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D G Tinkelman

Publications and source records attributed to D G Tinkelman.

At least 19 recordsLinked to original sources
PubMed2001

Barriers to measuring and achieving optimal outcomes in pediatric asthma.

To measure the effectiveness of any therapeutic endeavor, a set of defined outcome measurements must be performed, or the task of determining the effectiveness of any therapeutic step becomes difficult. With asthma, however, in which case it is difficult to establish the initial diagnosis, beginning a program of outcome measurements regarding any therapeutic interaction is nearly impossible. Conventional means are thwarted at the outset. One way of approaching the problem of obtaining reproducible outcomes data is to examine those areas in which measurements can be made and determine the barriers to obtaining the data. Establishing a good medical history is a critical step that, in general, is especially difficult with very young children, and tools that provide objective measurements that are used in the normal evaluation of older children are of little use in the very young child with asthma. Parts of the physical examination are difficult to perform in very young children, and findings associated with asthma can be found in other clinical states. In this age group, diary keeping suffers from the same problems and issues that are related to obtaining an accurate medical history. Barriers also exist to obtaining the best outcomes. The choice of medications for the very young child is limited; there are several typical adherence problems, and information about adverse effects is limited.

Asthma↗
PubMed2000

Disease management program improves asthma outcomes.

OBJECTIVE: To show that a disease management program that empowers patients with asthma to participate in the management of their condition can improve quality of life and reduce the use of medical services. STUDY DESIGN: Utilization and quality-of-life data were tracked to identify outcome changes in patients with moderate to severe asthma. Baseline measures were used as a control and were compared with measures taken at 6 and 12 months after enrollment. PATIENTS AND METHODS: Study participants were from a single Medicaid managed care plan in western Pennsylvania. Patients' quality of life during their participation in the program was tracked through an outside pharmacoepidemiologic research firm. Utilization data were updated with every interaction between a patient and case management nurse. RESULTS: Both quality-of-life and utilization data show statistically significant improvements at 6 months. Further, 12-month data show improvement that is statistically significant in all measures with the exception of the adult quality-of-life measure, where a small sample size limited the statistical results. CONCLUSIONS: A collaborative, proactive approach to asthma management improves patients' quality of life and reduces use of costly medical services.

Adolescent↗
PubMed1998

Growth in asthmatic children treated with fluticasone propionate. Fluticasone Propionate Asthma Study Group.

OBJECTIVE: To determine whether inhaled fluticasone propionate has long-term effects on growth in children with persistent asthma. STUDY DESIGN: In a double-blind, randomized, parallel-group, multicenter study, 325 prepubescent children with persistent asthma and normal growth rates were treated with placebo or inhaled fluticasone propionate powder 50 microg or 100 microg administered twice daily by a breath-actuated device for 1 year. Growth was evaluated monthly, whereas other safety variables and pulmonary function were evaluated periodically. RESULTS: The prepubescent patients showed no statistically significant differences in mean height, mean growth velocity, or mean skeletal age between any of the treatment groups at any time. Over a period of 1 year, mean height (+/- SE) increased 6.15 +/- 0.17 cm in the placebo group, 5.94 +/- 0.16 cm in the fluticasone propionate 50 microg group, and 5.73 +/- 0.13 cm in the fluticasone propionate 100 microg group (p = 0.308, overall). CONCLUSIONS: Prepubescent children treated with fluticasone propionate 50 microg and 100 microg administered twice daily for 1 year grew at rates similar to placebo-treated control subjects and at rates equal to expected growth velocity for age.

Administration, Inhalation↗
PubMed1998

Aerosol beclomethasone dipropionate spray compared with theophylline as primary treatment for chronic mild-to-moderate asthma. The American Academy of Allergy, Asthma and Immunology Beclomethasone Dipropionate-Theophylline Study Group.

