesterase inhibitor, and therefore will not be as toxic as the reversible competitive or noncompetitive inhibitors of cholinesterase which kill insects and humans through its neurotoxic effects. The problem, however, is that -- as is the case with virtually all FDA-approved, novel and patented chemical drugs -- it is evolutionarily and biologically unprecedented, representing a classical case of repackaging one of a drug's many "side effects" as a "therapeutic action." After all, Alzheimer's disease, or any neurodegenerative condition, is not caused by a lack of any drug. In other words, the very premise upon which Alzheimer's is treated with donepezil is bankrupt at the outset.
In 2010, the World Health Organization published a report which looked at over 71,000 documented cases of drug-induced seizures between 1998 and 2006 and found that donepezil was a major contributing factor in 8.4% of them.
Seizures represent the tip of a massive iceberg of adverse effects. Another classical side effect of organophosphate insecticide poisoning is bradycardia (arrhythmia), a well documented side effect of donepezil.
What is so outrageous about the present situation is that non-patentable, inexpensive and relatively safe alternatives to intrinsically neurotoxic drugs like donepezil not only exist, but have been confirmed through clinical research. Take gingko biloba for example. In 2006, the European Journal of Neurology published the results of a 24-week randomized, placebo-controlled, double-blind study showing an extract of this plant was as effective as donepezil for mild-to-moderate Alzheimer's disease:
Our study suggests that there is no evidence of relevant differences in the efficacy of EGb 761 [gingko biloba] and donepezil in the treatment of mild-to-moderate Alzheimer's dementia, so the use of both substances can be justified. In addition, this study contributes to establish the efficacy and tolerability of the Ginkgo biloba special extract E.S. in the dementia of the Alzheimer type with special respect to moderately severe stages. Source
Gingko biloba also has over 100 other potential medicinal applications . The reality is that there is a vast array of natural approaches available in the prevention and treatment of Alzheimer's disease, some of which have been demonstrated to regress the disease process by clearing pathological beta-amyloid brain plaque (Abeta).
A 2006 study in the Journal of Alzheimer's disease reported on this phenomena with the use of curcuminoids (an extract of Turmeric):
The natural product curcuminoids enhanced brain clearance of Abeta in animal models. We, therefore, treated macrophages of six AD patients and three controls by curcuminoids in vitro and measured Abeta uptake using fluorescence and confocal microscopy. At baseline, the intensity of Abeta uptake by AD macrophages was significantly lower in comparison to control macrophages and involved surface binding but no intracellular uptake. After treatment of macrophages with curcuminoids, Abeta uptake by macrophages of three of the six AD patients was significantly (P<0.001 to 0.081) increased. Source
When combined with vitamin D, the effect is enhanced, as described in a 2009 study in the same journal. These findings are not novel, as there are at least 30 other studies indicating the anti-Alzheimer's properties of curcuminoids.*
Unfortunately, natural substances will never receive FDA approval because no one will invest the billion dollars or more in capital (or risk the opportunity costs should it fail) necessary to pay for drug development and clinical trial phases 1, 2 and 3 on a substance that can be grown in your backyard for free. It therefore becomes necessary to alter the structure/function of natural compounds ostensibly to "improve upon nature," while actually doing nothing more than granting the manufacturer patent exclusivity and a potentially astronomical return on its investment. Of course, the unintended adverse effects of such a manipulation are devastating, resulting in the loss of hundreds of thousands of lives from drug-induced toxicity every year.
We should remember that while Nature's formulas are proprietary -- i.e. refractory to the pharmacological gaze -- she does not grant patents. In other words, they are gifts -- as health too is our birthright.