Abstract: The invention refers to a lipid carrier composition for controlled release of a bioactive substance, which comprises at least one triglyceride oil, and at least one polar lipid selected from the group consisting of phosphatidylethanolamine and monohexosylceramide, and ethanol, which is characterised in that the carrier composition has the ability to form a cohesive structure, which structure is retained in an aqueous environment. The invention also refers to a pharmaceutical composition consisting of said lipid carrier and a bioactive substance dissolved or dispersed in the carrier, preferably an injectable composition.