Efficacy of Triprolidine in the Treatment of Temporary Sleep Disturbance.

Triprolidine, a first-generation antihistamine for allergic rhinitis, has a shorter half-life and fewer persistent effects relative to other antihistamines and may be useful in the treatment of temporary sleep disturbance. Patients aged ≥18 years old were randomized 1:1:1 to receive either triprolidine 2.5 mg (n = 65), triprolidine 5 mg (n = 66), or placebo (n = 67) on 3 consecutive nights. Sleep disturbance index was monitored via wrist actimeter. Subjective measures were assessed via diary card. Triprolidine 2.5 mg had a significantly lower sleep disturbance index versus placebo on night 1 (P = .02); however, when adjusted for outliers, sleep disturbance index did not significantly differ between either dose of triprolidine versus placebo on night 1. Adjusted sleep disturbance index was significantly lower with triprolidine 2.5 and 5 mg versus placebo on night 3 (P = .0017 and P = .011, respectively) and for the mean of all 3 nights (P = .01 and P = .015, respectively). Sleep latency was significantly improved for triprolidine 2.5 mg versus placebo on nights 2 and 3 and for the mean of all 3 nights and for triprolidine 5 mg versus placebo for the mean of all 3 nights. Subjective measures showed those on both doses of triprolidine felt more refreshed on awakening versus placebo for the mean of all 3 nights, with no increase in daytime sleepiness. The frequency of adverse events was similar across groups. The optimum dose of triprolidine for treatment of temporary sleep disturbance was 2.5 mg. There were improvements in both objective and subjective measures of sleep quality versus placebo, with no safety concerns raised.

Bioavailability of Triprolidine as a Single Agent or in Combination With Pseudoephedrine: A Randomized, Open-Label Crossover Study in Healthy Volunteers.

Antihistamines have been in clinical use for more than 70 years to treat allergic and nonallergic symptoms including relief from cold and flu symptoms. Despite their widespread use, pharmacokinetic (PK) data are sparse for older, first-generation antihistamines. This phase 1 single-center open-label, randomized, single-dose, 3-way crossover trial evaluated the PK profiles of 2 doses of film-coated triprolidine caplets (2.5 and 5 mg) compared with a reference combination tablet (triprolidine 2.5 mg + pseudoephedrine 60 mg) in 24 healthy adults. Blood samples were collected predose and at specified intervals across a 24-hour period after administration, and triprolidine was quantified using liquid chromatography-tandem mass spectrometry. Maximum plasma concentration of triprolidine for the 2.5 mg and dose-normalized 5 mg single-agent tablets were comparable (8.4 versus 7.1 ng/mL, respectively) and higher for the combination tablet (9.5 ng/mL). PK parameters, including time to maximum plasma concentration (∼1.5 hours) and elimination half-life (∼4 hours), were comparable between the 3 treatment arms. The safety profile of this sedating antihistamine was as expected; however, adverse effects were reported in a markedly higher proportion of women than men. There were no significant sex differences in any of the measured PK parameters.

Cocaine-like neurochemical effects of antihistaminic medications.

The pattern of activation of dopamine (DA) neurotransmission in the nucleus accumbens (NAc) of rats produced by H(1) histamine antagonists which have behavioral effects like those of psychostimulant drugs was examined. Diphenhydramine and (+)-chlorpheniramine were compared with triprolidine, a potent and selective H(1) antagonist and (-)-chlorpheniramine which is less active than its enantiomer at H(1) receptors. Affinities of the drugs to DA, serotonin, and norepinephrine transporters at H(1) receptors and potencies for DA uptake inhibition in striatal synaptosomes were determined to assess mechanisms by which the compounds increased DA levels. Intravenous diphenhydramine (1.0-3.0 mg/kg) (+)- and (-)-chlorpheniramine (1.0-5.6 mg/kg) but not triprolidine (1.0-3.0 mg/kg) elicited a cocaine-like pattern of stimulation of DA transmission with larger effects in the NAc shell than core. The absence of stereospecific effects with chlorpheniramine enantiomers along with the lack of an effect with triprolidine suggest that the effects on DA transmission were not related to H(1) receptor antagonism. Although in vivo potencies were not directly related to DA transporter affinities, it is hypothesized that actions at that site modulated by other actions, possibly those at the serotonin transporter, are primarily responsible for the neurochemical actions of the drugs on DA neurotransmission and might underlie the occasional misuse of these medications.

