Posted by Rick on February 10, 2002, at 5:31:23
In reply to What about Vinpocetine?, posted by Jerrympls on February 6, 2002, at 22:30:57
> Can anyone give me some info on this supplement? Has anyone tried it - experiences? I remember reading about it many years ago and it wasn't available in the U.S. But now I see Nature Made makes it and you can get it at Target. Any info would be greatly appreciated.
This is from the Natural Medicines database, an evidence based library published by the same group of pharmacists who publish respected pharmacutical periodicals such as the Pharmacist's Letter. They are definitely not "rah rah" about herbs and supplements, finding many popular products to be unsafe and unproven. They won't label anything as even "possibly" effective in the absence of well-designed studies, which must include some done on human subjects). Fyi, the references cited are mostly links to Medline-catalogued studies done by medical researchers. Vinpocetine is a precription drug in many, if not most countries.In independent tests, Nature Made tends to be one of the companies that shows greater quality-control. And Vinpocetne is cheap. But from looking at expiration dates of drugstore-shelved Nature Made Vinpocetine, I get the feeling it's not exactly flying off the shelves...at least not in the area I live in.
If cognitive/memory effect is an issue for you, you may also be interested in the Medline abstract I pasted at the bottom, which showed Vinpocetine mildly countering benzo-induced cognitive deficits.
BTW, the half-life of Vinpocetine is only 1 to 2.5 hours, so even if it really is effective I have to wonder if the recommended three-times-a-day dosing would be sufficient.
Rick
VINPOCETINE
Also Known As:
AY-27255, Cavinton, Ethyl Apovincaminate, Ethylapovincaminoate, RGH-4405, TCV-3b.
Scientific Names:
Eburnamenine-14-carboxylic acid, ethyl ester.
People Use This For:
Orally, vinpocetine is used for enhancing memory (1782,1783,1796,1797), improving cerebral blood flow, improving cerebral oxygen and glucose utilization (1782,1783), protecting against age-related cognitive decline and Alzheimer's disease (14,1783,1784), treating cerebrovascular disease (14,1789,1793), preventing post-stroke morbidity and mortality (14,1785), treating organic psychosyndromes (1787), treating intractable tumoral calcinosis in people undergoing hemodialysis (14,1788), decreasing stroke risk (14,1790,1791), treating menopausal symptoms (1792), seizure disorders (1795), and preventing motion sickness (1798).
Intravenously, vinpocetine is injected for treating seizure disorders (1794) and stroke (1786).
Safety:
POSSIBLY SAFE ...when used orally and appropriately (14,1784). No significant adverse effects were reported in a study of people with Alzheimer's disease treated with large doses of vinpocetine (60 mg per day) for one year (1784).
PREGNANCY AND LACTATION: Insufficient reliable information available; avoid using.
Effectiveness:
POSSIBLY EFFECTIVE ...when vinpocetine is used orally for cerebrovascular diseases (14,1787,1789,1793). ...when used orally for enhancing memory (1796,1797).
POSSIBLY INEFFECTIVE ...when used orally for preventing post-stroke morbidity and mortality (14,1785).
There is insufficient reliable information available about the effectiveness of vinpocetine for its other uses.
Mechanism of Action:
Vinpocetine is a synthetic derivative of vincamine, a compound derived from the periwinkle plant, Vinca minor (see separate listing for Periwinkle) (14). Vinpocetine appears to have many varied pharmacologic effects, but mechanisms of action are unclear, and well-designed clinical studies to substantiate activity have not been published (14). A few studies using vinpocetine for poorly-defined cerebrovascular diseases have indicated some efficacy, but faulty study design limits interpretation (14,1787,1789,1793). Vinpocetine had no effect on dementia progression in 15 people with Alzheimer's disease treated for one year with gradually increasing doses up to 60 mg/day (1784). Vinpocetine does not appear to be effective for preventing post-stroke debility or death (14,1785). Some studies indicate that vinpocetine might enhance cerebral blood flow without affecting peripheral blood flow (14,1786,1793). Preliminary evidence indicates that vinpocetine stimulates cerebral metabolism (14). Vinpocetine improves memory in healthy subjects and healthy volunteers with benzodiazepine-induced memory impairment (1796,1797). Potential mechanisms for the nootropic-like effects of vinpocetine include indirect or direct cholinergic activity, augmented norepinephrine effects on cortical cyclic adenosine monophosphate (AMP), increased turnover of brain catecholamines, and inhibition of adenosine reuptake (14,1800). Other pharmacological effects of vinpocetine include increased cerebral glucose utilization, anticonvulsant activity, neuronal protectant activity, adenosine-like effects, and phosphodiesterase inhibition (14). Vinpocetine inhibits drug-induced platelet aggregation (14,1801). The bioavailability of vinpocetine varies from 7% to 57%, and food significantly enhances absorption (14,1802). Vinpocetine undergoes hepatic metabolism to inactive compounds (14). The elimination half-life of vinpocetine is 1-2.5 hours (14). Vinpocetine has been shown not to interact with desipramine, imipramine, glyburide, and oxazepam (14).
