Thirty elderly patients suffering from macrocytic anaemia associated with chronic diseases were treated with folinic acid for 25 days at a dosage of 4-8 mg daily. For each patient routine laboratory tests have been carried out, the clinical parameters have been recorded at the beginning and at the end of the trial and after 8 days of treatment a possible reticulocyte crisis has been evaluated. The results showed a significant decrease of medium corpuscular volume (MCV), of mean corpuscular haemoglobin (MCH), of iron as well as an increase of folic acid in the serum. After 8 days of treatment a statistically significant reticulocyte crisis was observed.