The invention relates to the field of medicine, and more particularly to pharmacology, and even more particularly to pharmaceutical compositions for treating various conditions associated with a lack of energy potential resulting from a pathological process. A pharmaceutical composition for correcting symptoms of or treating asthenia and/or chronic fatigue syndrome, when isolated or combined with various diseases and/or premorbid and/or postmorbid conditions in mammals, is characterized in that it contains, as active ingredients, 2-ethylthiobenzimidazole hydrobromide and/or a pharmaceutically acceptable salt thereof, and levocarnitine in therapeutically effective amounts.