Ketamine Tablets vs IV Infusion

Ketamine tablets and IV infusion are the two main ways patients receive ketamine for treatment-resistant depression, and the right choice depends on how fast you need relief, your budget, and how much clinical supervision you want. IV infusion delivers ketamine directly into the bloodstream in a clinic setting, giving 100% bioavailability and the fastest, most intense response. Ketamine tablets are taken orally at home under a treatment monitor's guidance, offering lower cost and more flexible dosing, but a slower onset and a different pharmacological profile due to first-pass liver metabolism. This guide compares ketamine tablets vs IV infusion across bioavailability, cost, efficacy, and access, and outlines when clinicians combine both routes in a single treatment plan.

Pharmacological Differences

Bioavailability and Metabolism

IV infusion delivers 100% bioavailability. Every milligram administered reaches the bloodstream as unchanged ketamine, with no first-pass metabolism. Ketamine tablets have only 10-25% bioavailability because the liver processes most of the dose before it reaches systemic circulation. According to StatPearls, oral ketamine undergoes extensive first-pass hepatic metabolism that converts 75-90% of the dose to norketamine, an active metabolite with its own effects, before the drug reaches the bloodstream. Learn more about how this metabolite shapes the tablet experience in our norketamine and tablet effects guide, and see the underlying pharmacokinetic data in our bioavailability studies review. In practice, a 2.0 mg/kg oral dose delivers roughly the same amount of active ketamine as a 0.2-0.5 mg/kg IV dose.

Onset and Duration

IV infusion effects begin within 1-5 minutes, with peak dissociation occurring during the 40-minute infusion. Effects substantially resolve within 1-2 hours after the infusion ends. Ketamine tablets begin working in 30-60 minutes, peak at 1-2 hours, and last 3-5 hours total because of slower absorption and longer norketamine exposure. For a full breakdown of the research behind these timelines, see our oral vs. IV comparative research article.

Subjective Experience

IV infusion at the standard 0.5 mg/kg dose produces intense, immersive dissociation. Many patients describe profound perceptual changes, emotional experiences, or dream-like states. The experience is powerful and can be either transformative or uncomfortable depending on the patient. Ketamine tablets produce gentler, more gradual effects, with mild to moderate dissociation at typical therapeutic doses. Most patients remain oriented and conversational, though judgment is impaired. Patients and clinicians generally describe the tablet experience as more manageable.

Clinical Comparison

Efficacy

IV ketamine has the larger evidence base. Multiple large randomized controlled trials show response rates of 60-70% in treatment-resistant depression within 24 hours of a single infusion, and the acute effect is well documented. The National Institute of Mental Health describes treatment-resistant depression as depression that does not respond adequately to standard antidepressant trials, which is part of why rapid-acting options like ketamine draw clinical interest. Ketamine tablets have a smaller evidence base but consistently positive results, with response rates of 50-77% in treatment-resistant depression over 1-4 weeks of repeated dosing. Per session, the tablet effect is typically smaller than IV, but cumulative repeated dosing can produce comparable sustained outcomes.

Setting and Supervision

IV infusion requires an infusion clinic with trained nursing staff, cardiac monitoring, IV access, and emergency protocols, and the patient must travel to the clinic for every session. Ketamine tablets, typically sourced from a compounding pharmacy, can be taken at home with a treatment monitor present and require no clinical infrastructure beyond a prescriber and pharmacy. Blood pressure monitoring at home is recommended but not technically complex.

Cost

IV infusion costs $400-$800 per session, and a standard 6-infusion induction course runs $2,400-$4,800, with maintenance infusions adding ongoing cost. IV is rarely covered by insurance for psychiatric indications. Ketamine tablets cost $8-$30 per dose from compounding pharmacies, with monthly costs of $200-$600 including clinical oversight, or $130-$400 per month through bundled telehealth services. Tablets are substantially more affordable per month of treatment. See our guide to the insurance coverage gap for oral ketamine for what to expect from your plan.

Access

IV infusion access is limited by clinic availability, geography, and scheduling, and patients in rural areas may have no local infusion clinic. Each session requires travel time, 2-3 hours of clinic time including monitoring, and a driver home. Ketamine tablets are available anywhere a prescriber can write a prescription and a compounding pharmacy can ship, and telehealth has made this accessible to nearly any location. Dosing at home eliminates the travel burden.

Frequency

IV acute induction typically involves 6 infusions over 2-3 weeks, with maintenance at 1 infusion every 2-8 weeks; frequency is limited by practical and financial constraints. Ketamine tablets can be taken 2-3 times weekly during acute treatment, tapering to weekly or biweekly for maintenance, giving more flexibility to adjust frequency.

When IV Infusion Is the Better Choice

• Acute severe depressive episodes requiring a rapid response
• Active suicidal ideation requiring the fastest possible intervention
• Initial treatment induction when a strong first response is the priority
• Patients who have not responded to an adequate trial of oral ketamine
• Clinical situations where supervised administration is essential

When Tablets Are the Better Choice

• Long-term maintenance therapy after an initial response
• Geographic or financial barriers to IV clinic access
• Patients who find the IV experience too intense or distressing
• Chronic pain requiring frequent or daily dosing
• Patients with stable conditions appropriate for home-based treatment
• Continuation therapy between IV sessions

The Combined Approach

Many clinicians use a sequential strategy that combines both routes over the course of treatment:

• Induction (weeks 1-3): IV ketamine infusions, typically 4-6 sessions, to establish an acute response
• Transition (weeks 3-6): Overlapping IV and oral dosing as the patient shifts to tablets
• Maintenance (month 2 onward): Ketamine tablets at home, with the IV option available for breakthrough episodes

This approach combines the reliability and potency of IV for the acute phase with the practicality and affordability of tablets for the long term. Our review of ketamine tablets and treatment-resistant depression remission covers how patients maintain response once they transition to at-home dosing.

References

• StatPearls: Ketamine, comprehensive clinical reference on ketamine pharmacology, mechanisms of action, and therapeutic applications
• MedlinePlus: Ketamine, National Library of Medicine consumer drug information on ketamine including uses, proper administration, and precautions
• NIMH: Depression, National Institute of Mental Health overview of depressive disorders, treatment-resistant forms, and emerging therapies
• Mayo Clinic: Treatment-Resistant Depression, Mayo Clinic resource on treatment-resistant depression diagnosis, management, and emerging therapies