The Section on Urticaria and Angioedema Mentions Case Reports Vitamin C and Exercise-induced Bronchocon- Striction in Athletes

on the use of omalizumab in idiopathic angioedema. 2 We published 3 earlier case reports on the efficacy of omalizumab in intractable chronic urticaria. 3 We reported on 3 patients with refractory chronic urticaria who had marked improvement with omalizumab. Two of the patients showed evidence of increased anti-FceRI antibody levels, and 1 did not. We postulated that the possible mechanisms included the downregulation of IgE receptors, providing fewer targets for IgE or anti-FceRI antibodies. All our patients were started on injections every 2 weeks (based on weight and IgE level) but are currently still doing well with increasing the intervals between injections to every 4 weeks. We have also started 2 additional patients on omalizumab, with similar significant clearing of urticaria within 1 week. Successful treatment of urticaria with anti-IgE therapy has also been reported by other authors. 4,5 Omalizumab appears to be a very promising therapeutic alternative for refractory urticaria and angioedema. Successful treatment of cold-induced urticaria/anaphylaxis with anti-IgE. To the Editor: Anderson and Kippelen 1 reviewed the mechanisms of and therapeutic approaches to exercise-induced bronchoconstriction (EIB) in athletes. In addition to the treatments they discussed, vitamin C can also affect EIB. We carried out a systematic review of the effect of vitamin C supplementation on the common cold. 2,3 Vitamin C consistently reduced the duration of common cold symptoms, but the effect on common cold incidence was significantly heterogeneous. In the general population, vitamin C supplementation had no preventive effect; however, the supplements halved the incidence of colds in 6 placebo-controlled trials with participants under heavy acute physical stress: pooled relative risk, 0.50 (95% CI, 0.38-0.66; total, n 5 642). Four of these trials were with marathon runners, 1 was with Canadian soldiers in a northern training exercise, and 1 was with schoolchildren in a skiing camp in the Swiss Alps. In the general community the acute symptoms of cough, sore throat, and runny nose usually have a viral cause. However, it is not obvious that similar symptoms occurring after a marathon run are caused by a viral infection because they can result from an injury to runners' airways caused by their hours of exceptional ventilatory exertion. 1 Thus the common cold studies of marathon runners might have been measuring, at least in part, the effects of vitamin C on the physical injury to their airways instead of viral infections. In their trial with marathon runners, Peters …