Centella asiatica is an herbal medicine used in Ayurvedic and traditional Chinese medicine that is commonly used as a cognitive enhancer. Some clinical studies suggest modest benefits in a few cognitive functions, but a large meta-analysis failed to show significant improvements. Centella asiatica contains bioactive compounds that provided numerous benefits for brain health in laboratory studies, but these haven't been confirmed in humans. Centella asiatica is considered to be safe with mild side effects, although a few cases of liver toxicity have been reported.
Centella asiatica has been tested in numerous clinical trials, though all of the studies were small. Our search identified:
Small clinical trials have shown potential benefit for a few cognitive functions with Centella asiatica treatment [1]; however, a meta-analysis of 11 randomized controlled trials testing its effects reported no significant differences between treatment and placebo on any cognitive functions [2]. In an exploratory clinical study of patients with post-stroke vascular cognitive impairment, treatment with Centella asiatica extract did not improve overall cognitive functions compared to that observed with folic acid treatment [3]. However, delayed recall memory was significantly improved in patients treated with Centella asiatica compared to folic acid. No differences were seen in other cognitive functions, including executive function, naming, attention, language, abstraction, or orientation.
In preclinical models of Alzheimer's disease, extracts of Centella asiatica decreased beta-amyloid levels and oxidative stress [4], prevented the shrinkage of neuronal processes [5], and protected against beta-amyloid-associated toxicity and behavioral abnormalities [6]. In models of cognitive decline, Centella asiatica treatment significantly improved memory performance, decreased markers of cell death, increased antioxidant defense, and reversed mitochondrial deficits [5][7][8]. There are many components to Centella asiatica, of which Asiatic acid has been the most studied in preclinical models. Asiatic acid does cross the blood-brain-barrier? and produces antioxidant and neuroprotective effects [9], though these findings have not been confirmed in humans.
No studies have reported whether Centella asiatica can improve cognitive function or slow decline in people with dementia. In preclinical models of Alzheimer's disease, extracts of Centella asiatica lowered behavioral deficits, reduced biological markers of Alzheimer's disease, protected against toxicity from beta-amyloid, reduced oxidative stress, and prevented the shrinkage of neuronal processes [4][5][6][9].
In a meta-analysis of 11 randomized controlled trials testing the effects of Centella asiatica on cognitive function, no adverse effects were reported in any studies testing it alone [2]. In combination therapies, side effects were comparable to or lower than those for placebo and included gastrointestinal discomfort, flatulence, nausea, headache, decreased appetite, sedation, and rash. Other studies have reported constipation, abdominal bloating, and itchiness [3].
There has been a report of three women who developed jaundice and hepatitis after taking Centella asiatica for 20-60 days [10]. They improved after discontinuation and treatment with a bile acid. It is unclear whether the liver toxicity is associated with a specific brand, preparation, or dose. People with liver disease should not take Centella asiatica.
Drug interactions are not well-documented, though theoretically, Centella asiatica may interact with antiepileptic drugs (e.g., phenytoin, valproate, and gabapentin) [11].
NOTE: This is not a comprehensive safety evaluation or complete list of potentially harmful drug interactions. It is important to discuss safety issues with your physician before taking any new supplement or medication.
Centella asiatica is an herbal medicine used in Ayurvedic and traditional Chinese medicine. It is also known as gotu kola, Asiatic pennywort, Indian pennywort, jal brahmi, mandookaparni, and tsubokusa. Gotu kola is available over-the-counter as whole herbs, powder, capsules, or liquid extracts. Dose ranges noted in Drugs.com are 30-90 mg/day for extracts and 1.5-4.0 g/day for the crude form, but much higher doses have been used in clinical studies [3]. A review on Centella asiatica noted that the extraction method, biochemical profile, and dosage information of the extract are not standardized [12], and therefore potencies and qualities may vary across preparations.
Information on dosing, side effects, and drug interactions with Centella asiatica (Gotu kola) from Drugs.com
Check for drug-drug and drug-supplement interactions on Drugs.com