Additive benefits of EFAs in dogs with atopic dermatitis after partial response to antihistamine therapy.

It has been reported that 20 to 70 per cent of atopic cases in the dog can be controlled with antihistamines, though the effective antihistamine cannot be predetermined. Combination therapy with essential fatty acids (EFAs) and antihistamines has been shown to be useful in dogs. All of the work published to date has been performed in open studies, without the use of placebo, and in dogs where the aim has been to control pruritus as a symptom rather than that caused specifically by atopy. The aim of this study was to assess the combined effects of four antihistamines; hydroxyzine, chlorpheniramine, cyproheptadine and clemastine; with both an EFA supplement and a placebo of olive oil, in 25 dogs to control pruritus in clinically proven cses of atopy.

Multicenter, crossover study of the efficacy and tolerability of terfenadine, 120 mg, versus cetirizine, 10 mg, in perennial allergic rhinitis.

In this 3-week randomized, double-blind, double-dummy multicenter, crossover study terfenadine, 120 mg, was compared with cetirizine, 10 mg, both given once daily in the treatment of perennial allergic rhinitis in sixty patients. Compared with the investigators' pretreatment assessment, both terfenadine and cetirizine significantly reduced the severity of all five symptoms (P less than .001). The two treatments were equally effective in controlling eye irritation, sneezing, nasal congestion and itchy nose, throat and palate, but cetirizine improved rhinorrhea more than terfenadine (P less than .05). Daily symptom assessments by the patients for the last 14 days of each treatment period showed no difference in efficacy between the two drugs for any of the symptoms. There were also no differences between the two drugs for overall assessments of efficacy or patient preference. Adverse events were recorded more frequently while taking cetirizine, with 14 attributable events compared with only five with terfenadine. Four of the cetirizine-related events were drowsiness or tiredness, but none was reported while patients were taking terfenadine. There was a tendency to increased weight (greater than 1 kg) with both treatments.

Controlled trial of H1 antagonists in the treatment of chronic idiopathic urticaria.

The efficacy of astemizole, diphenhydramine, and hydroxyzine hydrochloride in the treatment of chronic idiopathic urticaria was evaluated in this 3-month double-blind, randomized, parallel group study. Thirty-six adult patients were randomly assigned, 13 to the astemizole group (10 mg daily), 12 to the diphenhydramine group (25 mg t.i.d.), and 11 to the hydroxyzine hydrochloride group (25 mg t.i.d.). Demographic data were statistically similar for all variables assessed in the three treatment groups. Seven (58%) of the diphenhydramine patients withdrew before the end of the study, six because of lack of efficacy and one because of drowsiness. Two (18%) of the hydroxyzine hydrochloride patients withdrew, one because of lack of efficacy and one because of drowsiness. Two patients (15%) in the astemizole group withdrew, one because of adverse reaction, and the other because of lack of efficacy. Mean total symptom scores and mean individual symptom scores were lower in the astemizole group than in the other two groups. Wheal area measurements (0.1 mg/mL histamine challenge) decreased more in the astemizole and hydroxyzine hydrochloride groups than in the diphenhydramie group (P = .02). With regard to symptoms, 12/13 patients in the astemizole group improved clinically during their treatment period, versus 8/11 in the hydroxyzine hydrochloride group and 5/12 in the diphenhydramine group. The mean time to first observed therapeutic effect (maintained for three consecutive days) was 5.5 days in the astemizole group, 10.9 days in the hydroxyzine hydrochloride group, and 7.2 days in the diphenhydramine group. In this study, astemizole was as effective as hydroxyzine in patients treated for chronic idiopathic urticaria.

Double-blind comparison of cetirizine and placebo in the treatment of seasonal rhinitis.

The efficacy and safety of cetirizine were evaluated in 419 patients with seasonal allergic rhinitis. Using a 4-way, double-blind randomization schedule, patients were given a 1-week course of once daily cetirizine (5, 10, or 20 mg) or placebo. Patient and physician efficacy ratings corresponded, indicating superiority of cetirizine to placebo (P less than .05) in reducing symptom severity scores for sneezing, rhinorrhea, ocular pruritus, nasal pruritus, watering of the eyes, and redness of the eyes. All cetirizine doses achieved higher efficacy ratings (72.7%, 79.2%, and 75.7%, respectively) than placebo (52.9%; P less than .05) by the physician's global assessment. Cetirizine was well tolerated, with sedation being the most common adverse experience, increasing in frequency at higher doses. A dose-response relationship was evident for selected symptoms, and the once daily 5-mg dose was found to be an effective minimum dose.

Physicochemical stability of a preanesthetic mixture of hydroxyzine hydrochloride and atropine sulfate.

The stability of a combination of hydroxyzine hydrochloride and atropine sulfate stored in syringes was studied. Syringes containing the two drugs were stored at 25 C and 3 C for ten days and analyzed at specific time intervals. Absorption spectra, chromatographic characteristics and pH were determined. Results showed the admixture to be stable for ten days at room temperature or under refrigeration. The technique used would probably not detect any significant degradation of atropine sulfate unless the reaction occurred with the hydroxyzine hydrochloride.