Treatment of the common cold.

BACKGROUND: Common colds are usually treated by the patients themselves with over-the-counter (OTC) cold medications. Many cough and cold remedies are available and sold freely without prescription. The authors conducted a study to compare the efficacy, adverse effects, the quality of life (QOL) and the patient's opinion and appreciation on the drugs (POD) between Dayquil/Nyquil and Actifed DM plus paracetamol syrup. METHOD: In this prospective, investigator-blinded clinical trial, 120 patients, aged between 15 and 60 years old, with common colds within 72 hours, who accepted the trial and gave informed written consent, were randomized into two treatment groups. One patient was excluded due to evidence of bacterial infection. Fifty-nine patients were treated with Dayquil/Nyquil (D/N group), while the other 60 patients had Actifed DM plus paracetamol (ADM/P group) for three days. On day 1 the patient's demographic data (sex, age, body weight, blood pressure, co-existing diseases/conditions, drug use, and allergy to any drugs), the most prominent symptoms and its duration were recorded. All patients were screened for bacterial infection by physical examination, complete blood count and sinus radiographs. The symptoms (nasal obstruction, rhinorrhea, sneezing, cough, sore throat, fever and headache) and signs (injected nasal mucosa, nasal discharge and pharyngeal discharge) were scored, based on 4-point scale (0 to 3), on days 1 and 4. Changing of the symptoms and QOL were recorded on the diary card. The patient's opinion and appreciation on the drugs (POD) was assessed on day 4. The effectiveness (the ability to lessen the symptoms and signs), QOL and POD between two treatments were compared. RESULTS: The demographic data between the two groups were similar. The four most common prominent symptoms of common colds in our series were cough (47.9%), sore throat (26.17%), rhinorrhea (8.4%) and headache (8.4%). However, both treatments were equally effective in lessening the symptoms (P = 0.426) and signs (P = 0.716) of common cold from days 1 to 4. The adverse effects were significantly higher in ADM/P group than in D/N group (p = 0.006). In contrast, QOL in terms of alertness, freshness and sound sleep improved from day 1 to day 3 in both treatments, but the overall day-3 score was significantly higher in the D/N group than the ADM/P group (1.85 +/- 1.83; 1.25 +/- 1.94: p = 0.024). POD in terms of convenience, flavour of drug, effectiveness of the drug and a need to repeat the drug assessed on day 4, was also significantly higher in the D/N group than the ADM/P group (10.68 +/- 2.56; 8.92 +/- 2.27: p < 0.001). CONCLUSION: Dayquil/Nyquil are as effective as Actifed DM plus paracetamol in controlling the symptoms and signs of the common cold, but have fewer adverse effects. The quality of life assessed during the use of the drugs was significantly higher in the Dayquil/Nyquil group, and according to the patients, they prefered Dayquil/Nyquil more than Actifed DM plus paracetamol.

Cardiotoxicity of new antihistamines and cisapride.

Although the new second-generation nonsedative antihistamines terfenadine and astemizole were launched as highly selective and specific H(1)-receptor antagonists, they were later found to cause prolongation of the QT-interval and severe cardiac arrhythmias. The prolongation of the QT-interval is caused by the blockade of one or more of the cardiac potassium channels, among which the delayed rectifier I(Kr), encoded by the HERG-gene, appears to be the most significant. The potency of the prokinetic drug cisapride to block I(Kr) appears to be similar to that of terfenadine (IC(50) about 50 nmol/l). These drugs cause problems when overdosed, used in combination with inhibitors of their CYP3A4-mediated metabolism, or when given to individuals with altered drug kinetics (the aged) or patients with existing cardiac disease (congenitally long QT). Moreover, interactions with other QT-interval prolonging drugs require special attention. Active hydrophilic metabolites of the second-generation antihistaminic compounds (ebastine-carebastine, loratadine-desloratadine, terfenadine-fexofenadine, astemizole-norastemizole) are new compounds with probably reduced risk for drug interactions and cardiac toxicity.

Sedation with "non-sedating" antihistamines: four prescription-event monitoring studies in general practice.

