To study the causes of resistant pleural effusions and efficiency of chemical pleurodesis with Betadin, Iodopyrone and concentrated glucose solution in these patients. Resistant pleuritis with daily exudation over 300 ml lasting ≥6 days occurred in 206 (48%) out of 424 cases of pleural effusions. Twenty-seven patients underwent chemical pleurodesis with Betadine, 15 patients - mixture of Iodopyrone with concentrated glucose solution. Solutions were injected via pleural drainage. In multivariate analysis, the risk factors of complicated pleuritis were air leakage, prolonged drainage period, age over 60 years, fluid output volume during thoracoscopy and higher Charlson index. Pleurodesis with a mixture of Betadine 10% 10 ml and glucose 40% 40 ml suppressed exudation in 92.6% of cases. Pleurodesis with a mixture of Iodopyron and glucose solution in the same quantities was effective in 93.4% of cases. If exudation continued, pleurodesis was repeated after 3 days. VAS score of pain syndrome following Iodopyrone injection was 3.0±1.8, in case of Betadine - 3.4±0.3. No significant hemodynamic changes were noted. In case of malignant pleural effusions and low functional parameters after fluid evacuation, favorable effect was obtained after pleurodesis with a mixture of povidone-iodine with glucose through the same catheter and subsequent removal of drainage tube. Resistant pleural effusions with daily exudation over 300 ml for more than 6 days are characterized by advanced risk of infectious and inflammatory complications due to air leakage and duration of drainage. Pleurodesis with mixtures of Betadine or iodopyrone and 40% glucose solution is effective for resistant pleural effusions.