T-61 is a euthanasia solution to be used only on unconscious animals. Each mL of T-61 contains 200 mg Embutramide (which produces a strong narcotic action and concurrently paralyses the respiratory centre), 50 mg Mebezonium Iodide (which produces a curariform paralytic action on striated skeletal and respiratory muscles and rapidly induces circulatory collapse) and 5 mg Tetracaine Hydrochloride, in aqueous solution.