Microdosing Ketamine for Health & Longevity - Quick Reference Sheet

Microdosing Ketamine for Health & Longevity

Created on 09/22/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 5 – Audit

Ketamine is a prescription anesthetic medication. Microdosing means taking very small amounts on a repeating schedule at home, mainly to lift low mood. Controlled research shows ketamine lifts low mood quickly at larger doses; whether the very small at-home amounts do is unsettled, and the best comparison suggests they work less well. Bladder damage, memory problems and dependence cluster at far heavier use; the safe ceiling is unmapped. (Full Review)

Protocol

Starting Dose
10 mg sublingual
Racemic ketamine, held 5 minutes then swallowed; titrated upward only if no effect. Compounded troches commonly 25–100 mg.
Frequency
1–3× weekly
Every 2–3 days or weekly in the original protocol. Daily dosing is the fastest route to tolerance and dependence.
Best Time of Day
Evening, at rest
A 2–4 hour fast reduces nausea; no driving during the 60–90 minute peak. Late afternoon where activation occurs rather than sedation.
Time to effect
Mood
Hours
Usually evident within 24 hours of the first effective dose.
Sustained Benefit
2–4 weeks
Emerges only on a repeated schedule, not from a single dose.
Sleep Depth
First night
Slow-wave sleep and slow-wave activity increase after dosing.

Benefits

Contraindications
  • Uncontrolled hypertension (above 160/100 mmHg)
  • Intracranial aneurysm or arteriovenous malformation
  • Unstable angina or myocardial infarction within 90 days
  • NYHA Class III–IV heart failure
  • Personal or first-degree-relative history of psychotic disorder
  • Current mania
  • Active substance use disorder (dissociatives, alcohol)
  • Hepatic impairment (Child-Pugh B or C)
  • Interstitial cystitis or unexplained urinary symptoms
  • Pregnancy and breastfeeding
  • Severe untreated obstructive sleep apnea
  • Inability to rest, not driving, for two hours after dosing
Key Interactions
  • Benzodiazepines (lorazepam, diazepam, clonazepam)
  • Opioid antagonists (naltrexone, naloxone)
  • CYP3A4 inhibitors (ketoconazole, ritonavir, grapefruit juice)
  • CYP3A4 / CYP2B6 inducers (rifampicin, carbamazepine, St John's wort)
  • Sympathomimetics and stimulants (amphetamine, methylphenidate, high-dose caffeine)
  • Other CNS depressants (alcohol, opioids, gabapentinoids, sedating antihistamines)
  • Monoamine oxidase inhibitors (phenelzine, tranylcypromine, selegiline)
  • Supplements with additive blood-pressure or sedative effects (nitrates, magnesium, potassium, valerian, kava, high-dose melatonin)
  • Supplements acting on the same pathway (magnesium, zinc, agmatine, theanine, rapamycin)
  • Other interventions (psychedelic-assisted therapy, transcranial magnetic stimulation, electroconvulsive therapy)

Risk & Side Effects

  • High: Dissociation and perceptual disturbance; transient increase in blood pressure and heart rate; nausea, vomiting, dizziness and sedation; misuse, tolerance and dependence potential
  • Medium: Ketamine-associated uropathy; cognitive impairment with frequent or high-dose use; hepatobiliary injury and liver enzyme elevation; hazards specific to unsupervised at-home administration
  • Low: Tachyphylaxis and diminishing response; precipitation of mania, psychosis or persistent perceptual disturbance; disrupted sleep and next-day activation; raised intraocular and intracranial pressure
  • Speculative: Emotional blunting with sustained daily use; unknown effects of decade-scale exposure

Monitoring

Marker Target Why
Blood Pressure 110–120 / 70–80 mmHg at rest Main cardiovascular effect; defines safe ceiling
Resting Heart Rate 50–70 bpm Tracks sympathetic activation and stimulant load
ALT and AST ALT 10–26 U/L (women), 10–33 U/L (men); AST 10–26 U/L Detects liver-cell injury from repeated exposure
GGT <20 U/L (women), <25 U/L (men) Earliest marker of biliary irritation
Serum Creatinine and eGFR eGFR above 90 mL/min/1.73 m² Upper tract involvement if injury progresses
Urinalysis (dipstick and microscopy) No blood, no leukocytes, no protein Earliest sign of bladder injury; reversible early
hs-CRP Below 1.0 mg/L Baseline inflammatory status
Fasting Glucose and HbA1c Glucose 75–86 mg/dL; HbA1c 4.8–5.2% Confirms no glucose drift with repeated use

Cadence: Blood pressure before and 20 minutes after every dose for the first month, then monthly; urinary symptom review at 4 weeks, then every 3 months; blood panel at 3 months, then every 6 months; cognitive baseline annually, or sooner over 65.

Qualitative Assessment

  • Mood level and stability: day-to-day variability, not just how low or high
  • Sleep quality and continuity: time to fall asleep, night wakings, how rested the morning feels
  • Cognitive clarity: word-finding and short-term memory; any deterioration is a stop signal
  • Urinary symptoms: frequency, urgency, suprapubic discomfort, asked explicitly
  • Emotional range: whether positive and negative feelings are both intact, or affect is flattening
  • Relationship to the dose: anticipation between doses, or resistance to the thought of stopping