OBJECTIVES: To investigate the frequency with which sedation was reported in post-marketing surveillance studies of four second generation antihistamines: loratadine, cetirizine, fexofenadine, and acrivastine. DESIGN: Prescription-event monitoring studies. SETTING: Prescriptions were obtained for each cohort in the immediate post-marketing period. SUBJECTS: Event data were obtained for a total of 43 363 patients. MAIN OUTCOME MEASURES: Reporting of sedation or drowsiness. RESULTS: The odds ratios (adjusted for age and sex) for the incidence of sedation were 0.63 (95% confidence interval 0.36 to 1.11; P=0.1) for fexofenadine; 2.79 (1.69 to 4.58; P<0.0001) for acrivastine, and 3.53 (2.07 to 5.42; P<0.0001) for cetirizine compared with loratadine. No increased risk of accident or injury was evident with any of the four drugs. CONCLUSIONS: Although the risk of sedation was low with all four drugs, fexofenadine and loratadine may be more appropriate for people working in safety critical jobs.

Risk of ventricular arrhythmias associated with nonsedating antihistamine drugs.

AIMS: To quantify and compare the incidence of ventricular arrhythniias associated with the use of five nonsedating antihistamines: acrivastine, astemizole, cetirizine, loratadine and terfenadine. The effects of age, sex, dose, duration of treatment, and the interaction with P450 inhibitor drugs were also examined. METHODS: We carried out a cohort study with a nested case-control analysis using the UK-based General Practice Research database (GPRD). The study cohort included persons aged less than 80 years old who received their first prescription for any of the five study drugs between January 1, 1992 and September 30, 1996. We estimated relative risks and 95% confidence intervals of idiopathic ventricular arrhythmias with current use of antihistamines as compared with non use. RESULTS: The study cohort included 197425 persons who received 513012 prescriptions. Over the study period 18 valid cases of idiopathic ventricular arrhythmias were detected. Nine occurred during the current use of any antihistamine, resulting in a crude incidence of 1.9 per 10000 person-years (95%CI: 1.0-3.6) and a relative risk of 4.2 (95%CI: 1.5-11.8) as compared with non use. Astemizole presented the highest relative risk (RR= 19.0; 95%CI: 4.8-76.0) of all study drugs, while terfenadine (RR=2.1; 95%CI:0.5-8.5) was in the range of other nonsedating antihistamines. Older age was associated with a greater risk of ventricular arrhythmias (RR=7.4; 95%CI: 2.6-21.4) and seemed to increase the effect of antihistamines (RR=6.4; 95%CI: 1.7-24.8). The proportions of high dose terfenadine and the concomitant use with P450 inhibitors among current users of terfenadine were 2.7% and 3.4%, respectively over the study period with no single case of ventricular arrhythmias occurring in the presence of these two risk factors. CONCLUSIONS: The use of nonsedating antihistamines increases the risk of ventricular arrhythmias by a factor of four in the general population. Yet, the absolute effect is quite low requiring 57000 prescriptions, or 5300 person-years of use for one case to occur. The risk associated with terfenadine was no different from that with other nonsedating antihistamines.

Inhibition of histamine or allergen-induced wheals by a single dose of acrivastine, fexofenadine or cetirizine.

Certirizine, a potent H1-blocking agent, is often recommended as an emergency drug in anaphylactic reactions because of its well documented fast onset of action. In this randomized, cross-over study we compared the onset of action after a single dose of two recently introduced antihistamines, acrivastine and fexofenadine, with that of cetirizine. The inhibition of the wheal-and-flare reaction produced by skin prick test with histamine in 20 healthy volunteers and with a relevant pollen allergen in 20 atopic patients, respectively, were measured before and at regular intervals up to 60 min after the ingestion of acrivastine (8 mg and 16 mg), fexofenadine (120 mg) and cetirizine (10 mg and 20 mg). Wheal-and-flare reaction were significantly inhibited 20 min after the intake of 16 mg acrivastine in atopic patients and 30 min after intake of 8 mg acrivastine in healthy volunteers, whereas cetirizine produced a significant inhibition of the wheal-and-flare reaction within 40-60 min. No significant inhibition could be observed within 60 min after fexofenadine intake. Therefore, in clinical settings when a fast onset of the H1-blocking action is mandatory (e.g., after insect stings or for short-term prophylaxis) we recommend acrivastine.

Efficacy of acrivastine plus pseudoephedrine for symptomatic relief of seasonal allergic rhinitis due to mountain cedar.