BACKGROUND: Inhaled corticosteroids and oral theophylline are effective treatments for moderate asthma. OBJECTIVE: We sought to compare the benefits and adverse reactions of theophylline and aerosol beclomethasone spray. METHODS: A multicenter, double-blind, double-placebo, randomized, controlled trial of 1-year duration was performed. Seven hundred forty-seven patients with asthma received either beclomethasone dipropionate aerosol spray (84 microg four times per day) or sustained-release theophylline twice per day in doses adjusted for optimum control of the disease. The main outcome measures were daily diary of symptoms and peak flow rates (recorded on a mark-sense computer-readable form); supplemental bronchodilator use; doctor's office or hospital visits and absence from work or school; spirometry; methacholine testing; adverse experiences; and cortisol blood measurements. RESULTS: Both treatment strategies reduced symptoms promptly and achieved low absenteeism from work or school and low rates of emergency treatment for asthma. Both maintained nearly normal pulmonary function. Beclomethasone was statistically significantly more effective in reducing symptoms, supplemental bronchodilator and systemic glucocorticoid doses, bronchial hyperresponsiveness, and eosinophilia. However, the magnitude of these differences was small. Theophylline caused more headache, nervousness, insomnia, and gastrointestinal distress, and more patients discontinued treatment because of side effects. Beclomethasone caused more oropharyngeal candidiases and hoarseness and reduced morning plasma cortisol levels before and after cosyntropin. It reduced the rate of growth in children. No new cataracts or glaucoma developed. CONCLUSION: Theophylline effectively controlled symptoms at lower than the customarily recommended blood level. The risk/ benefit profiles of these agents suggest that inhaled corticosteroids may be the preferred agent for most adult patients and for some children.

Adolescent↗
PubMed1998

A multicenter, placebo-controlled study of twice daily triamcinolone acetonide (800 microg per day) for the treatment of patients with mild-to-moderate asthma.

BACKGROUND: National and international guidelines recommend the use of inhaled antiinflammatory medications in patients with all but the mildest forms of asthma. Twice daily dosing may increase compliance with therapy. OBJECTIVE: We sought to evaluate the safety and efficacy of 400 microg twice daily triamcinolone acetonide (TAA) compared with placebo in adult patients with mild-to-moderate asthma who were poorly controlled by beta2-agonist therapy. METHODS: We performed a multicenter, randomized, double-blind, placebo-controlled study, including a screening visit, a 7- to 21-day pretreatment baseline phase, and a 6-week double-blind treatment phase. Efficacy was measured by weekly spirometry and daily diary recordings of peak flow rates, asthma symptom scores, and albuterol use. Eligible patients used albuterol four or more times per day, had total asthma symptom scores of 15 or greater (possible total, 60) over 5 of 7 baseline days, and had FEV1 measurements of 60% of predicted value or greater. RESULTS: One hundred twenty-one patients were randomized to treatment. TAA was superior to placebo for all efficacy measures, with significant improvements in asthma symptoms, albuterol use, morning and evening peak flow rates, and forced vital capacity evident at Treatment Week 1. Significant improvements in other pulmonary function measurements were observed after 2 or more weeks. All efficacy variables improved progressively throughout the study. CONCLUSIONS: Twice daily TAA (400 microg) decreased asthma symptoms and improved lung function in patients with mild-to-moderate asthma compared with placebo. Therapeutic benefit was evident within 1 week and increased throughout treatment.

Adult↗
PubMed1998

Proventil HFA provides bronchodilation comparable to ventolin over 12 weeks of regular use in asthmatics.

