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PubMed1990

Interactive effect of ethanol administration on blood hydroxyzine levels in rabbits.

Mechanism of a rise of blood hydroxyzine concentrations (BHC) due to ethanol administration was investigated used rabbits. When 10 mg/kg hydroxyzine dihydrochloride were orally administered together with 10 ml/kg of 1 to 15% ethanol solution, BHC raised in all rabbits given ethanol solution more than 10%. When 10 ml/kg of 15% ethanol solution were orally administered at 1, 2 or 3 hours before oral administration of hydroxyzine, BHC raised markedly in all cases. BHC raised little or a little when hydroxyzine were orally administered immediately after intravenous administration of 5 ml/kg of 20% ethanol solution. It was considered that the main mechanism of a rise of BHC was not metabolic interaction between hydroxyzine and ethanol, but an enhancement of intestinal absorption of hydroxyzine due to ethanol. It was also found that hydroxyzine in blood distributed rapidly into bodily tissues.

Animals↗
PubMed1986

Cimetidine increases the plasma concentration of hydroxyzine.

The combination of hydroxyzine and cimetidine is reported to be more effective than hydroxyzine alone in chronic urticaria. The plasma concentration of hydroxyzine was studied in seven patients treated both with the hydroxyzine 25 mg t.i.d. and the combinations of hydroxyzine 25 mg and cimetidine 200 mg t.i.d. Hydroxyzine plasma concentrations were definitely higher during the combination treatment than during hydroxyzine alone. This may explain the effectiveness of the combination treatment.

Chronic Disease↗
PubMed1984

A controlled double-blind comparison of intramuscular lorazepam and hydroxyzine as surgical premedicants.

The safety and efficacy of lorazepam and hydroxyzine, administered intramuscularly for surgical premedication, were compared in a double-blind placebo-controlled study. Ninety patients were given either 0.05 mg/kg of lorazepam (maximum 4 mg), 1.5 mg/kg of hydroxyzine (maximum, 100 mg), or 1 ml of normal saline before surgery. By 60 min after injection, patients given lorazepam or hydroxyzine were significantly (P less than 0.05) more sedated than the placebo-treated patients. The sedative effect of lorazepam lasted longer than that of hydroxyzine. Baseline anxiety scores were low; thus differences in the anxiolytic effect of the test drugs were not detected. Lorazepam-treated patients were consistently less able to recall postinjection events than patients treated with hydroxyzine or placebo. The frequency of injection-site reactions was similar in the three treatment groups. Premedication with lorazepam was considered satisfactory by a higher percentage of patients (77%) than was that with hydroxyzine (62%) or placebo (34%); only lorazepam was considered significantly (P less than 0.005) superior to placebo. The advantages of a longer duration of sedative effect, a greater effect on recall, and higher patient acceptance favor the use of lorazepam over hydroxyzine for surgical premedication.

Adolescent↗
PubMed1993

Effect of hydroxyzine and meperidine on arterial blood gases in patients with chronic obstructive pulmonary disease.

Hydroxyzine is frequently used to tranquilize chronic obstructive pulmonary disease patients, who may be concomitantly receiving narcotic analgesics. Therefore, its effect alone and in combination with meperidine on arterial blood gases and ventilation at rest were evaluated in 44 patient volunteers, who gave informed consent. Hydroxyzine, 1.5 mg/kg i.v. caused no significant decrease in PaO2 and pH, no increase in PaCO2 at 5, 10, 20, 30 and 60 min post-infusion (n = 13, mean age = 63.4 years). Meperidine, 1.5 mg/kg i.v. caused a significant (p < 0.001) reduction in PaO2 for 20 min with concomitant increase in PaCO2 (n = 14; mean age = 49.4 years). The combination of the same doses of hydroxyzine with meperidine i.v. caused no greater decrease in PaO2 or in pH or increase in PaCO2 than did meperidine alone (n = 17; mean age = 52.6 years), indicating no greater ventilatory depression with the combination than with meperidine alone. The lack of significant pH decreases at 30 and 60 min further corroborates no potentiation of meperidine by hydroxyzine. In conclusion, hydroxyzine, even when given through the i.v. route in excess of the maximum i.m. therapeutic dose, caused no changes in PaO2, PaCO2 or pH in chronic obstructive pulmonary disease patients. Therefore, its i.m. administration resulting in lower blood levels than i.v., is not likely to cause ventilatory depression. Furthermore, hydroxyzine caused no potentiation of the ventilatory depression induced by meperidine, hence hydroxyzine may be safely employed in combination with meperidine.