BACKGROUND: Acrivastine is a second-generation H1-antagonist chemically related to triprolidine, but more polar and with less central nervous system penetration than triprolidine. OBJECTIVE: The efficacy of the antihistamine-decongestant combination product (Semprex-D capsules) containing acrivastine 8 mg plus pseudoephedrine HCl 60 mg was evaluated for the treatment of seasonal allergic rhinitis symptoms. METHODS: A total of 676 patients sensitive to mountain cedar pollen was enrolled into a 6-center, randomized, double-blind, placebo-controlled, parallel, 4-group study designed to compare acrivastine + pseudoephedrine, acrivastine, pseudoephedrine, and placebo. Patients with demonstrable diary symptom scores at baseline took study medication (4 doses/day) and recorded symptom scores twice daily for 2 weeks. The effectiveness of the acrivastine + pseudoephedrine combination was examined relative to the individual components and placebo in terms of changes in diary symptom scores. RESULTS: Over the 2-week period, the combination of acrivastine plus pseudoephedrine was significantly more effective than (1) acrivastine, pseudoephedrine, and placebo (P < .001) for relief of all symptoms; (2) pseudoephedrine (P < .001) for relieving allergy symptoms, ie, running nose, sneezing, itchy nose/throat and tearing; and (3) acrivastine (P < .001) for reducing nasal congestion. Relative to placebo, small increases in adverse experience rates were observed with acrivastine + pseudoephedrine for dry mouth, insomnia, somnolence, and headache. CONCLUSION: These findings in a large clinical trial demonstrate (1) the efficacy of acrivastine and (2) that each component of the combination of acrivastine 8 mg plus pseudoephedrine HCl 60 mg contributes to the overall efficacy, thereby supporting the conclusion that the combination is rational, safe, and effective for the treatment of allergic rhinitis.

Comparison of the effects of astemizole/pseudoephedrine and triprolidine/pseudoephedrine on CNS activity and psychomotor function.

The sedative properties of astemizole-D and triprolidine-D were compared in a double-blind, placebo-controlled, repeated-measures design study comprising three experimental treatments, each with a duration of 2 days (n = 12). Sedation was assessed by continuous electroencephalographic measurement (C-EEG), intermittent performance testing and subjective measures. C-EEG monitoring revealed that triprolidine-D produced significantly more daytime sedation and drowsiness than either astemizole-D or placebo (p < 0.05). Intermittent performance testing did not reveal consistent psychomotor deficits. There were no differences from placebo; the only significant findings showed that astemizole-D improved tracking accuracy at T + 65 h (p < 0.05) compared to baseline. Also, when scores were summed across all time points, astemizole-D improved scores significantly in contrast to triprolidine-D for the total scores (p < 0.05). It is concluded that, in contrast to triprolidine-D, astemizole-D does not produce daytime drowsiness or sedation.

Efficacy of acrivastine with pseudoephedrine in treatment of allergic rhinitis due to ragweed.

BACKGROUND: Semprex-D capsules contain acrivastine 8 mg (a second generation H1-antagonist) plus pseudoephedrine HCl 60 mg and were developed to satisfy the needs of allergy suffers who prefer combination products designed to provide broader symptom relief. Approval of combination products by the US Food and Drug Administration requires demonstration that each component contributes to the overall effectiveness. OBJECTIVE: The objective of the study was to demonstrate that both acrivastine and pseudoephedrine share in the efficacy of the combination in relieving allergy symptoms in patients sensitive to ragweed pollen. METHODS: This was a double-blind, randomized, placebo-controlled, parallel groups, balanced design, multicenter (13 sites) study. Patients 12 years of age or older with skin test reactivity to ragweed were recruited. Patients who qualified for the study were dispensed either (1) acrivastine + pseudoephedrine, (2) acrivastine, (3) pseudoephedrine, or (4) placebo with instructions to take one capsule 4 times daily and to record allergy symptom scores in a symptom diary 3 times daily for 14 days. Assessments of health, global allergy symptoms, protocol compliance, adverse events, and vital signs were also documented. RESULTS: A total of 702 patients were enrolled in this study. Over the 2-week period, the combination of acrivastine + pseudophedrine was significantly more effective than acrivastine, pseudoephedrine, and placebo for relief of all symptoms (P range .01 to .001); pseudoephedrine for treating symptoms responsive to antihistamines (P = .003); and acrivastine for treating symptoms responsive to nasal decongestants (P < .001). Relatively small increases in adverse experience rates were observed for the combination relative to the placebo. CONCLUSIONS: These findings in a large clinical trial demonstrate that each component of the combination of acrivastine 8 mg plus pseudoephedrine HCl 60 mg contributes to the overall efficacy, thereby supporting the conclusion that the combination is rational, safe, and effective for the treatment of allergic rhinitis.

