Cromolyn sodium and theophylline in chronic perennial asthma.
D001249:Asthma / Q000188:drug therapy*; D004205:Cromolyn Sodium / Q000627:therapeutic use*; D006801:Humans; D013806:Theophylline / Q000627:therapeutic use*
D013806:Theophylline; D004205:Cromolyn Sodium