Ketamine for Depression, 4: In What Dose, at What Rate, by What Route, for How Long, and at What Frequency?

Summary & key facts

Researchers reviewed many studies on ketamine for depression and found that we still do not have firm answers about the best dose, how fast to give it, which way to give it, how long to treat, or how often to give treatments. Most studies used 0.5 mg/kg given over about 40 minutes, but effective doses reported ranged from 0.1 to 0.75 mg/kg and infusion times ranged from 2 to 100 minutes. Ketamine has been given safely and with some benefit by many routes (intravenous, intramuscular, subcutaneous, intranasal, oral, sublingual, and transmucosal), and treatment plans vary from a single session to repeated sessions over weeks, months, or even years in some hard-to-treat cases. The review says mo

Key facts:

• The dose most commonly used in studies was 0.5 mg/kg of ketamine.
• Some patients in studies responded to doses as low as 0.1 mg/kg, while others needed up to 0.75 mg/kg.
• The usual infusion time reported is 40 minutes, but sessions in studies have ranged from 2 minutes to 100 minutes.
• Intravenous administration is the most common route, but safety and benefit have also been reported with intramuscular, subcutaneous, intranasal, oral, sublingual, and transmucosal routes.
• Bolus (single-shot) dosing has been described as safe and effective when ketamine is given intramuscularly or subcutaneously.
• Patients in studies have received a single ketamine session or a course of sessions; in some refractory cases treatment has been continued for weeks to years.
• The authors conclude that dose, infusion rate, route, session length, and frequency likely interact in complex ways, so firm clinical recommendations are not currently possible.
• The review specifically says subcutaneous, intranasal, and oral ketamine deserve further study, and notes that home-based treatment would carry a risk of abuse.

Abstract

There is likely to be a complex interaction between ketamine dose, session duration, route of administration, frequency of administration, and related practice. Until definitive studies comparing different doses, rates of administration, routes of administration, and other considerations are conducted, firm recommendations are not possible. From the point of view of clinical practicability, subcutaneous, intranasal, and oral ketamine warrant further study. If domiciliary treatment is considered, the risk of abuse must be kept in mind.

Topics

Anesthesia and Sedative Agents Electroconvulsive Therapy Studies Treatment of Major Depression

Categories

Health Sciences Medicine Pharmacology

Tags

Amygdala Anesthesia Astrobiology Dosing Internal medicine Ketamine Major depressive disorder Medicine Nasal administration Pharmacology Physics Refractory (planetary science) Route of administration Treatment-resistant depression