OBJECTIVE: To compare the bronchodilator effectiveness of albuterol reformulated in the chlorofluorocarbon-free propellant hydrofluoroalkane (HFA)134a (Proventil HFA) to that of Ventolin and HFA placebo over 12 weeks of regular dosing. DESIGN: Randomized, double-blind, double-dummy, parallel group, placebo-controlled, multi-center trial of asthmatics requiring inhaled beta-adrenergic bronchodilators for symptom control. INTERVENTIONS: Treatment qid with Proventil HFA, Ventolin, or HFA-134a placebo for 12 weeks. MEASUREMENTS: At weeks 0, 4, 8, and 12, spirometry was performed predose and serially over 6 h after dosing with study drug. Bronchodilator efficacy variables, based on FEV1 response to study drug, were proportion of responders, time to onset of effect, peak percent change, time to peak effect, duration of effect, and area under the curve (AUC). RESULTS: Demographic and baseline characteristics were similar for patients randomized to Proventil HFA (193), Ventolin (186), and HFA-134a placebo (186). No significant differences were found between the Proventil HFA and Ventolin treatment groups for any FEV1 efficacy variable, either predose or during 6 h of serial spirometry, at weeks 0, 4, 8, and 12. For all efficacy variables, except time to onset of effect, the Proventil HFA and Ventolin results were significantly greater than placebo. Time to onset of effect for the HFA-134a placebo group is misleading; only 13 patients (7%) were found to be responders in the intent-to-treat database. These efficacy results were found to be consistent across subgroup analyses of inhaled and nasal corticosteroid use, age (18 to 35 and 36 to 66 years), sex, race, weight (<60, 60 to 100, and >100 kg), and baseline FEV1 (< or =55% and >55% predicted). The peak FEV1 effect, duration of FEV1 effect, and AUC for FEV1 were all significantly smaller at weeks 4, 8, and 12 than week 0 for both the Proventil HFA and Ventolin treatment groups. CONCLUSIONS: Proventil HFA provided bronchodilation comparable to Ventolin and superior effects to HFA-134a placebo over 12 weeks of regular dosing. There was a diminution in bronchodilator response to both Proventil HFA and Ventolin after 4 weeks of use.

Administration, Inhalation↗
PubMed1998

Proventil HFA and ventolin have similar safety profiles during regular use.

OBJECTIVE: As a secondary objective to a long-term study evaluating the bronchodilator effectiveness of Proventil HFA (albuterol), to assess the safety of Proventil HFA, Ventolin, and hydrofluoroalkane 134a (HFA-134a) placebo over 12 weeks of regular dosing. DESIGN: Randomized, double-blind, double-dummy parallel group, placebo-controlled, multicenter trial of asthmatics requiring inhaled beta-adrenergic bronchodilators for symptom control. INTERVENTIONS: Treatment with Proventil HFA, Ventolin, or HFA-134a placebo, qid, for 12 weeks. MEASUREMENTS: Adverse events were reviewed at biweekly clinic visits. Between clinic visits, patients recorded morning and evening peak expiratory flow (PEF), asthma symptom and nighttime asthma sleep disturbance scores, and use of rescue beta-adrenergic bronchodilator on diary cards daily. Investigators provided a global assessment of asthma control at weeks 0, 4, 8, and 12. Vital signs were recorded over 6 h after dosing with study drug at weeks 0, 4, 8, and 12. Standard laboratory tests, CBC count, serum chemistries, and urinalysis were obtained at study start and end. RESULTS: Adverse event reporting rates were similar for the three treatment groups. The morning PEF tended to be lower for the Proventil HFA and Ventolin groups than the HFA-134a placebo group, but the evening PEF tended to be higher for the active treatment groups. Daytime asthma symptom scores tended to be lower (better) with active treatment than placebo, but nighttime asthma sleep disturbance scores were similar for all three treatment groups. Use of Ventolin Rotacaps as rescue medication was significantly greater for the HFA-134a placebo group than the Proventil HFA and Ventolin groups. Diary card data did not change within groups over time. Investigator global assessments of asthma scores clustered between fair and good for all three treatment groups throughout the study. Changes in heart rate and BP were small after dosing with study drug and tended to be similar for the active treatments and HFA-134a placebo groups. No clinically meaningful changes in results of standard laboratory tests were found in any treatment group during this study. CONCLUSIONS: Proventil HFA had a similar safety profile as Ventolin during regular use. A dosage of 16 puffs per day of propellant HFA-134a was well tolerated by asthmatics. Regular use of either Proventil HFA or Ventolin did not cause asthma control to deteriorate.

