Methods, formulations and kits for treating and/or protecting against acute liver failure and other hepatotoxicities in an individual employ a combination of a first active agent which replenishes, or decreases a loss of, functional glutathione in the individual, and a second active agent comprising a manganese complex selected from the group consisting of (i) a calcium manganese mixed metal complex of N,N′-bis-(pyridoxal-5-phosphate)-ethylenediamine-N,N′-diacetic acid (DPDP) having a molar ratio of calcium to manganese in a range of from 1 to 10, or a pharmaceutically acceptable salt thereof, (ii) a mixture of manganese DPDP (MnDPDP), or a pharmaceutically acceptable salt thereof, and a non-manganese-containing DPDP compound, or (iii) a mixture of manganese pyridoxyl ethylenediamine (MnPLED), or a pharmaceutically acceptable salt thereof, and a non-manganese-containing pyridoxyl ethylenediamine (PLED) compound.