Well-studied herb with strong evidence for modest cognitive benefits in dementia and mild cognitive impairment. The research specifically uses pharmaceutical-grade standardized extracts, not traditional preparations.
Traditions: Traditional Chinese Medicine (seeds, not leaves), German phytotherapy (modern, standardized leaf extracts)
Approved standardized Ginkgo biloba extract for cerebral insufficiency, intermittent claudication, and vertigo as a recognized medicine in Germany.
WHO-recognized medicinal plant monograph for symptomatic treatment of mild to moderate cerebrovascular insufficiency, improvement of pain-free walking distance in peripheral arterial occlusive disease, and treatment of inner ear problems including tinnitus.
Traditional use focused on Ginkgo seeds (Bai Guo) for respiratory and urinary conditions, not leaves. Seeds contain ginkgotoxin and require careful processing. Modern pharmaceutical use of leaf extracts represents a departure from traditional applications.
Strong evidence for cognitive benefits in dementia from multiple large trials. A meta-analysis of 18 RCTs with 1,642 Alzheimer's patients found 23% better clinical response when combining 240 mg daily standardized extract with medication versus medication alone [1]. MMSE scores improved by 3.02 points on average [1]. For mild cognitive impairment, 79% of 160 adults taking 240 mg daily for 24 weeks achieved meaningful neuropsychiatric symptom reduction versus 56% on placebo [2]. A pilot study with 9 healthy elderly found cerebral blood flow increased 15% in white matter and 13% in gray matter after 4 weeks at 120 mg daily [3]. Tinnitus trial with 197 participants found meaningful improvement at 240 mg daily for 12 weeks, with better tolerability than comparison drug [4]. Critical requirement: standardized extracts with 22-27% flavonoids, 5.4-6.6% terpene lactones, <5 ppm ginkgolic acids. Clinical trials show no significant bleeding risk despite theoretical concerns - 18+ RCTs with 1,985+ participants found no higher bleeding risk than placebo [1].
18 RCTs with 1,642 participants: 240 mg daily EGb 761 plus donepezil showed 23% better clinical response (RR 1.23, 95% CI 1.13-1.34) versus donepezil alone. MMSE improved 3.02 points (95% CI 2.14-3.89). Activity of Daily Living Scale decreased 4.56 points (95% CI -5.09 to -4.03) indicating functional improvement. No increased adverse reactions (RR 0.91, 95% CI 0.58-1.42). Duration: 22-26 weeks typical.
160 adults with MCI taking 240 mg EGb 761 daily for 24 weeks: NPI composite score reduced 7.0 ± 4.5 points versus 5.5 ± 5.2 on placebo (p=0.001). Clinical improvement: 78.8% achieved ≥4 point NPI decrease versus 55.7% on placebo (p=0.002). Anxiety scores and Trail-Making Test (processing speed) statistically significant. Safe and well tolerated.
9 RCTs with 2,561 participants over 22-26 weeks: 240 mg/day EGb 761 able to stabilize or slow cognitive decline. Improvements in cognition, function, behavior. Safety data revealed no important safety concerns with EGb 761.
9 healthy elderly men (mean age 61±10 years) taking 60 mg twice daily (120 mg total) for 4 weeks: white matter CBF increased 15% globally (P≤0.0001), gray matter CBF increased 13% globally (P≤0.0001). Measured using dynamic susceptibility contrast-enhanced MRI.
197 participants (99 ginkgo, 98 pentoxifylline): 120 mg EGb 761 twice daily (240 mg total) for 12 weeks produced significant improvements in tinnitus questionnaire scores including loudness/annoyance scales, anxiety, disability measures. Adverse events: 20 in ginkgo group versus 36 in pentoxifylline group. No serious adverse events. Better tolerability for EGb 761.
20 healthy young volunteers tested with 120 mg, 240 mg, and 360 mg acute single doses: speed of attention factor showed dose-dependent improvement at 240 mg and 360 mg doses, demonstrable at 2.5 hours and persisting through 6 hours versus placebo. Effects dose-dependent though not linear.
