Research Resource Hub

The clinical research on oral ketamine for depression was built on weight-based dosing: 1.0 mg/kg, 1.5 mg/kg, 3.0 mg/kg — dose adjusted to the patient’s body weight because ketamine distributes into body tissue and its effect depends on achieving adequate plasma concentration per kilogram of mass. Telehealth and most real-world prescribing abandoned this approach entirely, shifting to fixed doses of 150mg, 200mg, or 300mg administered to all patients regardless of weight. A 50-kilogram patient and a 130-kilogram patient receive the same amount of drug. They do not receive the same dose.

To quantify the pharmacokinetic consequences of the fixed-dose approach across a realistic range of patient body weights, identify which patients are being systematically underdosed and which are being overdosed, and establish why treatment-resistant depression patients — the primary target population for at-home oral ketamine — are disproportionately likely to fall in the underdosed range.

A fixed dose of 150mg delivers 3.0 mg/kg to a 50kg patient — at the high end of the research range — and 1.0 mg/kg to a 150kg patient, exactly at the minimum threshold tested in positive controlled trials. A 130kg patient receives 1.15 mg/kg — a dose that puts them pharmacokinetically at the floor of what research has found to be effective. The average American adult male weighs approximately 90kg and receives 1.67 mg/kg at 150mg — toward the lower end of the research range. Because patients with treatment-resistant depression are disproportionately likely to have gained weight from prior antidepressant medications, they are disproportionately likely to land in the subtherapeutic range of a fixed-dose protocol. No clinical trial has compared fixed-dose versus weight-based outcomes in oral ketamine. The shift was made without evidence that it is safe to make.

Fixed-dose oral ketamine prescribing is not a neutral administrative simplification. It is a pharmacological decision with predictable winners and losers. Lighter patients may be receiving doses that approach the upper bound of the research range; heavier patients — who are more common than the literature acknowledges — may be receiving doses that approach or fall below the minimum effective threshold. The patients most likely to be underdosed are the same patients most likely to have been prescribed oral ketamine in the first place.

Oral and sublingual ketamine is prescribed at-home to tens of thousands of patients through telehealth services and community psychiatrists. A companion scoping review identified 26 clinical studies of oral or sublingual ketamine for depression spanning 2013 to 2026. None used a once-weekly protocol. Investigation of real-world at-home prescribing reveals a fragmented landscape operating across multiple dosing models — none of which sits inside the frequency and dose parameters of the research evidence base.

To document the frequency and dose protocols used across 26 clinical studies, characterize the real-world at-home prescribing landscape in its full complexity, and analyze the specific evidence gaps created by each prescribing model — including the direction and magnitude of each model’s departure from the research record.

Secondary analysis of the Alvear 2026 scoping review dataset combined with systematic review of telehealth provider protocols, compounding pharmacy prescribing data, and a published nationwide survey of community ketamine clinics (Pacilio et al., 2025).

Zero of 26 clinical studies used a once-weekly protocol. The real-world at-home landscape divides into three distinct categories with opposite evidence problems: therapeutic-dose telehealth platforms (Wondermed, Nue Life, Mindbloom) use research-range doses (150–450mg) but frequencies of once-weekly or less; low-dose daily telehealth (Joyous, 50,000+ patients) uses daily frequency but doses (10–120mg) far below the research range; and community psychiatrists are the most variable and in some cases the most research-aligned, with compounding pharmacy data showing prescriptions of up to thrice weekly. No prescribing model has both the dose and the frequency inside the research evidence window simultaneously.

The at-home oral ketamine prescribing landscape has fragmented into models that are each wrong in opposite directions relative to the research evidence. The two major commercial telehealth models represent mirror-image failures: one has the dose but not the frequency; the other has the frequency concept but not the dose. Neither has controlled evidence for its specific combination of parameters. A head-to-head frequency trial at a controlled dose is the single most needed study in this field.

Oral and sublingual ketamine for depression is being prescribed to tens of thousands of patients through telehealth services with no FDA-approved dosing protocol, no clinical guideline covering this route of administration, and no publicly available synthesis of what clinical researchers have actually tested. A prior surveillance study of patient-reported experiences documented a 120-fold dose range among at-home users — from 10mg to 1,200mg per session — with no shared framework for interpreting what constitutes an appropriate dose.

To identify, extract, and synthesize dosing parameters — dose amount, formulation, frequency, and duration — from all available clinical studies of oral or sublingual ketamine for depression published between 2013 and 2026, and to analyze the patient safety implications of the absence of a dosing standard.

Systematic web searches across PubMed Central, medRxiv, Google Scholar, and open-access journal databases. Three sequential verification passes conducted, supplemented by reference chasing from the most recent meta-analysis (Silberbauer et al., 2026). Studies included if they involved human subjects, oral or sublingual administration, depression as a primary or secondary outcome, a reported dose amount, and a minimum sample size of three participants.

Twenty-six studies identified spanning 2013 to 2026: 9 randomized controlled trials, 5 open-label trials, 3 case series or retrospective studies, and 9 real-world or telehealth studies. Among RCTs using standard racemic ketamine, effective doses ranged from approximately 70mg per session to 180mg per session. Three studies that failed to achieve primary endpoints attributed their outcomes to insufficient dosing. No consensus exists across the literature on dose, frequency, duration, or formulation. Real-world telehealth protocols use frequencies — typically once weekly — not tested in any positive placebo-controlled trial.

The absence of a dosing standard is not a theoretical concern. It creates measurable, specific patient safety risks: patients receiving subtherapeutic doses may conclude ketamine is ineffective and abandon a treatment that might have worked at an appropriate dose; patients receiving doses with no controlled safety data face unknown risk. The research evidence that does exist — though heterogeneous and underpowered — points toward a convergent effective range that has never been compiled and made publicly accessible until now.