Described herein are pharmaceutical formulations, methods for their production, and uses thereof. The pharmaceutical formulations comprise a salt of an optionally substituted dimethyltryptamine compound, a buffer, which is separate to the salt, and water. The formulations have pH values of from about 3.5 to about 6.5 and osmolalities of about 250 to about 350 mOsm/Kg. Such formulations are suitable for injection, being both stable and clinically acceptable, and have potential uses in the treatment of psychiatric or neurological disorders.