Aged↗
PubMed1991

Peripheral antihistamine and central sedative effects of single and continuous oral doses of cetirizine and hydroxyzine.

The peripheral histamine-inhibiting and central sedative effects of single oral doses (SOD) and of repeated administration for one week (steady state, SS), of 20 mg hydroxyzine HCL and 10 mg cetirizine have been assessed in 12 healthy volunteers, in a double-blind placebo-controlled cross-over study. Peripheral H1-receptor antagonism was estimated as the reduction in the area of the flare and the duration of the itch after intradermal injection of histamine 0.1 and 1.0 micrograms. CNS effects were assessed by a battery of computerized neuropsychological tests and seven visual analogue scales. Drug compliance was ascertained by plasma level determinations. Cetirizine 10 mg (SOD) produced a more pronounced peripheral effect than 20 mg hydroxyzine, whereas hydroxyzine but not cetirizine, showed a significant sedative action in the relevant rating scales. These effects vanished during steady state, suggesting adaptation to the initial sedative effect of hydroxyzine in most of the subjects. No sedative effect of cetirizine was demonstrated. There was no impairment at group level in the neuropsychological tests after the SOD or SS treatment. However, six subjects who showed sedation in the analogue ratings after hydroxyzine, displayed significantly impaired performance after hydroxyzine SOD. The findings are discussed in relation to the individual characteristics of the study groups.

Administration, Oral↗
PubMed1979

Suppression of seasonal allergic rhinitis symptoms with daily hydroxyzine.

The effectiveness of hydroxyzine in the suppression of allergic rhinitis symptoms was evaluated using a double-blind, parallel study design during the 1977 ragweed season. Forty-three subjects with positive ragweed skin tests and a history of an exacerbation of symptoms during August and September of the previous two years were randomly assigned to receive either hydroxyzine or placebo. Subjects scored the severity and duration of symptoms in a daily diary and adverse effects were evaluated from a structured interview at two-week intervals. Although drowsiness and dry mouth were frequent initially among the hydroxyzine-treated patients, these minor side effects rapidly disappeared as the dose was slowly increased, and all but one subject tolerated 150 mg/day. Subsequently, during the period of the highest ragweek pollen counts, the hydroxyzine-treated group spent significantly more days free of symptoms or with only mild sneezing, rhinorrhea, and eye symptoms than subjects who took placebo (p less than 0.05). Thus, hydroxyzine appeared to be well tolerated on a continuous daily basis and was effective in suppressing most of the symptoms of seasonal allergic rhinitis. Comparison of hydroxyzine with antihistamines more traditionally used for allergic rhinitis appears warranted.

Adult↗
PubMed1984

The pharmacokinetics and antihistaminic of the H1 receptor antagonist hydroxyzine.

We studied the pharmacokinetics and the suppression of histamine-induced wheals, flares, and pruritus in the skin after administration of the histamine H1 antagonist hydroxyzine to seven healthy adults. After a single oral dose of hydroxyzine, 0.7 mg/kg (mean dose 39.0 +/- 5.4 mg), the mean maximum serum hydroxyzine concentration of 72.5 +/- 11.1 ng/ml occurred at a mean time of 2.1 +/- 0.4 hr. The mean elimination half-life calculated from the terminal linear portion of the serum hydroxyzine concentration vs. time curve was 20.0 +/- 4.1 hr. The mean clearance rate was 9.78 +/- 3.25 ml/min/kg and the mean volume of distribution was 16.0 +/- 3.0 L/kg. The single dose of hydroxyzine suppressed pruritus at the wheal and flare sites from 1 to 36 hr. Maximal suppression of the wheals was 80% and maximal suppression of the flares was 92%. Significant suppression of the wheals and flares persisted for 36 and 60 hr, respectively. Pharmacodynamic analysis of the wheal and flare suppression data and the mean serum hydroxyzine concentrations supports the prolonged terminal serum half-life value for the drug.

Adult↗
PubMed1989

Prolongation of simple and choice reaction times in a double-blind comparison of twice-daily hydroxyzine versus terfenadine.

