How much secobarbital is too much and lethal?

LD-50=125 mg/kg. In 1927, a man named j.W. Trevan attempted to find a way to estimate the relative poisoning potency of drugs and medicines. The ld-50 is the lethal dose for 50% of animals... Prescribing information from lilly indicates a fatal blood level for secobarbitol sodium is between 15-40 micrograms/ml and the ld50 is 125 mg/kg. Stay far away from that dose!