Administration, Inhalation↗
PubMed1997

Use of an anti-IgE humanized monoclonal antibody in ragweed-induced allergic rhinitis.

BACKGROUND: Increased serum levels of antigen-specific IgE are often associated with allergic respiratory disorders. RhuMAb-E25, a recombinant humanized monoclonal antibody, decreases free serum IgE by forming biologically inactive immune complexes with free IgE. OBJECTIVE: We hypothesized that rhuMAb-E25 would decrease total serum IgE and reduce symptoms. METHODS: Two hundred forty subjects were enrolled into five groups to determine the safety, tolerance, and efficacy of repeated administration of rhuMAb-E25 in adults with ragweed-induced allergic rhinitis and to explore the pharmacodynamic relationship of rhuMAb-E25 and IgE. One hundred eighty-one subjects received an initial intravenous loading dose (day 0, 1 month before ragweed season), followed by administration of rhuMAb-E25 (in mg/kg body weight) of 0.15 mg/kg subcutaneously, 0.15 mg/kg intravenously, or 0.5 mg/kg intravenously on days 7, 14, 28, 42, 56, 70, and 84. A subcutaneous placebo group and an intravenous placebo group were included. The total evaluation time included the 84-day treatment period, followed by a 42-day observation period. RESULTS: Adverse events were mild, and no differences were observed in the rates between the three active and two placebo treatment groups. Ragweed-specific IgE levels correlated with symptom scores. RhuMAb-E25 decreased serum free IgE levels in a dose- and baseline IgE-dependent fashion. However, only 11 subjects had IgE levels that were suppressed to undetectable levels (< or = 24 ng/ml), a sample too small to demonstrate significant differences and clinical efficacy. Thus the case for efficacy was not proven. Nonetheless, the study confirms that it is safe to repeatedly administer rhuMAb-E25 over a period of months. CONCLUSIONS: Because rhuMAb-E25 decreased serum free IgE in a dose-dependent fashion and because symptom scores correlated with antigen-specific IgE levels, the results suggest that if given in adequate doses, rhuMAb-E25 should be an effective therapy for allergic diseases.

Adolescent↗
PubMed1995

Immunotherapy: a one-year prospective study to evaluate risk factors of systemic reactions.

BACKGROUND: We did a prospective study in Atlanta, Georgia, during 1991 on the rate of systemic reactions caused by immunotherapy in a clinic that uses aqueous allergen extracts. METHODS: Immunotherapy reactions were monitored. Symptoms were recorded with respect to time of onset, involvement of respiratory tract or skin, and presence of hypotension. RESULTS: There were 98 systemic reactions in 96 patients (1 per 1600 visits or 1 per 47 patients). There was no direct relationship to seasonal pollen counts. There was, however, a correlation with the August to October increase in mold counts. There was no correlation between reactions and the age of the patient or the age of the extract. Patients were more likely to experience a reaction during the buildup phase than during maintenance therapy. The time of onset and the severity of the reaction were in agreement with previous reports. Severe reactions that included hypotension all occurred less than 30 minutes after the injection. In contrast to previous reports, patients with asthma were not at higher risk for a systemic reaction. CONCLUSION: Immunotherapy has a significant but low rate of systemic reaction. Potentially serious reactions may be mitigated by taking extra precautions during the earlier phases of an immunotherapy program and during seasons when mold counts are high.

Adolescent↗
PubMed1995

Long-term treatment of perennial allergic rhinitis with ipratropium bromide nasal spray 0.06%.

