title: Severe neutropenia associated with sustained-release procainamide.
abstract: Neutropenia is a rare complication of procainamide therapy. However, over a period of 20 months, 8 patients developed severe neutropenia while taking a sustained-release preparation of the drug. Seven patients presented with fever and constitutional symptoms and one patient was asymptomatic. Bone marrow examinations showed myeloid aplasia or maturation arrest in 5 patients and myeloid hyperplasia in 1. Neutropenia resolved within 30 days of drug withdrawal, and all patients survived. A case-control study showed a significant association between sustained-release procainamide therapy and severe neutropenia in 5 of 114 patients (4.4%) recovering from open-heart surgery (Mantel-Haenszel chi square = 13.84; p less than 0.001). Thus, life-threatening neutropenia may be common with sustained-release procainamide preparations.
mesh_terms: D000368:Aged; D000380:Agranulocytosis / Q000139:chemically induced*; D001581:Benzothiadiazines; D006348:Cardiac Surgical Procedures; D003692:Delayed-Action Preparations; D004232:Diuretics; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000139:chemically induced*; D011183:Postoperative Complications; D011342:Procainamide / Q000009:adverse effects*; D049993:Sodium Chloride Symporter Inhibitors / Q000009:adverse effects
chemical_list: D001581:Benzothiadiazines; D003692:Delayed-Action Preparations; D004232:Diuretics; D049993:Sodium Chloride Symporter Inhibitors; D011342:Procainamide