The eternal triangle: benefit, risk, and cost of therapeutic agents

The cost of treating allergic rhinitis

Allergic rhinitis is a high-cost, high-prevalence disease. In the year 2000, over $6 billion was spent on prescription medications to treat this illness. Although it is not associated with severe morbidity and mortality, allergic rhinitis has a major effect on the quality of life of the more than 50 million Americans with this illness. Intranasal corticosteroids (INCS) and nonsedating antihistamines (NSAH) are the most common prescription medications for this disease. INCS are recognized as the most effective treatment regimen for chronic symptoms. NSAH are perceived as important in the treatment of patients with mild disease, or as add-on therapy to INCS. When the literature is reviewed, the INCS produce the greatest decrease in total nasal symptom scores, the largest effect size, when compared with NSAH. Both classes of medications produce similar effects on concurrent allergic conjunctivitis. Further recent studies indicate that the INCS are also superior when used on an as-needed basis, and that there is little clinical benefit from the addition of loratadine to intranasal fluticasone. INCS have lower average wholesale prices as a class than the NSAH. Since the INCS are the dominant medication in efficacy studies and cost less, cost-effectiveness studies always favor intranasal corticosteroids.

Sedation and antihistamines: a review of inter-drug differences using proportional impairment ratios

The use of antihistamines (AHs) has until recently been associated with a number of undesirable side effects, the most troublesome of which is sedation. There are two aspects to sedation. The first, an objectively determined measure based on the results of psychometric tests from controlled trials, and the second, the subject's response to the administration of a drug. Since AHs are largely used in ambulant patients, a complete evaluation of sedation should be performed through standardised objective and subjective tests, shown to be sensitive to the central effects of AHs.An extensive review of the literature identified 76 studies of H(1) receptor antagonists in healthy volunteers, in which assessment of sedation was the primary objective. Results from studies published in peer-reviewed journals which employed a placebo condition as well as a positive internal control using a crossover design were analysed to determine the extent to which a particular antihistamine produced impairments on a battery of psychometric tests. The impairment index for each antihistamine was calculated and subsequently compared with the impairment index obtained for all other AHs.The calculation of this proportional impairment ratio enabled the sedative potential of an individual antihistamine to be identified relative to all other AHs and thus allowed the ranking of AHs with respect to their ability to cause impairments of cognitive and psychomotor function.Findings from this review clearly demonstrate that there are distinct classes of AHs with respect to their ability to impair cognitive function and psychomotor performance. Copyright 2000 John Wiley & Sons, Ltd.

Pharmaceuticals--cost or investment? An employer's perspective

Employers are becoming increasingly concerned about rising pharmaceutical costs. Are improved health and cost outcomes achieved as a result of increasing pharmaceutical costs? One should approach this issue with a holistic view that considers the overall impact that disease conditions have on health and productivity. To illustrate, we first identified the "top ten" most expensive physical and mental health concerns facing American businesses, using data from over 60 firms from the 1996 MarketScan Private Pay Fee-For-Service Research Database. For some of these top ten conditions, the literature already addresses the drug cost versus investment issue, with mixed results. For conditions in which uncertainty prevails and for other high-cost conditions, empirical analyses should address the drug cost versus investment issue to minimize the risk of a penny-wise and pound-foolish payment/coverage policy. A similar strategy should be applied to individual corporate diagnostic assessments.

Toxicity of drugs used for treatment of rhinitis: a reminder to the otorhinolaryngologist

We retrospectively studied files on toxicity of drugs used for treatment of rhinitis (nasal antihistamines, oral antihistamines, nasal vasoconstrictors, oral decongestants, nasal corticosteroids, nasal anticholinergic agent, nasal mast cell stabilizer, and respiratory antigen preparations for oral use) that occurred in São Paulo, Brazil, from 1 July 1996 to 30 June 1998. There were 823 cases of toxicity by these agents, with a predominance of oral decongestants (in combination with antihistamines) (53.4%). There was a significant incidence of toxicity within children aged 1 to 4 years (P < 0.05) and a preponderance among males aged 5-9 years and females aged 10-39 years. Accidental intake of medicines accounted for the majority of toxicity cases (57.2%).

H1-receptor antagonists: safety issues

Histamine is an important neurotransmitter. Old (first-generation) H1-receptor antagonists such as chlorpheniramine, diphenhydramine, or triprolidine produce histamine blockade at H1-receptors in the central nervous system (CNS) and frequently cause somnolence or other CNS adverse effects. New (second generation) H1-antagonists such as cetirizine, fexofenadine, and loratadine represent an advance in therapeutics; in manufacturers' recommended doses, they enter the CNS in smaller amounts, produce relatively little somnolence or other CNS adverse effects, and do not exacerbate the adverse CNS effects of alcohol or other CNS-active chemicals. Two H1-antagonists, astemizole and terfenadine, have been found to prolong the QTc interval and, rarely, to cause cardiac dysrhythmias after overdose or under other specific conditions. This has led to withdrawal of regulatory approval for them. An H1-antagonist absolutely free from adverse effects under all circumstances is not yet available for use.

