Pituitary hormones trigger the synthesis of pregnenolone from dietary cholesterol. This steroid hormone serves as a building block for progesterone, estrogen and testosterone. Aging can decrease circulating levels of pregnenolone, creating a deficiency syndrome. Hormonal deficiencies may increase the risk of disease and injury. Taking synthetic pregnenolone reverses these unwanted changes, but it also causes side effects. Speak with a healthcare professional before initiating hormone replacement therapy.
Improves Memory
The aging population creates a large group of people at risk for dementia. Prevention of negative age-related changes in cognitive performance reduces the economic burden of this debilitating disorder. A 1992 study in the "Proceedings of the National Academy of Sciences" looked at the ability of pregnenolone to enhance memory in laboratory animals. Rodents received either the supplement or an inert treatment immediately following a memory task. Mice given pregnenolone showed greater retention than those given dimethyl sulfoxide that had no effect. Tests in humans may not reveal the memory-enhancing properties of pregnenolone shown in animals.
Treats Schizophrenia
Pregnenolone may prove useful in treating existing disorders as well. Psychotropic medications such as haloperidol help people with schizophrenia manage hallucinations and delusions. Yet, these drugs often cause negative reactions. A 2009 report in "Neuropsychopharmacology" tested the effectiveness of pregnenolone in reducing medication-induced body movements. Eighteen schizophrenics received either the supplement or a placebo for eight weeks. Patients given pregnenolone showed improvement in daily functioning relative to those given no treatment. They also showed increases in cognitive performance. The treatment was well tolerated. These results need to be confirmed in experiments testing a larger number of subjects.
Reduces Performance
The benefits of pregnenolone may come at a price as the supplement often produces unwanted effects. A 2004 article in the journal "Psychopharmacology" evaluated the hormone's impact on a learning task in laboratory rodents. Rats received either pregnenolone supplements, prescription medications or an inert treatment during a single testing session. Relative to the inert treatment, rodents given the hormone were less responsive and made more errors. Pregnenolone also caused a drug interaction when combined with the medications. It enhanced the performance-decreasing effects of sedative drugs. These changes could reduce the safety of sleeping pills.
Drug Interactions
Human studies assessing pregnenolone have shown similar interactions. A 2004 paper in "Psychoneuroendocrinology" tested the supplement in two trials. The first study looked at safety measures. Subjects received either the supplement or placebo for four weeks and then crossed over into the opposite condition. No adverse effects of pregnenolone on well-being, memory, mood or sleep were found. The second study looked at drug interactions. Subjects received a single dose of diazepam, an anti-anxiety medication, following the first study. Four weeks of pregnenolone use reduced the immediate effects of diazepam. Patients should carefully weight the benefits and risks of this supplement.
References
- "Proceedings of the National Academy of Sciences"; Memory-Enhancing Effects in Male Mice of Pregnenolone and Steroids Metabolically Derived From It; James F. Flood, et al.; March 1, 1992
- "Neuropsychopharmacology"; Proof-of-Concept Trial with the Neurosteroid Pregnenolone Targeting Cognitive and Negative Symptoms in Schizophrenia; Christine E. Marx, et al.; July 2009
- "Psychopharmacology"; Effects of Pregnanolone Alone and in Combination With Other Positive GABA A Modulators on Complex Behavior in Rats; Lisa R. Gerak, et al.; April 2004
- "Psychoneuroendocrinology"; Chronic Pregnenolone Effects in Normal Humans; Sharon E. Meieran, et al.; May 2004