Most robust evidence for Alzheimer's disease and MCI. 18 RCTs with 1,642 Alzheimer's patients used this dose combined with donepezil, showing 23% better clinical response [1]. 160 adults with MCI showed 78.8% clinical improvement at 24 weeks [2]. Must be pharmaceutical-grade standardized to 22-27% flavonoids, 5.4-6.6% terpene lactones, <5 ppm ginkgolic acids. EGb 761 or equivalent. Duration: minimum 22-26 weeks in trials for sustained cognitive benefits.
Pilot study with 9 healthy elderly adults showed 15% white matter and 13% gray matter CBF increase after 4 weeks [3]. Lower dose than cognitive impairment protocols.
Trial with 197 participants over 12 weeks showed significant improvements in loudness, annoyance, anxiety, and disability measures [4]. Better tolerability than pentoxifylline comparison drug (20 adverse events versus 36).
Healthy young volunteers showed improved attention starting at 2.5 hours and lasting up to 6 hours [5]. Dose-dependent effects. Different from sustained cognitive benefits that develop over months. Not recommended for chronic use at 360 mg dose.
Ginkgo leaf extract has substantial research backing for cognitive support, particularly in older adults with memory concerns. This isn’t “promising preliminary results” - actual rigorous RCTs with meaningful sample sizes showing specific effects.
Alzheimer’s Disease - Strong Evidence:
Mild Cognitive Impairment - Strong Evidence:
Cerebral Blood Flow - Pilot Evidence:
Tinnitus - Moderate Evidence:
Acute Cognitive Effects:
Critical requirement: All positive trials used standardized extracts containing 22-27% flavonoids and 5.4-6.6% terpene lactones, with ginkgolic acids reduced to <5 ppm. This standardization appears essential - studies using crude leaf preparations lack the same evidence.
Traditional use of Ginkgo represents a complicated picture because modern pharmaceutical applications differ significantly from historical use.
Traditional Chinese Medicine (Seeds, Not Leaves): In Traditional Chinese Medicine, Ginkgo seeds (called Bai Guo) were historically used for respiratory and urinary conditions - not cognitive support and not using the leaves. The seeds contain ginkgotoxin (4-O-methylpyridoxine), which can cause seizures in large amounts and requires careful processing. Traditional TCM use focused on seeds for completely different indications than what modern research investigates.
Modern Development (Mid-20th Century Onward): Modern pharmaceutical use of Ginkgo represents a relatively recent development focusing on standardized leaf extracts rather than traditional seed preparations. The German Commission E approved Ginkgo leaf extract in 1998, and WHO recognized it in 1999 - both for cognitive and circulatory applications that differ from classical TCM indications.
German Commission E (1998): Approved standardized Ginkgo biloba extract for cerebral insufficiency, intermittent claudication, and vertigo as a recognized medicine in Germany [8]. This represents modern phytotherapy rather than traditional herbalism.
WHO Monographs (1999): WHO-recognized medicinal plant monograph for symptomatic treatment of mild to moderate cerebrovascular insufficiency, improvement of pain-free walking distance in peripheral arterial occlusive disease (PAOD), and treatment of inner ear problems including tinnitus [9]. Again, this is modern clinical recognition rather than ancient traditional use.
Important distinction: If you’re looking for information about traditional Chinese herbal uses of Ginkgo seeds, this page won’t have it. The evidence here comes from contemporary clinical trials of leaf extracts (specifically 22-26 week trials with 240 mg daily standardized preparations [1][2][3]), not ethnobotanical or historical sources. Traditional and modern uses represent largely separate traditions with different plant parts, preparations, and indications.
The clinical evidence points to standardized extract capsules as the only reliably effective preparation. Forget tea or tincture - the trials used concentrated pharmaceutical-grade extracts.
For cognitive support in Alzheimer’s or MCI:
240 mg daily of standardized extract, either as 120 mg twice daily or 240 mg once daily. Both schedules showed comparable results in trials [1][2][3]. This is the dose where 18 RCTs with 1,642 Alzheimer’s patients found 23% better clinical response when combined with standard medication [1], and where 78.8% of 160 adults with MCI achieved meaningful neuropsychiatric symptom improvement at 24 weeks [2].
