The neuromuscular junction rest method was employed in the treatment of 18 myasthenic and cholinergic crisis occurring in 12 patients with severe forms of myasthenia gravis. Six of these patients received a "relative rest" and other six patients received an "absolute rest" treatment. In the first group of patients the method consisted essentially in withdrawal of anticholinesterase therapy and mechanical respiratory support with early performance of traqueostomy and use of the intermitente positive pressure breathing (I.P.P.B.) with cuffed traqueostomy tube. The patients of second group, in addition to this management, were submitted to prolonged curarization by galamine (Flaxedil by intramuscular injection); all of them presented an initial curare supersensitivity which always decreased shortly. In both methods the reinstitution of the drug therapy was progressive. The respirator weanned of progressively and the patients were kept under observation for adequate ventilation. The doses were variable but subsequent doses of antimyasthenic medications were determined by clinical findings and response to the tensilon or prostigmine tests. The doses were increased or decreased accordingly in each individual case, rapid changes of drug doses to perfect adjustment being undesirable in this transition period. Partial or temporary remission occurred in some patients. Others were able to sustain satisfactory ventilation for a long period or definitively. Most of the crisis improved and most of the patients benefited from the therapeutic method of the neuromuscular junction rest. There was a remarkable reduction in the mortality rate from the crisis. One patient had a thymoma which was malignant; in spite of this the evolution of this case has been good after the treatment. Those patients who had immediate good response to the treatment of the crisis had a favorable fellow up, even a complete remission. Respiratory infections were very common in spite of all cares. Culture of tracheal secretions and wound exsudates were made. Bactericidal and broad-spectrum antibiotics were used, depending of the laboratory report cf patient's sensitivity. Physiotherapy besides other prophylactic measures was used against bronchopneumonia. Atelectasis was a common complication in the crisis and all efforts to prevent it were made, including daily clinical examination of pulmonary conditions, Vt,, blood pressure and bed side chest films. The routine use of atropine sulfate promoved inspissation of bronchial secretions, plugging of the bronchi, and attendant atelectasis, infection and bronchopneumonia. Exceptionally, steroids or bronchoscopy had been used.