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A new episode of urticaria and/or angioedema can be an anxiety-inducing event for both the patient and the physician(s) seeing them in primary care, urgent care, or the emergency department. These events are commonly mistaken for "allergic" reactions and often mistreated. The most common causes of new onset urticaria in older children and adults, with or without angioedema, and normal vital signs or hypertension, are post-infection or acute idiopathic urticaria. These patients are not helped by systemic steroids, which may cause morbidity. An IgE-mediated allergy is almost never the cause. These episodes are easy to manage and virtually never life-threatening. Acute idiopathic urticaria is treated with high-dose nonsedating antihistamines acute avoidance of alcohol and nonsteroidal anti-inflammatory drugs, and time. An epinephrine prescription is not indicated for onset acute urticaria or angioedema, unless there is a strong suspicion of anaphylaxis, and they have been acutely treated with epinephrine. When anaphylaxis is suspected, because of hypotension or hypoxia, the treatment of choice is intramuscular epinephrine and supportive care. An acute tryptase then needs to be obtained within 1 to 3 hours of symptom onset, prior to a referral to Allergy. Most angioedema, without itching or hives, is idiopathic. Treatment is supportive care and time. Antihistamines, epinephrine, and systemic corticosteroids are completely ineffective in treating idiopathic or bradykinin-mediated angioedema. Suspect hereditary or acquired angioedema if there is recurrent non-itchy swelling with abdominal pain triggered by mechanical trauma. Only check a C4 prior to a referral to Allergy for a formal diagnosis and long-term management.

Rhinitis and related problems such as facial pressure and nasal congestion are a very common reason people seek medical care. There are four, often overlapping, syndromes or conditions that account for most of what patients perceive as "nose" problems or rhinitis. These conditions are irritant rhinitis, the anterior nasal valve effect, migraine with vasomotor symptoms, and allergic rhinitis. Virtually all patients with allergic rhinitis have some concomitant irritant or nonallergic rhinitis. Many migraine sufferers with vasomotor nasal symptoms will have their nasal congestion, headaches, and runny noses exacerbated by irritant rhinitis, allergic rhinitis, and/or a preexisting nasal valve effect. Failure to consider all of the causes for the symptoms will result in poor clinical outcomes. The work-up and management of these common conditions is discussed in this article.

Background: There is little prospective data on the antibiotics prescribed and the adverse reactions associated with their use after penicillin skin testing., Objective: Provide data on antibiotic use and new antibiotic "allergy" incidence after penicillin skin testing., Methods: All patients who had penicillin skin testing at our Medical Center between 1-1-2000 and 12-31-2004 were followed through 12-31-2009. All therapeutic antibiotic use and all new "allergies" listed in their electronic medical records were reviewed., Results: There were 1684 study subjects of whom 1191 (70.7%) were female. There were 118 (7.0%) positive to at least one penicillin skin test reagent and 3 (0.2%) were positive only to amoxicillin. The mean follow-up period was 4.5 ± 2.9 years. Subjects were exposed to a mean of 8.2 ± 10.5 therapeutic antibiotic courses during follow-up. The highest new antibiotic "allergy" incidence rates in skin test-negative subjects were noted for penicillins, 2.9%, and sulfonamides, 2.7%, p = 0.9097. Females had higher overall incidences of new antibiotic "allergy," independent of skin test result. Penicillin skin test-negative females treated with penicillin had a nonsignificantly higher new penicillin "allergy" incidence, 3.3% per course versus 1.9% for males, p = 0.0644. Cephalosporins had new antibiotic "allergy" incidence rates not significantly different from tetracyclines, quinolones, macrolides, clindamycin, metronidazole, nitrofurantoin, and other antibiotics., Conclusions: Females had higher new antibiotic "allergy" incidence rates. New "allergy" to cephalosporins occurred no more frequently than with non-beta-lactam-antibiotics, independent of skin test result. Sulfonamide antibiotics were associated with the higher rates of new antibiotic "allergy" than cephalosporins.