Adverse Reactions:
Orally, adverse effects include stomach pressure, upper abdominal pain, nausea, facial flushing, slight reductions in systolic and diastolic blood pressure, sleep disturbances, and headache (14).
Interactions with Herbs & Supplements:
HERBS WITH ANTICOAGULANT/ANTIPLATELET POTENTIAL: Theoretically, concomitant use of herbs that have coumarin constituents or affect platelet aggregation might increase the risk of bleeding in some people. These herbs include angelica, anise, arnica, asafoetida, bogbean, boldo, capsicum, celery, chamomile, clove, danshen, fenugreek, feverfew, garlic, ginger, ginkgo, ginseng Panax, horse chestnut, horseradish, licorice, meadowsweet, prickly ash, onion, papain, passionflower, poplar, quassia, red clover, turmeric, wild carrot, wild lettuce, willow, and others (4,19).
Interactions with Drugs:
ANTI-PLATELET DRUGS: Theoretically, concomitant use with vinpocetine might enhance anti-platelet effects and increase bleeding risk (14,1801).
WARFARIN (Coumadin): Concomitant use with vinpocetine might increase anticoagulant effects and increase bleeding risk; monitor INR (14).
BLOOD PRESSURE LOWERING DRUGS: Theoretically, concomitant use with vinpocetine might enhance blood pressure lowering effects; monitor blood pressure (14).
Interactions with Foods:
FOODS: Administration of oral vinpocetine with food enhances its absorption (1802).
Interactions with Lab Tests:
PROTHROMBIN TIME (PT), INTERNATIONAL NORMALIZATION RATIO (INR): Vinpocetine might increase PT and INR (14). It has been reported to modestly increase warfarin AUC, PT, and factor VII clotting time (14).
BLOOD PRESSURE: Theoretically, vinpocetine might lower blood pressure and blood pressure measurements (14).
BLOOD GLUCOSE: Theoretically, vinpocetine might reduce blood sugar levels and test results (14).
Interactions with Diseases or Conditions:
COAGULOPATHIES: Vinpocetine should not be used by people with blood-clotting disorders because it might increase bleeding risk (14,1801).
Dosage/Administration:
ORAL: The dose commonly used for cerebrovascular disorders is 5-10 mg three times daily (14). People typically take 10 mg three times daily with food (1799).
Comments:
Vinpocetine is a synthetic derivative of apovincamine which is found in periwinkle. Vinpocetine synthesis requires considerable laboratory manipulation, stretching the Dietary Supplement Health and Education Act (DSHEA) definition of a "dietary supplement" (14,1799). Vinpocetine is sold by prescription in Germany under the brand name, Cavinton (9). It has also been referred to generically as cavinton (9). Although website advertising claims that "more than a hundred" safety and effectiveness studies have been funded by the Hungarian manufacturer Gedeon Richter, few double-blind controlled clinical studies have been published (14,1782,1785).
--------Int Clin Psychopharmacol 1987 Oct;2(4):325-31
Vinpocetine effects on cognitive impairments produced by flunitrazepam.
Bhatti JZ, Hindmarch I.
Human Psychopharmacology Research Unit, University of Leeds, U.K.
The effects of pre-treatment with vinpocetine 40 mg, on flunitrazepam-induced impairment of memory, were studied in 8 normal volunteers. Tests of Critical Flicker Fusion Threshold, a Sternberg Memory Scanning Task, along with subjective ratings of drug action were used. Drug effects were found to be modest. Treatment with vinpocetine was associated with improvements in short-term memory processes.
Publication Types:
Clinical Trial
Randomized Controlled TrialPMID: 3693872 [PubMed - indexed for MEDLINE]
poster:Rick
thread:93137
URL: http://www.dr-bob.org/babble/20020208/msgs/93563.html