Bacopa Monnieri: Dosage, Benefits and Side Effects

Bacosides are the active saponins. Proposed actions include enhanced dendritic branching in the hippocampus, modulation of acetylcholine and serotonin signalling, and antioxidant activity in neural tissue. The delayed onset is consistent with a structural or adaptive mechanism rather than an acute neurotransmitter effect.

• Memory acquisition and delayed recall: improved on the Auditory Verbal Learning Test in randomised trials in healthy older adults.
• Speed of attention and reaction time: a meta-analysis of nine randomised trials in 437 participants found shortened Trail B completion and reduced choice reaction time.
• Anxiety: reduced in some trials in older adults, alongside the cognitive measures.
• Onset: twelve weeks is the standard trial length. Five-week interim points are frequently non-significant.

Kongkeaw 2014 meta-analysis of nine randomised controlled trials covering 437 subjects, Calabrese 2008 randomised trial in healthy older adults, and Morgan 2010 in older persons. The pattern across them is consistent: real but modest improvements in memory acquisition and processing speed, at twelve weeks, at 300 mg/day.

300-450 mg/day of extract standardised to roughly 50-55% bacosides, taken with food. All the trials in the main systematic review ran for twelve weeks at 300-450 mg/day. Taking it with a meal containing fat both improves absorption and reduces the nausea that is its main tolerability issue.

GI complaints dominate: nausea, cramping, increased stool frequency, worst on an empty stomach. Dry mouth and fatigue are reported. Sedation is common enough that many people prefer to take it in the evening.

Has cholinergic activity, so caution alongside acetylcholinesterase inhibitors and anticholinergic drugs. May add to the effect of sedatives and thyroid medication. There is preliminary evidence of thyroid hormone elevation in animal work, so people on thyroid replacement should mention it to a prescriber.