Vinpocetine

Cognitive impairment and dementia

• Cochrane review 2003 (search updated March 2009), 3 trials, 583 people with dementia. All included trials were run before or in the early 1990s with older diagnostic criteria. Vinpocetine at 30 and 60 mg a day did better than placebo, but few patients were treated for six months or more, only one trial lasted a year, adverse effects were inconsistently reported and no intention-to-treat data were available; the reviewers concluded that the evidence is inconclusive and does not support clinical use (PMID: 12535455).
• Hindmarch 1991, 203 outpatients with mild to moderate organic psychosyndromes, including primary dementia, 16 weeks, double-blind, placebo-controlled. Patients took 10 mg or 20 mg three times a day, or placebo. Both doses beat placebo on the two confirmatory endpoints, global improvement on the CGI scale and cognitive performance on the SKT test, and adverse event frequencies were comparable (PMID: 2071888).
• Balestreri 1987, 84 older patients with chronic vascular cerebral dysfunction, 90 days, double-blind, placebo-controlled. Patients took 10 mg three times a day for 30 days and then 5 mg three times a day for 60 days, or placebo; scores on the CGI, SCAG and Mini-Mental Status Questionnaire favored vinpocetine, with no serious side effects. The abstract does not name a primary endpoint (PMID: 3553281).
• Thal 1989, 15 people with Alzheimer's disease, open-label pilot, one year. Doses of 30, 45 and 60 mg a day did not improve cognition or global function, and patients declined at the same rate as a matched control group (PMID: 2715559).
• Kemeny 2005, 26 patients with multiple cerebral infarcts, double-blind, placebo-controlled, 3 months. Apart from one digit span test, neuropsychological results did not differ from placebo (PMID: 16100299).

Healthy volunteers

• Subhan and Hindmarch 1985, 12 healthy women, double-blind crossover. After two days of 10, 20 or 40 mg three times a day, memory scanning on the Sternberg test improved at 40 mg, with no change in critical flicker fusion, reaction time or subjective drug effects (PMID: 3899677).
• Bhatti and Hindmarch 1987, 8 volunteers. Pretreatment with 40 mg modestly improved short-term memory processes impaired by flunitrazepam (PMID: 3693872).
• Meador 2021, 8 healthy adults and 8 adults with focal epilepsy, double-blind crossover. Single doses up to 60 mg in healthy adults, and a single 20 mg dose followed by one month of open-label 20 mg three times a day in epilepsy, produced no significant cognitive benefit, and blood levels were lower than in mice given doses effective in an animal model (PMID: 33957389).

Acute ischemic stroke

• Cochrane review 2008, 2 trials, 70 participants. Death or dependency did not differ at one and three months, the confidence intervals were wide, and the reviewers found not enough evidence to judge the effect of vinpocetine (PMID: 18253980).
• CAVIN 2016, China, 610 patients, open-label, randomized. Patients received standard care with or without intravenous vinpocetine 30 mg a day for 7 days (469 against 141 patients). MMSE, NIHSS and Barthel scores favored vinpocetine at 90 days, with no difference in safety (PMID: 27283947). The ClinicalTrials.gov record lists MMSE and the modified Rankin scale as primary outcomes, a planned 960 patients and Gedeon Richter as a collaborator, while the abstract reports no modified Rankin result (ClinicalTrials.gov NCT01400035; PMID: 27283947).
• Meta-analysis 2022. Four randomized trials, described by the authors as placebo-controlled, with 601 patients on vinpocetine and 236 controls, found less death or significant disability at one month (relative risk 0.80) and three months (relative risk 0.67); the authors called for larger double-blind trials before routine use (PMID: 35488169).

Epilepsy

• Garza-Morales 2019, Mexico, 87 patients with focal epilepsy, double-blind, placebo-controlled. Extended-release vinpocetine at 2 mg/kg a day, added to one to three antiseizure drugs, reduced seizures more than placebo over an 8-week evaluation phase (p<0.0001): 69 percent of vinpocetine patients had a 50 percent reduction against 13 percent on placebo, and adverse effects did not differ significantly (PMID: 31536041).

Brain blood flow

• Bonoczk 2002, 43 stroke patients, double-blind, placebo-controlled, single infusion. A single 20 mg intravenous infusion raised Doppler spectral intensity and deoxygenated hemoglobin more than placebo, which the authors read as higher perfusion and oxygen extraction, while blood flow velocity did not differ; the first author was at Gedeon Richter (PMID: 12044859).
• Szilagyi 2005, 13 patients with chronic ischemic stroke, double-blind PET study. Fourteen days of infusions containing vinpocetine shifted regional blood flow more than infusions without it (PMID: 15760651).

Pregnancy

On 3 June 2019 the FDA advised pregnant women and women who could become pregnant not to take vinpocetine, because data it reviewed linked vinpocetine to adverse reproductive effects: vinpocetine may cause a miscarriage or harm fetal development (FDA, Vinpocetine in Dietary Supplements). In National Toxicology Program studies, pregnant rats given 60 mg/kg a day by mouth had more post-implantation loss and resorptions, lower fetal weights and fewer live fetuses without maternal toxicity, and fetal ventricular septal defects rose with dose; pregnant rabbits had more loss and fewer live fetuses at 300 mg/kg and lower fetal weights from 75 mg/kg (PMID: 29460393). A 2023 rat embryo culture study found embryonic slowing of the heart from 100 nanomolar, a concentration the authors judged unlikely to be reached at typical human doses, and suggested that the FDA statement may cause undue anxiety (PMID: 37753450).

Heart rhythm

Vinpocetine blocks the cardiac IKr potassium current in laboratory studies, and block of this current can cause the arrhythmia torsade de pointes, according to the 2023 University of Sydney paper (PMID: 37753450).

Product quality

In a 2015 test of 23 US supplements labeled as containing vinpocetine, 6 contained none and 17 contained 0.3 to 32 mg per recommended daily serving (PMID: 26426301). A 2021 analysis of 10 cognitive enhancement supplements detected vinpocetine among five unapproved drugs and found that several detected drugs were not declared on the labels (PMID: 34484905).