The purpose of this study was to assess the safety and efficacy of ipratropium bromide nasal spray 0.06% (aqueous solution), 84 micrograms per nostril three times a day, in reducing nasal hypersecretion in the long-term treatment of patients with perennial allergic rhinitis (PAR). This was an open-label 1-year trial. In the first 6 months all patients were treated with two puffs ipratropium bromide nasal spray 0.06%, 84 micrograms per nostril three times per day, unless they were unable to tolerate the dose. In the last 6 months the dose could be reduced to the lowest amount required to control rhinorrhea. Ninety-six patients entered the trial, and 47 completed it. Sixty-three patients completed more than 6 months of treatment. Patient and physician global evaluation suggested that ipratropium bromide nasal spray 0.06% is effective in controlling rhinorrhea associated with PAR and can contribute to control of congestion, postnasal drip, and sneezing. There was also a trend toward reduction of mucosal edema and improvement in quality of life. The most common drug-related adverse events were nasal dryness, epistaxis/nose bleed, and increased rhinitis. Most adverse events were mild and resulted in drug discontinuation in less than 10% of patients. Ipratropium bromide nasal spray was well tolerated and not associated with serious drug-related adverse events or clinically significant anticholinergic side effects. Use of ipratropium bromide nasal spray alone or with other standard medications should be considered in treating patients with PAR.

Adolescent↗
PubMed1995

Conversion from twice- to once-daily extended-release theophylline treatment in patients with reversible airway obstruction.

This multicenter, randomized, investigator-blinded, parallel group study compared the effects of converting patients from a q12h extended-release theophylline preparation (Theo-Dur) to a q24h extended-release product (Uni-Dur). Patients (n = 133) first received open-label Theo-Dur treatment with dosage titrated to achieve peak serum theophylline concentrations of 10-20 micrograms/ml. Patients then were randomized to continue Theo-Dur (n = 64) or to convert to Uni-Dur (n = 60) with peak serum theophylline concentrations maintained in the desired range. Pulmonary function tests were performed during the open-label and blinded periods; patients maintained diaries and performed peak flow measurements before each dose of study treatment. Adverse events were recorded throughout the study. Respiratory status during blinded treatment was rated as the same or improved compared with open-label treatment by > 87% of evaluable patients and physicians, regardless of treatment group. There were no significant differences in mean peak serum theophylline concentrations at baseline, at the final evaluation, or at any point during the study. Few dosage adjustments were necessary (5/52, Uni-Dur; 9/57, Theo-Dur). There were no significant changes in pulmonary function test results or patient diary entries between the open-label and blinded periods. Headache and nausea were the most commonly reported adverse events. In conclusion, converting patients from twice- to once-daily theophylline treatment resulted in no significant changes in any measures of pulmonary function, and there were no significant differences between the groups during the blinded treatment period.

Adult↗
PubMed1994

A 1-week dose-ranging study of inhaled salmeterol in patients with asthma.

STUDY OBJECTIVE: A dose-ranging study was conducted to evaluate the efficacy and safety of a new long-acting, selective beta 2-adrenoceptor agonist, salmeterol. DESIGN: Adolescents and adults (N = 160) with mild-to-moderate asthma received salmeterol (10.5, 21, 42, or 84 micrograms) or placebo by metered-dose inhaler twice daily for 1 week. Twelve-hour serial spirometry measurements were performed on the first and last days of treatment, and patients recorded their peak expiratory flow (PEF) twice daily on diary cards. RESULTS: On day 1, salmeterol produced greater bronchodilation than placebo (p = 0.001), and both the 42-micrograms and 84-micrograms doses of salmeterol were significantly more effective in improving FEV1 responses than the two lower doses of salmeterol (p < 0.05). After 1 week of treatment, all but the 21-micrograms dose of salmeterol remained statistically superior to placebo (p < 0.01), but significant differences between salmeterol doses were no longer evident, despite an apparent dose-response effect. Only the 42-micrograms and 84-micrograms doses of salmeterol sustained bronchodilation for 12 h in the majority of patients at both treatment days. The degree of improvement in morning and evening PEF was also found to be dose related. There was no significant difference among treatment groups in the overall incidence of adverse events; however, pharmacologically predictable events (eg, tremor) occurred significantly more often with salmeterol, 84 micrograms. CONCLUSIONS: Salmeterol, 42 micrograms, was similar in efficacy to 84 micrograms but was associated with a lower incidence of adverse events. Salmeterol, 42 micrograms twice daily, is a safe and effective dosage for patients with mild-to-moderate asthma who are persistently symptomatic and require maintenance bronchodilator therapy.

