Method for Treating Depression

A method for treating depression in patients with depression and bipolar disorder who have not responded to antidepressants and to avoid dose dumping upon ingestion of alcohol, said method comprising orally administering an oral dosage form to a subject in need of such treatment, said oral dosage form comprising ketamine or a pharmaceutically acceptable salt or solvate thereof, wherein the dosage form provides an in vitro release of ketamine, when measured according to the USP Basket Method I in 0.1M HCl at 37° C. at 100 rpm, of 0 to 40% after 2 hours, of 10 to 70% after 4 hours, of 30 to 85% after 6 hours and of 45 to 100% after 8 hours,

• wherein the dosage form provides an in vitro release of ketamine, when measured according to the USP 1 Basket Method in 0.1M HCl at 100 rpm, after one hour at 37° C., in an aqueous solution containing 20% by volume of ethanol, in a ratio of less than 2:1 relative to the amount of ketamine released, so measured, after one hour at 37° C. in an ethanol-free aqueous solution,
• wherein the dosage form is a multi-particulate controlled release dosage form, wherein the dosage form comprises pellets containing a core comprising ketamine or a pharmaceutically acceptable salt or solvate thereof, and a release control layer comprising a release control substance coated upon the core, wherein the release control substance is a water insoluble polymer, and
• wherein the pellets are contained in an external phase of at least one pharmaceutically acceptable excipient.