Non-cardiac adverse effects of antihistamines (H1-receptor antagonists)

Antihistamines, available without prescription in many countries, are generally considered to be safe medications; however, the old first-generation H1 antagonists commonly cause adverse central nervous system (CNS) effects, even when administered in usual doses. Patients may not be aware of these effects and do not necessarily develop tolerance to them. In contrast, the new, second-generation H1 antagonists are relatively free from adverse effects in the CNS, primarily because they do not cross the blood-brain barrier and block the important neurotransmitter function of histamine. Most of the H1 antagonists in current use are unlikely to cause cardiac toxicity. There is no evidence that H1 antagonists, which have been approved by regulatory agencies, have carcinogenic, tumour-promoting, or teratogenic effects in humans.

Brompheniramine maleate: a double-blind, placebo-controlled comparison with terfenadine for symptoms of allergic rhinitis

This was a double-blind, randomized, placebo-controlled, multicenter, parallel study comparing the effectiveness, at recommended doses, of an extended-release formulation of brompheniramine maleate and terfenadine in the treatment of allergic rhinitis. Subjects with symptoms of seasonal and/or perennial allergic rhinitis received brompheniramine 12 mg (n = 106), 8 mg (n = 105), terfenadine 60 mg (n = 106), or placebo (n = 53) twice daily for 14 days. On treatment days 3, 7, and 14, symptom severity ratings (i.e., rhinorrhea, sneezing, nasal congestion, itchy nose, eyes or throat, excessive tearing, postnasal drip) were completed by the physician; subjects and physicians each completed a global efficacy evaluation. Brompheniramine 12 mg and 8 mg and terfenadine were more effective than placebo (p < or = 0.05) on the physicians' global: brompheniramine 12 mg was more effective than terfenadine (p < or = 0.05) on days 7 and 14 and brompheniramine 8 mg on day 3. On the subjects' global evaluation, brompheniramine 12 mg and 8 mg and terfenadine were more effective than placebo (p < or = 0.05); brompheniramine 12 mg was more effective than terfenadine (p < or = 0.05) on days 7 and 14 and brompheniramine 8 mg on day 3. In general, brompheniramine 8 mg was comparable to terfenadine. On days 3 and 7, the total symptom and total nasal symptom severity scores for subjects receiving brompheniramine 12 mg were significantly more improved than for placebo (p < 0.05); terfenadine was not different from placebo; brompheniramine 12 mg was significantly better than terfenadine on day 7 (p < 0.05) for reducing total symptom severity and on days 3, 7, and 14 for reducing total nasal symptom severity. Adverse experiences were reported by 155 (41.9%) of the 370 subjects enrolled in the study. The overall rate of adverse experiences in the brompheniramine 12 mg treatment group (57.5%) was significantly greater (p < 0.05) than for brompheniramine 8 mg (38.1%), terfenadine (31.1%), and placebo (39.6%). In conclusion, an extended-release formulation of brompheniramine 12 mg or 8 mg bid alleviates allergic rhinitis symptoms and brompheniramine 12 mg provides significantly better relief of these symptoms than terfenadine 60 mg bid.

Brompheniramine, loratadine, and placebo in allergic rhinitis: a placebo-controlled comparative clinical trial

A double-blind, randomized, placebo-controlled, parallel-group, multicenter study was conducted to compare the effectiveness of an extended-release formulation of a classical antihistamine, brompheniramine, and a second-generation compound, loratadine, in the treatment of allergic rhinitis. Subjects with symptoms of allergic rhinitis received brompheniramine 12 mg twice daily (n = 112), loratadine 10 mg once daily (n = 112), or placebo twice daily (n = 114) for 7 days. Study medications were blinded using a double-dummy technique. Subjects completed an overall evaluation of symptom relief on a daily basis and returned on treatment days 3 and 7, at which times the investigator assessed symptom severity. The investigator and subject each completed a global efficacy evaluation, and subjects were interviewed regarding adverse experiences. The primary efficacy variable was the physicians' global efficacy evaluation on day 3. Symptoms also were analyzed as summed severity scores for all symptoms and for the nasal symptom cluster of rhinorrhea, sneezing, and nasal blockage. At all post-baseline evaluations (days 3, 7, and averaged over the two days), brompheniramine was significantly better than loratadine and placebo for both sets of summed symptom scores and all three global assessments. Loratadine was significantly better than placebo for physician ratings of total symptom severity averaged over the two days and for the physician and subject ratings of the nasal cluster on day 3. Central nervous system-related symptoms were the most frequently reported adverse experiences; somnolence was reported most frequently by patients taking brompheniramine, and its occurrence was less frequent as treatment continued. A nonprescription, extended-release formulation of brompheniramine 12 mg twice daily provided significantly better relief of symptomatic allergic rhinitis than loratadine 10 mg once daily.