Background: Data on the rate of positive penicillin skin test (PenST) results over time in large populations are rare. The factors that influence positive PenST results are incompletely understood., Objectives: We sought to correlate demographic variables to the rate of positive PenST results over time in a large group of patients with a history of penicillin allergy., Methods: RESULTS from the first test for all patients tested for penicillin allergy in the Kaiser Permanente Health Care Program in San Diego County, CA, between 1995 and 2007 are reported. All patients were tested with penicillin, penicilloyl-poly-lysine, penilloate, penicilloate, and amoxicillin., Results: There were 255 positive PenST results in 3469 individuals. The rate of positive PenST results declined from >10% to <5% during the 13 years studied. The positive PenST result rate could be accounted for by the year of testing (R(2) = 0.56; p = 0.003) without any significant contribution from the patient's age or the time since reaction (TSR). If the TSR was ≤13 years, the relative risk of a positive PenST result was 2.1 (95% confidence interval = 1.6-2.8). If the study subject's age was ≤38 years, the relative risk of a positive PenST result was 2.1 (95% confidence interval = 1.6-2.7). Females reported higher rates of penicillin allergy history than males did (11% compared with 6.6%; p < 0.0001), but there were no significant sex differences in the rate of positive PenST results., Conclusions: There has been a steady decline in the proportion of positive PenST results between 1995 and 2007, independent of study subject age and TSR. Increasing age and increasing TSR were associated with a lower rate of positive PenST results.

Background: The major penicillin skin test reagent, penicilloyl-polylysine, has not been commercially available since October 2004. The minimal concentration of penicilloyl-polylysine necessary for safe penicillin skin testing has not been determined., Methods: Penicillin skin testing was performed on 596 individuals between October 2004 and October 2006 using out-of-date commercially produced penicilloyl-polylysine as part of a complete panel of reagents. The concentration of active penicilloyl-polylysine was measured. Outcomes were compared with those for 921 individuals tested between October 2002 and September 2004 using in-date commercially produced penicilloyl-polylysine., Results: There was no significant difference in the fraction of patients who had positive skin test results using indate (5.1%) versus out-of-date (4.7%) penicilloyl-polylysine. There were four mild but no serious adverse reactions in the patients tested with the outdated reagent who were then challenged with oral penicillin class antibiotics., Conclusion: Penicillin skin testing can be safely done using penicilloyl-polylysine down to a concentration of 4.29 × 10(-5) M.

Background: In selected inpatient settings, penicillin skin testing has been shown to affect antibiotic use. Routine penicillin skin testing has not been studied in hospitalized patients with a history of penicillin allergy., Objectives: To determine whether routine penicillin skin testing at a large regional hospital affected antibiotic use and/or antibiotic side effects in hospitalized persons with a history of penicillin allergy., Methods: A convenience sample of patients was penicillin skin tested from among those who had a history of penicillin allergy during any hospitalization from September 2002 through February 2003. Discharge coding was used to identify two age- and sex-matched control patients who had a history of penicillin allergy but who did not receive skin testing while hospitalized. All inpatient and outpatient antibiotic use, positive results of bacteriology culture obtained at any time from August 2002 through March 2003, and coded adverse reactions to medications were identified., Results: Of the 13,172 patients admitted to the hospital during the study period, 1627 (12.35%) had a history of penicillin allergy; of these 1627 patients, 141 (8.7%) received skin testing. Use of antibiotic agents was common: 79.4% of all study subjects received at least one antibiotic agent. Penicillins were used in substantially more cases than controls. Cephalosporins were the most widely used class of antibiotic agents, accounting for 26.8% of all antibiotic courses used. Of the six antibiotic-associated adverse drug reactions in five (1.2%) of the study subjects, one adverse reaction was associated with a penicillin, and one was associated with a cephalosporin., Conclusions: Routine penicillin skin testing in hospitalized patients is safe and allows more appropriate antibiotic use. To ensure that accurate information is available to support clinical care, hospitals should maintain a single centralized system for collecting data on drug allergy and testing.