evipedia.ai
← Back

40 Hz Ultrasound for Health & Longevity

Created on 10/30/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 5.5 – Audit

40 Hz ultrasound is a drug-free brain-stimulation method sending sound waves too high to hear through the skull in bursts forty times a second to drive a fast brain rhythm that weakens in Alzheimer's disease. Evidence is almost entirely from animals; no published study has tested it in people. Benefits for healthy longevity are unproven, risks at careful settings look small but poorly measured, and it remains a research tool. (Full Review)

Protocol

No human regimen
No human 40 Hz ultrasound protocol exists
No clinic or practitioner offers 40 Hz ultrasound; published protocols come from laboratories
Unfocused low-intensity protocol (Kim)
300 kHz carrier, 40 Hz pulse rate
3-millisecond pulses, 10 seconds on and 30 seconds off, 2 hours daily for 14 days in mice
Competing human approaches
Whole-brain pulsed ultrasound or 40 Hz light-and-sound
Ultrasound 1 hour three times weekly, repeated every 3 months; or light-and-sound 1 hour daily
Time to effect
Cognition (related human ultrasound)
3 months to 72 weeks
Measurement timepoints in human trials; no reliable human benefit
Depressive symptoms (transcranial pulse stimulation)
3 months
Indirect evidence; an uncertain signal
Plaque and rhythm changes (mice)
5–14 daily sessions
Mouse data only

Benefits

Contraindications
  • Compromised thermoregulation, vascular vulnerabilities, or recent ultrasound contrast agents
  • Skull defects, craniotomy, or metal implants in the beam path (aneurysm clips, cochlear implants)
  • Epilepsy or prior unprovoked seizure
  • Cerebral amyloid angiopathy, prior brain hemorrhage, or microbleeds on baseline MRI
  • Pregnancy
    •
Key Interactions
Theoretical (inferred from mechanism)
  • Anticoagulants and antiplatelet drugs (warfarin, clopidogrel)
  • Over-the-counter antiplatelet pain relievers (aspirin, ibuprofen)
  • GABA-enhancing sedatives (lorazepam, zolpidem)
  • Seizure-threshold-lowering drugs (bupropion, tramadol)
  • Anti-amyloid antibodies (lecanemab, donanemab)
  • Antiplatelet supplements (fish oil, Ginkgo biloba)
  • Other 40 Hz stimulation (light-and-sound devices)
    •

Risk & Side Effects

  • High:
  • Medium:
  • Low: Transient Headache, Neck Pain and Scalp Sensations; Audible Buzzing During Stimulation
    •
  • Speculative: Microbleeds and Tissue Injury at High Intensity; Skull and Scalp Heating; Rise in Soluble Amyloid-Beta; Reduced Vessel Signaling in Older Brains
    •

Monitoring

Marker Target Why
Brain MRI with SWI (microbleed count) No established target; track new microbleeds against own baseline scan Safety check: new microbleeds stop use
Plasma p-tau217 No established target; track change from own baseline Defines amyloid status; expected to change
Plasma Aβ42/40 ratio No established target; track change from own baseline Expected to change if amyloid clearance occurs
Resting EEG 40 Hz power No established target; track change from own baseline Measures the 40 Hz brain response
Montreal Cognitive Assessment (MoCA) Not specified in the ER Cognitive screen
Hearing check Not specified in the ER Documents whether the pulses are audible

Cadence: Baseline before any research use; symptom questionnaire after every session; cognitive testing at 2, 6 and 10 weeks; plasma biomarkers at the end of each course, then every 6–12 months; repeat MRI after the first course or with any new neurological symptom

Qualitative Assessment

  • Headache, neck pain or scalp warmth after sessions
  • Loudness of the perceived buzz during sessions
  • Sleep quality and daytime alertness
  • Memory and word-finding in daily life
  • Mood and anxiety
Not medical advice. Educational distillation of a single evidence review. Confirm any decision with a qualified clinician, especially in the presence of prescription drugs or chronic conditions.