Newer, nonsedating antihistamines provide a therapeutic alternative for the patient with allergy whose work is impaired by the side effects of traditional H1 antihistamines. To assess the differential effect of these antihistamines on reaction times and subjective symptoms, we compared terfenadine, 60 mg twice daily, to hydroxyzine, 25 mg twice daily, in a double-blind, placebo-controlled, crossover study of 16 healthy, asymptomatic adults. Simple reaction time and choice reaction time were measured with a computer-based, eye-hand, reaction-time testing apparatus. Reaction times and symptom scores were assessed 90 minutes after the fourth and tenth doses of each drug. Hydroxyzine, but not terfenadine, significantly prolonged both simple and choice reaction time (p less than or equal to 0.0001). However, decision time, the time to process one bit of spatial information, was not prolonged by either antihistamine. Therefore, hydroxyzine prolonged the interpretation and response to stimuli of the central nervous system without increasing single-bit processing time. Although terfenadine was not different from placebo for any symptom assessed, hydroxyzine produced significant drowsiness (p = 0.001), dry mouth (p = 0.022), and irritability (p = 0.021). During the 5 days of hydroxyzine administration, neither objective nor subjective symptoms demonstrated the development of tolerance. No correlation was found between subjective symptoms and prolongation of reaction times by hydroxyzine, suggesting that side effect symptoms of traditional antihistamines are unreliable predictors of objective performance. Terfenadine provides a promising therapeutic alternative to traditional antihistamines for individuals performing critical tasks.

Adult↗
PubMed2006

Sulpiride plus hydroxyzine decrease tinnitus perception.

OBJECTIVES: The aim of the study is to confirm the effectiveness of sulpiride and hydroxyzine in tinnitus patients. The administration of sulpiride, a D2 antagonist of dopamine receptors, together with hydroxyzine, a subcortical sedative, covers the areas of tinnitus perception. METHODS: A prospective, randomized, single blinded, placebo-control study was done in general otorhinolaryngology consultations for 2002-2004 in Seville and Zaragoza (Spain). One hundred and fifty patients consulted for subjective tinnitus. They were included randomly in three groups of 50. A group took sulpiride (50 mg/8 h) alone, other the same dose of sulpiride plus hydroxyzine (25 mg/12 h), and the third placebo (lactose), for 1 month. One hundred and twenty-two patients completed the study. Clinical history, tonal audiometry, tympanometry, and tinnitometry were done in the beginning and end of the study. Subjective Grading of Tinnitus Perception and visual analogical scale (0-10) were done for result evaluation. RESULTS: Based on the Subjective Grading of Tinnitus Perception, tinnitus perception diminished by 56% in patients treated with sulpiride and by 81% in patients treated with sulpiride plus hydroxyzine. Based on the visual analogical scale, tinnitus perception diminished from 7.8 to 6.3 in the patients treated with sulpiride, and from 7.8 to 5.1 in those treated with sulpiride plus hydroxyzine. CONCLUSIONS: Sulpiride plus hydroxyzine decreases tinnitus perception. Tinnitus auditolimbic dopaminergic pathway opens wide therapeutical implications.

Adult↗
PubMed2005

Transport of hydroxyzine and triprolidine across bovine olfactory mucosa: role of passive diffusion in the direct nose-to-brain uptake of small molecules.

Hydroxyzine and triprolidine have both been reported to reach the CNS following nasal administration. The objective of this study was to investigate their in vitro permeation across bovine olfactory mucosa in order to further characterize the biological and physicochemical parameters that influence direct nose-to-brain transport. In vitro experiments were conducted using Sweetana-Grass (Navicyte) vertical diffusion cells to evaluate the effect of directionality, donor concentration and pH on the permeation of hydroxyzine and triprolidine across excised bovine olfactory mucosa. These studies demonstrated that the Jm-s (mucosal-submucosal flux) and Js-m (submucosal-mucosal flux) of hydroxyzine and triprolidine across the olfactory mucosa were linearly dependent upon the donor concentration without any evidence of saturable transport. Hydroxyzine inhibited the efflux of P-gp substrates like etoposide and chlorpheniramine across the olfactory mucosa. Both hydroxyzine and triprolidine reduced the net flux (Js-m-Jm-s) of etoposide with IC50 values of 39.2 and 130.6 microM, respectively. The lipophilicty of these compounds, coupled with their ability to inhibit P-gp, enable them to freely permeate across the olfactory mucosa. Despite the presence of a number of protective barriers such as efflux transporters and metabolizing enzymes in the olfactory system, lipophilic compounds such as hydroxyzine and triprolidine can access the CNS primarily by passive diffusion when administered via the nasal cavity.

