It inhibits a number of enzymes responsible for metabolizing drugs and nutritional substances; it stimulates the activity of amino-acid transporters in the intestinal lining; it inhibits p-glycoprotein, the pump protein that removes substances from cells; and it decreases the intestinal production of glucuronic acid, thereby permitting more of the substances to enter the body in active form. Consequently, some of these substances are able to reach, enter, and remain within their target cells for longer periods of time than would otherwise be the case. Of course, this can be a mixed blessing if one is using a drug for which the therapeutic level is not substantially lower than the toxic level, piperine supplementation might raise the bioavailability of the drug until its intracellular concentration exceeds the toxic threshold. On the other hand, piperine supplementation can sometimes turn a marginally effective therapeutic substance into a highly effective one simply by increasing its bioavailability and intracellular residency time.
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Piperine may reduce bioavailability of some substances
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Dosage
The usual recommended dose of piperine is 5-15 mg/day. It is absorbed quickly and well from the digestive tract. Effects on absorption of other substances begin around 15 minutes after dosing and last for an hour or two. Blood levels peak about 1-2 hours after dosing but effects on metabolic enzymes can last much longer from one to many hours, depending upon the enzyme type.
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The most reliable method for ensuring piperines effectiveness is to take a piperine dose about half an hour before taking the substance whose bioavailability one wants to enhance.
Theoretically, using piperine on a daily basis can put the body in a continuous state of altered metabolism for certain substances.
delano.com
Leantodo el artículo. precaución, sobre todo si toman medicamentos.
La piperina se consigue a bajo precio en beyond-a-century.com
Nootrópicos (smartdrugs, drogas inteligentes, potenciadores cognitivos) son sustancias artificiales (medicamentos como piracetam, hydergina, citicolina, fosfatidilserina, vinpocetina, etc.) o naturales (suplementos nutricionales, vitaminas, aminoácidos, hormonas, hierbas, etc. como vitaminas B, piroglutamato, Gingko Biloba, fenilalanina, DHEA, pregnenolona, etc.) que se utilizan para mejorar la capacidad cognitiva (memoria, atención, etc.) en personas con trastornos o normales.