Part 1: Acute Urticaria/Angioedema

Risk of hospitalization for angio-oedema among users of newer COX-2 selective inhibitors and other nonsteroidal anti-inflammatory drugs

AIM

To examine the risk of angio-oedema among users of the newer cyclooxygenase (COX)-2 selective inhibitors celecoxib and rofecoxib and other non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs) in a population-based case-control study.

METHODS

Cases of angio-oedema were identified from hospital discharge registries from three Danish counties between 1 January 2000 and 31 December 2003 (n = 377) and 10 matched population controls per case were selected from the Civil Registration System (n = 3747). Data on newer COX-2 selective inhibitor and other NSAID use (current and former) were obtained from prescription databases. Data on potential confounding factors were also collected. Conditional logistic regression was used to compute relative risks for angio-oedema according to drug exposure.

RESULTS

The crude relative risks for the newer COX-2 selective inhibitors were higher than those for other NSAIDs. After adjustment for confounding, the relative risk for current use of newer COX-2 selective inhibitors was 0.96 [95% confidence interval (CI) 0.46, 2.03], whereas the risk for other NSAIDs was 1.77 (95% CI 1.23, 2.58).

CONCLUSION

Our data support the hypothesis that newer COX-2 selective inhibitors are safe in relation to angio-oedema. However, given other current health concerns related to these drugs, their use should continue to be carefully monitored.

Second-Generation Antihistamines

Antihistamines are useful medications for the treatment of a variety of allergic disorders. Second-generation antihistamines avidly and selectively bind to peripheral histamine H1 receptors and, consequently, provide gratifying relief of histamine-mediated symptoms in a majority of atopic patients. This tight receptor specificity additionally leads to few effects on other neuronal or hormonal systems, with the result that adverse effects associated with these medications, with the exception of noticeable sedation in about 10% of cetirizine-treated patients, resemble those of placebo overall. Similarly, serious adverse drug reactions and interactions are uncommon with these medicines. Therapeutic interchange to one of the available second-generation antihistamines is a reasonable approach to limiting an institutional formulary, and adoption of such a policy has proven capable of creating substantial cost savings. Differences in overall efficacy and safety between available second-generation antihistamines, when administered in equivalent dosages, are not large. However, among the antihistamines presently available, fexofenadine may offer the best overall balance of effectiveness and safety, and this agent is an appropriate selection for initial or switch therapy for most patients with mild or moderate allergic symptoms. Cetirizine is the most potent antihistamine available and has been subjected to more clinical study than any other. This agent is appropriate for patients proven unresponsive to other antihistamines and for those with the most severe symptoms who might benefit from antihistamine treatment of the highest potency that can be dose-titrated up to maximal intensity.