Background. Impaired drug absorption is one of the reasons of the ineffectiveness of tuberculosis (TB) treatment. Malabsorption syndrome (MS) is a clinical syndrome that occurs due to the impaired digestive and transport function of the small intestine and is characterized by impaired absorption of nutrients, vitamins, microelements and drugs from the digestive tract. MS accompanies the following pathological conditions: pancreatic diseases, cholestasis, inflammatory bowel diseases, autoimmune enteropathies, diabetes mellitus, amyloidosis, hyperthyroidism, atrophic gastritis, HIV/AIDS, infections and parasitosis of the digestive system, alcoholism, and TB. Objective. To describe the ways to overcome the influence of MS on TB treatment. Materials and methods. Analysis of literature data on this topic. Results and discussion. MS can worsen the treatment of all forms of TB, especially severe. The latter include tuberculous meningitis, disseminated TB, miliary TB, caseous pneumonia, and infiltrative TB. Causes of death from severe forms of TB include untimely diagnosis, lack of thorough differential diagnosis, insufficient intensity of therapy, decreased maximum concentration of oral forms of anti-TB drugs (ATBD) in blood. The latter often occurs in severe forms of TB and in case of co-infection with TB and HIV/AIDS. Injectable forms of the drugs are recommended by the World Health Organization to increase the effectiveness of TB meningitis treatment. The American Thoracic Society and the American Society of Infectious Diseases also recommend the use of intravenous ATBD in patients with impaired absorption. Most patients receiving oral ATBD have extremely low plasma concentrations of these drugs. This is probably due to a decrease in the functional area of intestinal absorption in patients with TB. Indications for intravenous ATBD include severe forms of TB, the presence of severe disorders of the digestive system and severe comorbidities, TB with multiple and widespread resistance to ATBD, pre- and postoperative periods, low adherence to therapy. The intensive phase of therapy and the patient’s preference may be the additional indications. Studies show that intravenous ATBD is associated with significantly better survival than oral, in the absence of an increase in the number of side effects. The advantages of intravenous administration also include 100 % bioavailability, 100 % controllability of treatment, intensification of therapy, overcoming and preventing the development of resistance of mycobacteria, reducing the risk of adverse reactions, improving the tolerability of chemotherapy. Conclusions. 1. Impaired drug absorption is one of the reasons for the ineffectiveness of TB treatment. 2. MS can worsen the treatment of all forms of TB, especially severe. 3. In patients with malabsorption it is recommended to use intravenous ATBD. 4. Intravenous ATBD is associated with significantly better survival than oral, in the absence of an increase in the number of side effects.