<prompt> Methotrexate toxicity is treated by?Folinic acidFolic acidVitamin B 12Folinic acidVitamin B 12  <response>: Ans. is a i.e., Folinic acid Folinic acid rescue o Where it is desired to maximise the effect of methotrexate a potentially fatal dose is given and is followed 24 h later by a dose of folinic acid to terminate its action. o High concentrations of methotrexate are obtained and bone marrow cells recover better than the tumor cells and some degree of useful selectivity is achieved 