Several studies have shown that piracetam improves cognitive functions in older people, though many of the studies are dated and used subjective measures of cognitive functions.
In healthy, older people, one controlled clinical trial reported improvement in visual perception, attention, function, and acuity [1], while a larger controlled trial failed to show significant improvement in 10 different cognitive tests when compared to placebo [2]. In cognitively impaired older adults, piracetam treatment was associated with clinical improvement based on a meta-analysis of numerous randomized controlled trials [3]. However, in most studies the measurements used were crude and did not test specific cognitive functions. In a controlled clinical trial of psychiatric patients with mild cerebral impairment, piracetam treatment improved overall functioning, particularly alertness, socialization, and cooperation, relative to the control group [4]. In a meta-analysis of randomized controlled trials in post-stroke patients, piracetam treatment did not improve overall severity of aphasia, but the treatment was associated with improvement in written language [5].
In preclinical studies, piracetam enhances the fluidity of plasma membranes and membranes of brain mitochondria. Several studies have shown that piracetam enhances mitochondrial function and energy production while reducing cell death [6][7]. Piracetam can also protect against oxidative stress and the harmful effects of beta-amyloid in model systems [8][9]. Theoretically, this could protect neurons from damage, reducing cognitive impairment and dementia risk.
For Dementia Patients
In two double-blind randomized controlled trial of Alzheimer's patients, piracetam treatment did not result in improvement in cognitive functions [10][11]. A double-blind randomized controlled trial of 20 people with Parkinson's dementia also reported that piracetam treatment failed to improve cognitive or neurological measures [12].