Antihistamine effects on actual driving performance in a standard test: a summary of Dutch experience, 1989-94.

The review summarizes the major results of eight double-blind, placebo-controlled, volunteer studies undertaken by three independent institutions for showing the effects on actual driving performance of "sedating" and "nonsedating" antihistamines (respectively, triprolidine, diphenhydramine, clemastine and terfenadine, loratadine, cetirizine, acrivastine, mizolastine, and ebastine). A common, standardized test was used that measures driving impairment from vehicular "weaving" (i.e., standard deviation of lateral position (SDLP)). Logical relationships were found between impairment and dose, time after dosing, and repeated doses over 4-5 days. The newer drugs were generally less impairing, but differences existed among their effects, and none was unimpairing at doses 1-2x the currently recommended levels. One or possibly two of the newer drugs possessed both performance-enhancing and -impairing properties, depending on dose, suggesting two mechanisms of action.

[A double-blind, placebo-controlled study on the efficacy of Rinasek in symptomatic treatment of seasonal and non-seasonal rhinitis]. / Dvostruko slepa placebom kontrolisana studija za ocenu efikasnosti primene leka Rinasek u simptomatskom lecenju sezonskog i nesezonskog rinitisa.

In order to assess the efficacy of Rinasek in symptomatic treatment of seasonal and nonseasonal rhinitis, 40 ambulatory otorhinolaryngologic patients were multicentrically examined in a placebo controlled double-blind study. Clinical and other findings show that the drug worked excellent in 46.6%, well in 13.3%, weak in 13.3% and in 10% of patients it had no effects. Consequently, Rinasek worked positively in 73.2%, and that is the best reason to recommend its application.

Effects of acrivastine and terfenadine on skin reactivity to histamine.

The response to the histamine hydrochloride prick skin test was studied in 24 healthy volunteers who received, in random order and at least four days apart, acrivastine (8 mg), terfenadine (120 mg), and placebo. The tests were performed on either side of the back before and at the time of administration (single dose), then every 30 minutes for two hours, and every hour for the following four hours. Evaluation was based on the mean of two measurements of the surface area of the wheal-and-flare reaction accompanied by assessment of topical pruritus. The response to histamine was decreased markedly in the two active treatment groups. Although within one hour of injection, the activity of both antihistamines was consistently greater than that of placebo, the kinetics of action of the two products nevertheless differed; indeed acrivastine was active against flare and wheal earlier (within 30 minutes); terfenadine proved to be more active than acrivastine only on flare and only at the later times (four, five, and six hours). The safety study primarily demonstrated drowsiness in one-fourth of the patients receiving placebo and active treatment.

Acrivastine, terfenadine and diphenhydramine effects on driving performance as a function of dose and time after dosing.

The study was conducted according to a nine-way, observer- and subject-blind, cross-over design. Its purpose was to compare the single-dose effects of the following drugs on driving performance: acrivastine (8, 16 and 24 mg); the combination of acrivastine (8 mg) with pseudoephedrine (60 mg); terfenadine (60, 120 and 180 mg); diphenhydramine-HCl (50 mg); and placebo. The subjects were 18 healthy female volunteers. Drug effects were assessed in two repetitions of two driving tests (highway driving and car-following) after each treatment. Acrivastine's impairing effects in both driving tests were similarly dose-related. The 8-mg dose had a small, but significant, effect on highway driving in the first trial. The 16-mg and 24-mg doses significantly impaired driving in both tests during the first trial and the 24-mg dose did so again during the second trial. Neither the combination of acrivastine with pseudoephedrine nor terfenadine caused any significant impairment of performance. Diphenhydramine significantly impaired driving in both tests during every trial. In conclusion, the normal therapeutic dose of acrivastine (8 mg) had little effect on driving performance, and virtually none when that dose was given in combination with pseudoephedrine (60 mg). Higher doses of acrivastine severely impaired driving performance. Terfenadine had no significant effect on driving performance after any dose while diphenhydramine strongly impaired every important driving parameter.