You’re looking at a minimum 22-26 weeks (roughly 5-6 months) before expecting noticeable sustained benefits. One trial showed measurable changes at 24 weeks [2]. This isn’t something that works overnight - effects build over months.
Critical specifications to look for on the label:
Take with or without food - trials didn’t specifically test this, so either appears fine. Some people find it easier on the stomach with food.
For cerebral blood flow:
60 mg twice daily (120 mg total) - the pilot study used this lower dose and saw 15% white matter and 13% gray matter CBF increase at 4 weeks [4]. Lower dose than cognitive impairment protocols.
For tinnitus:
120 mg twice daily (240 mg total) for 12 weeks - trial with 197 participants showed significant improvements in loudness, annoyance, and disability measures with better tolerability than the comparison drug [5].
For acute cognitive effects:
Single doses of 240-360 mg showed improved attention starting around 2.5 hours and lasting up to 6 hours in healthy young adults [6]. But these acute effects differ from the sustained cognitive benefits that develop over months with daily use. Don’t use 360 mg daily chronically - that dose hasn’t been studied long-term and isn’t superior to 240 mg for sustained benefits.
Why not tea or tincture?
A tea would need roughly 12 grams of dried leaf to match 240 mg of 50:1 extract, and even then the extraction efficiency in water is poor for the key compounds. Plus, teas contain higher levels of ginkgolic acids, which can cause allergic reactions. Raw leaf powder has the same problem - no standardization, unknown ginkgolic acid content. The clinical evidence showing 23% better clinical response [1] and 78.8% improvement rates [2] is specific to concentrated, standardized extracts meeting pharmaceutical standards.
For cognitive support, you won’t notice changes day-to-day. Track your baseline before starting:
Memory tasks:
Processing speed:
Attention:
Functional abilities:
Neuropsychiatric symptoms (if you have MCI):
For tinnitus:
Reassess timing:
Side effects to monitor:
RED FLAGS - Stop immediately:
What they might report (based on trials): “I can remember my grocery list without checking it three times,” “Balancing my checkbook doesn’t take as long,” “Background noise doesn’t derail my conversations as much.”
Use with caution and monitoring:
Drug interaction reassurance:
The difference between products matters significantly here. All the positive clinical trials showing 23% better clinical response [1] and 78.8% improvement rates [2] used extracts meeting specific pharmacopoeia standards - mainly EGb 761, a proprietary extract, or equivalent standardized products.
What standardization means:
These extracts concentrate the leaves 35-67 times (meaning 35-67 kg of leaves per 1 kg of extract) using 60% acetone solvent. This process ensures consistent levels of the active compounds: flavonoids (quercetin, kaempferol, isorhamnetin) and terpene lactones (ginkgolides A, B, C and bilobalide). Critically, it also removes most of the ginkgolic acids, which cause allergic reactions and have cytotoxic properties.
The standardization gap is real:
Products that don’t specify “standardized to 22-27% flavonoids and 5.4-6.6% terpene lactones” likely don’t match what was studied in trials showing 3.02-point MMSE improvement [1] and 15% cerebral blood flow increase [4]. “Ginkgo biloba leaf powder 500 mg” with no other specifications is not the same thing as the pharmaceutical-grade extracts used in the 18 RCTs with 1,642 participants [1].
Why ginkgolic acid content matters:
Ginkgolic acids are alkylphenolic compounds naturally present in Ginkgo leaves that can cause allergic reactions and have cytotoxic properties. Pharmaceutical-grade extracts reduce these to <5 ppm through processing and purification. Non-standardized products may contain high levels causing allergic skin reactions, contact dermatitis, and potential cytotoxic effects with chronic exposure. All high-quality clinical trials showing excellent safety profiles [1][2][3] used standardized extracts with <5 ppm ginkgolic acids.
Third-party testing adds confidence:
ConsumerLab, USP, and NSF all verify that products contain what the label claims and are free from contaminants like heavy metals and pesticides. Given that herbal supplements are poorly regulated, this verification matters when you’re committing to 22-26 weeks of daily use.