Administration, Inhalation↗
PubMed1994

Double-blind, clinical efficacy study comparing 400 micrograms of pirbuterol versus placebo delivered by a breath-actuated aerosol inhaler.

Pirbuterol is a selective beta-2 adrenergic agonist that is indicated for the treatment of bronchospasm in patients with asthma. Traditionally, the most common form of administration of the beta-2 agonist is by inhalation from a pressurized metered-dose inhaler. The purpose of this study was to compare the bronchodilator efficacy and safety of two inhalations (400 micrograms) of pirbuterol delivered by a breath-actuated aerosol (BAA) with that of two inhalations of a matching placebo. Patients were studied on each of two study days with a baseline electrocardiogram and sequential pulmonary function testing for 6 hr. Fourteen patients completed the study. The mean age was 32 years, with a range of 21-56 years. Most of these individuals had had asthma for more than 5 years. The mean percent increase in FEV1 was 41.2% for pirbuterol compared to 25.4% for placebo (p = 0.0038). The duration of improvement of > 15% over baseline was 4.5 hr for the pirbuterol group compared to 1.8 hr for the placebo group (p = 0.0022). There was no difference between the groups with respect to onset of action or time to reach peak effect. There was no significant difference between treatments with respect to any cardiovascular parameter. We conclude that pirbuterol in the BAA device produced significantly more bronchodilatation than did placebo with respect to its peak effect, duration of effect, and percentage change from baseline. Therefore, we feel that pirbuterol administered through the BAA device is a safe, effective means of treating both acute and chronic asthma.

Administration, Inhalation↗
PubMed1993

Evaluation of postimmunization pneumococcal titers in children with recurrent infections and normal levels of immunoglobulin.

Seven children were evaluated who had recurrent sinusitis, acute otitis media, pneumonia, and mastoiditis. All children had normal or near normal levels of IgG, IgA, and IgM. One child displayed a poor antibody response following tetanus and diphtheria immunization. Another child was noted to be atopic as determined by allergy skin tests. A polyvalent pneumococcal vaccine was administered to all children after 24 months of age, with the average age of administration being 33 months. Titers were obtained 3 to 6 weeks following immunization and were evaluated to 12 serotypes using radioimmunoassay. All seven patients failed to mount an adequate response to immunization and were treated with a course of intravenous gammaglobulin. Five of seven children showed a distinct improvement in clinical course. Children with recurrent infections and normal levels of IgG may have a depressed ability to respond to pneumococcal antigen. Evaluation of their response to pneumococcal vaccine can be used as a marker to determine their ability to make antibody specific responses to multiple infectious agents. The failure to make a specific antibody response may be one factor in the susceptibility of these patients to recurrent infections.

Antibodies, Bacterial↗
PubMed1993

Aerosol beclomethasone dipropionate compared with theophylline as primary treatment of chronic, mild to moderately severe asthma in children.

