The assessment of the biological age is needed to estimate the level of health and the efficacy of measures being undertaken to slow down the ageing processes and prolong the active life of the patients. Earlier studies have demonstrated the improvement of both physical health and psychic status of the elderly patients following intravenous administration of procaine. The objective of the present work was to evaluate effect of various methods of administration of a 2% procaine solution on the biological age. A total of 95 subjects at the age between 30 and 75 years were enrolled in the study. The procaine solutions were applied to the collar region. The patients of group 1 were treated with 2% procaine electrophoresis, those in group 2 with procaine galvanization with the same parameters. Mesotherapy using the 2% procaine solution was given to the patients of group 3. It was substituted by placebo (0.9% physiological solution) in the patients of group 4 (controls). The study revealed the most significant decrease of the biological age (calculated as described by L.M. Belozerova) in the patients treated with procaine electrophoresis (91% improvement). The mesotherapeutic administration of procaine also produced the beneficial effect (59% improvement). Neither procaine galvanization nor placebo mesotherapy caused any significant change of the variables characterizing the biological age.