What to look for:
Form considerations:
Red flags - Avoid:
Either branded EGb 761 products or properly standardized generic extracts should work, as long as the standardization specifications match the clinical trial standards. The evidence supports the standardization markers (22-27% flavonoids, 5.4-6.6% terpene lactones, <5 ppm ginkgolic acids), not necessarily the brand.
Donepezil (pharmaceutical): Extensively studied combination - 18 RCTs with 1,642 Alzheimer’s patients showed 23% better clinical response (RR 1.23, 95% CI 1.13-1.34) when combining 240 mg ginkgo daily with donepezil versus donepezil alone [1]. MMSE improved by 3.02 points on average [1]. No statistically significant difference in adverse reactions (RR 0.91, 95% CI 0.58-1.42) [1]. This combination has strong evidence for additive benefits without increased safety concerns.
Aspirin or anticoagulants: Monitor closely though clinical trials show no significant bleeding risk. Meta-analysis of 18+ RCTs with 1,985+ participants found no higher bleeding risk than placebo based on hemostasis parameters [1]. Theoretical PAF antagonism warrants monitoring INR if on warfarin, but this is precautionary rather than based on observed clinical events. Study of 18 healthy adults found no relevant CYP450 interactions at 240 mg daily [7], so unlikely to affect anticoagulant metabolism.
Ginkgo leaf extract has strong evidence for modest cognitive benefits in older adults with memory impairment, based on trials with over 2,500 participants. You’re looking at 240 mg daily of standardized extract for 22-26 weeks (5-6 months) to see sustained effects.
The case for trying it: Strong Alzheimer’s evidence (18 RCTs with 1,642 participants showing 23% better clinical response when added to medication [1]). MCI evidence (78.8% of 160 adults achieved meaningful neuropsychiatric symptom reduction at 24 weeks [2]). Meta-analysis of 9 trials with 2,561 participants found ability to stabilize or slow cognitive decline [3]. Excellent safety profile - adverse event rates comparable to placebo across 18+ trials with 1,985+ participants [1], no significant bleeding risk despite theoretical concerns [1], no relevant drug interactions at 240 mg daily [7]. Safe and well tolerated in elderly populations (most trial participants age 60-85 years) [1][2][3].
The limitations: The improvement is real but modest - about 3 points on MMSE scale [1], which you might experience as slightly better word recall or less time to complete familiar tasks. Effects take months to assess (22-26 weeks in trials [1][2][3]), not immediate. You need pharmaceutical-grade standardized product (22-27% flavonoids, 5.4-6.6% terpene lactones, <5 ppm ginkgolic acids) - traditional tea or unstandardized powder isn’t equivalent. About 21.2% of MCI patients didn’t achieve meaningful response at 24 weeks [2], so it’s not universal. Quality varies significantly in commercial supplements - products without standardization specifications likely don’t match what was studied.
When it might work (if it works): Memory tasks feel slightly easier (remembering lists, names, phone numbers). Routine tasks take less time (paying bills, following recipes). Conversations in noisy environments don’t require as much concentration. If you have MCI with anxiety, you notice anxiety levels decreasing alongside cognitive improvements [2]. Functional abilities in daily living improve (cooking, managing medications, household tasks [1]). Changes are gradual over months, not sudden transformations.
When to skip it: You have contraindications (pregnancy, breastfeeding, known Ginkgo allergy, children). You need immediate symptom relief (effects take 22-26 weeks [1][2][3]). You have severe cognitive impairment needing pharmaceutical intervention. You’re unwilling to commit to pharmaceutical-grade products and 5-6 month trial period. You’re seeking dramatic cognitive transformation rather than modest functional improvements.
Safety profile: Meta-analysis of 18 Alzheimer’s trials with 1,642 participants: no statistically significant difference in adverse reactions between ginkgo + medication and medication alone (RR 0.91, 95% CI 0.58-1.42) [1]. Meta-analysis of 9 cognitive impairment trials with 2,561 participants: “Safety data revealed no important safety concerns with EGb 761” [3]. Tinnitus trial with 197 participants: 20 adverse events in ginkgo group versus 36 in comparison drug group, no serious adverse events [5]. No significant bleeding risk in clinical trials despite theoretical concerns - 18+ RCTs with 1,985+ adults found no higher bleeding risk than placebo [1]. Drug interaction study: no relevant CYP450 effects at 240 mg daily [7]. When side effects occur: mild stomach upset, headache, dizziness at rates similar to placebo [1][2][3].
