Talc pleurodesis is an effective technique for the management of symptomatic malignant pleural effusions. It is assumed that a good dispersion of talc suspension contributes to the final success of this treatment. For this purpose, guidelines often advise to rotate the patient after intra-pleural instillation of the sclerosant. This prospective, randomized study analyses the dispersion of talc suspension and the overall success rate in patients with malignant effusions. After instillation of 99mTc-sestamibi-labeled talc suspension ten subjects were rotated for 1 h, while the ten other patients remained in a stable supine body position. Scintigraphic imaging was done in two directions immediately after instillation and after 1 h with a clamped drain. The overall success of the treatment was assessed 1 month after the pleurodesis. The dispersion of talc was limited and unequal in 75% of the subjects. In two patients with apparently good distribution on anterior views, the lateral views of the scintigraphy showed only limited distribution. Rotation of the patients did not influence the dispersion of sludge after 1 min or 1 h. Pleurodesis was successful in 85% of the patients after 1-month follow-up. Standard rotation protocols for patients with malignant pleural effusion do not affect the overall dispersion of talc suspension and should be abolished because of the discomfort caused to the patients.