OBJECTIVE: To compare the benefits and adverse reactions of theophylline and beclomethasone (BDP) in the long-term control of mild to moderate chronic asthma in children. DESIGN: Multicentered, double-blind, double-placebo, randomized, controlled trial. PATIENTS: One hundred ninety-five children between the ages of 6 and 16 years with mild to moderate asthma. INTERVENTION: Treatment with either BDP, 84 micrograms four times a day, or sustained-release theophylline administered twice daily in doses adjusted for optimum control of symptoms. MAIN OUTCOME MEASURES: Daily diary record of symptoms, peak flow rates, supplemental bronchodilator and glucocorticoid treatment, doctor and hospital visits, absence from work and school, and side effects. RESULTS: Aerosol BDP and sustained-release theophylline were effective primary treatments for mild to moderate chronic asthma. Beclomethasone resulted in comparable symptom control with less bronchodilator use and fewer courses of systemic steroids than did theophylline. Side effects were observed significantly more frequently with theophylline than with BDP. Growth velocity suppression was noted with BDP and was more pronounced in boys. Suppression was not associated with alterations in cortisol measurements either at baseline or following stimulation. CONCLUSION: Both theophylline and BDP are effective therapy for mild to moderate asthma. Caution must be used with the administration of BDP in children because of possible growth velocity suppression.

Adolescent↗
PubMed1992

Evaluation of the Multi-Test device for immediate hypersensitivity skin testing.

Test-to-test reproducibility, user variability, and the effect of positive reactions on adjacent negative sites were evaluated for the Multi-Test skin testing device. Twenty-five subjects had skin tests with 24 histamine (1 mg/ml), four glycerosaline controls, and four "dry" controls on two testings 7 days apart. To assess reproducibility from large and smaller histamine reactions and/or their effect on adjacent negative controls, 10 of the 25 subjects were retested once with the same testing format, but histamine at 10 mg/ml was substituted. To determine whether large allergen reactions affect adjacent negative controls differently than histamine reactions, 24 additional patients were retested on arms and back with negative controls adjacent to allergens to which they had prior 3+ to 4+ skin test reactions. Conclusions from 2688 skin tests on 49 patients are as follows: large (mean > 10 mm) histamine reactions reproduced better than smaller (mean < 7 mm) responses--coefficients of variation were 12.3 and 21.4 respectively. A 14% user variability occurred when comparing mean wheal sizes from histamine produced by each nurse and 1.2% when comparing their coefficients of variation. Neither small histamine reactions nor large reactions from histamine and allergens affected adjacent negative controls. We conclude that Multi-Test is a highly reliable skin testing technique that provides good reproducibility of results and low user variability.

Adolescent↗
PubMed1992

Effect of increasing dosage of an inhaled beta-2 specific agonist on pulmonary function, tremor, and cardiovascular indices.

In this investigation we evaluated the effect of increasing dosage, using an inhaled beta-2 specific agonist, pirbuterol, administered by a metered dose inhaler on pulmonary function, tremor, and cardiovascular parameters in nonacute adult asthmatic patients. This study was conducted with a randomized crossover study design in which each individual was administered a single dose of pirbuterol (0.4, 0.8 and 1.2 mg) [corrected] on separate days. Measurements of pulmonary function, tremor (by accelerometer readings), electrocardiogram, blood pressure and pulse were obtained at 0, 15, 30, 60, 90, 120, and 180 minutes following test drug administration where appropriate. These measurements were performed until there had been no change from baseline in tremor by 60 minutes or return of tremor measurements to within 15% of baseline for up to six hours. The data demonstrated that the onset of bronchodilator effectiveness had occurred by 15 minutes after test drug administration (the first testing time). The peak percent change from baseline for the FEV1 occurred at 60 minutes after administration for all three test doses. The duration of activity was never truly established as there was no significant difference between any of the potential side effects for any of the three test drugs at any testing time period. This study demonstrated that with the beta-2 specific agent pirbuterol, administered as a metered dose inhaler, there is little risk of development of skeletal muscle or cardiovascular toxicity when as much as three times the recommended dose is used in a single usage, and that there is no direct correlation between the onset, peak, and/or duration of tremor with the onset and peak of bronchodilator efficacy with this agent.

Adolescent↗