If trying: Use standardized capsules (22-27% flavonoids, 5.4-6.6% terpene lactones, <5 ppm ginkgolic acids, third-party tested) at 240 mg daily (120 mg twice daily or 240 mg once daily). Assess at 8 weeks for early response signals, full assessment at 22-26 weeks. If no benefit by 8 weeks, you’re likely a non-responder for that indication. Track subjective functional changes (how tasks feel, time to complete routine activities) more than trying to measure objective cognitive scores. Monitor for side effects though they occur at placebo rates in trials. If on anticoagulants, monitor INR as precaution though clinical evidence shows no significant interaction.
Duration: Minimum 22-26 weeks (roughly 5-6 months) for sustained cognitive benefits in MCI or dementia based on trial durations [1][2]. Cerebral blood flow changes measurable at 4 weeks [3]. Tinnitus improvements at 12 weeks [4]. Acute attention effects within 2.5-6 hours for single doses [5]. Start assessing response at 8 weeks - if no noticeable benefit by then, you're likely a non-responder.
What to notice:
You're tracking: did memory tasks feel slightly easier? Can you complete routine tasks a bit faster? For tinnitus, is it less intrusive? Changes are modest, not dramatic - about 3 points on MMSE scale [1]. You won't notice changes day-to-day. Reassess at 8 weeks and again at 22-26 weeks when trials showed measurable changes [1][2]. Meta-analysis of 18 RCTs with 1,985+ participants found adverse event rates comparable to placebo, no serious adverse events in most trials [1]. If no benefit by 8 weeks, you're likely a non-responder for that indication.
Generally considered: safe
Contraindications:
Pregnancy/Nursing: Avoid during pregnancy - insufficient safety data, no adequate controlled studies in pregnant women, theoretical concerns about platelet function and bleeding risk during delivery. Avoid during lactation - unknown whether Ginkgo flavonoids or terpene lactones are excreted in human milk, unknown effects on nursing infant.
Excellent safety profile across 18+ RCTs with 1,985+ participants [1]. Adverse event rates comparable to placebo. Meta-analysis of 18 Alzheimer's trials: no statistically significant difference in adverse reactions between ginkgo + donepezil and donepezil alone (RR 0.91, 95% CI 0.58-1.42) [1]. Meta-analysis of 9 cognitive impairment trials with 2,561 participants over 22-26 weeks: 'Safety data revealed no important safety concerns with EGb 761' [2]. Tinnitus trial: 20 adverse events in ginkgo group versus 36 in pentoxifylline group, no serious adverse events [4]. Bleeding risk: Despite theoretical concerns about PAF antagonism, clinical trials show no higher bleeding risk than placebo based on hemostasis parameters across 1,985+ adults [1]. Some clinicians recommend discontinuing 2 weeks before surgery (precautionary, no strong clinical evidence of perioperative bleeding). Drug interactions: Study of 18 healthy adults found no relevant effect on CYP450 enzyme activity at 240 mg daily (90% confidence intervals within 0.70-1.43 range), meaning unlikely to interfere with most prescriptions [6]. Maximum safe dose: Do not exceed 240 mg daily for chronic use (300 mg studied in one trial but not superior). Acute doses up to 360 mg studied and well tolerated [5]. Use with caution: Monitor INR if on warfarin (precautionary, though no evidence of interaction). Patients with seizure disorders should monitor seizure frequency (rare case reports exist, possibly related to ginkgotoxin in poorly processed products). Pediatric use not recommended (insufficient safety data, most RCTs enrolled adults age 55-85 years). Critical quality requirement: Only use standardized extracts with <5 ppm ginkgolic acids meeting European or US Pharmacopoeia standards. Non-standardized products may contain high ginkgolic acid levels causing allergic reactions and cytotoxic effects.