Animals↗
PubMed1998

Hydroxyzine inhibits neurogenic bladder mast cell activation.

OBJECTIVES: Increased numbers of activated mast cells have been documented close to substance P (SP) containing nerve endings in the bladders of patients with interstitial cystitis (IC), a painful, sterile bladder disorder occurring primarily in females. Many of these patients also suffer from allergies, but common antihistamines do not help. In line with the fact that IC symptoms worsen under stress, we recently showed that bladder mast cells could be activated by the stable acetylcholine (Ach) analogue carbachol and by immobilization stress. Preliminary data from open label studies indicated that the heterocyclic histamine-1 receptor antagonist (H-1r alpha) hydroxyzine reduces IC symptoms. We, therefore, investigated whether hydroxyzine could inhibit carbachol-induced bladder mast cell activation. METHODS: Bladder pieces from male Sprague-Dawley rats were perfused with 10(-5) M carbachol, 10(-5) M SP, or 100 microg/ml compound 48/80 (C48/80), with or without preincubation with the designated concentrations of the H-1r alpha. Mast cell activation was assessed by release of exogenous 3H-serotonin and morphological evidence of secretion by light microscopy. RESULTS: Carbachol at 10(-5) M triggered rat bladder mast cell serotonin release which represented a 65% increase over control. Equimolar concentrations of SP caused a 32% increase, while C48/80 had no effect. The heterocyclic piperazine H-1r alpha hydroxyzine reduced carbachol-induced serotonin release by 25% at 10(-6) M and 34% at 10(-5) M, both of which were statistically significant (P < 0.05). On the contrary, the well known H-1r alpha diphenhydramine had no inhibitory effect, while the mixed H-1r alpha and 5-hydroxytryptamine-receptor antagonist (5-HTr alpha) azatadine actually caused an 11% increase. CONCLUSION: Hydroxyzine reduced carbachol-induced serotonin release from rat bladder in vitro through a mechanism which was unrelated to its H-1 receptor antagonistic properties. The ability of hydroxyzine to inhibit bladder mast cell activation by neurogenic stimuli along with its anticholinergic, anxiolytic and analgesic properties, may explain the clinical efficacy of this drug in reducing IC symptoms. Other, nonsedating, hydroxyzine analogues able to inhibit bladder mast cell activation may provide potentially new therapeutic approaches for IC.

Animals↗
PubMed2005

Hydroxyzine- and cetirizine-loaded liposomes: effect of duration of thin film hydration, freeze-thawing, and changing buffer pH on encapsulation and stability.

PURPOSE: To assess the effect of the duration of film hydration, freeze-thawing, and changing buffer pH on the extent of entrapment of hydroxyzine and cetirizine, H1-antihistamines with different polarity, into liposomes, and the stability of these liposomes. METHODS: Multilamellar vesicles (MLV) were prepared by thin-lipid film hydration using L-alpha-phosphatidylcholine (PC) and buffer containing 80 mg hydroxyzine at pH 7. For MLV containing hydroxyzine, the liposomes were subjected to 1) hydration for 1 h, 24 h, or 48 h for the control batch, batch B, or batch D respectively; and 2) hydration for 1 h, 24 h, or 48 h with freeze-thawing for 5-cycles for batch A, batch C, or batch E, respectively. These formulations were stored at 10 +/- 2 degrees C and 37 +/- 0.1 degrees C. Small unilamellar vesicles (SUV) and MLV were prepared using L-alpha-phosphatidylcholine (PC), and buffer at pH 5.0, 5.5, 6.0, 6.5, and 7.0, containing 80 mg hydroxyzine or 82 mg cetirizine by the ethanol injection and thin-lipid film hydration methods, respectively. These formulations were stored at 10 +/- 2 degrees C. Liposomes were evaluated immediately after preparation and after storage by determining percent entrapment of hydroxyzine (PETH) or of cetirizine (PEC) and by observing changes in the physical appearance (PA). Particle size (PSA) of the liposomes freshly prepared at pH=6.5 was measured from transmission electron micrographs (TEM). RESULTS: Increasing thin-film hydration time or repeated freeze-thawing did not affect the initial PETH or long-term stability of control, A, B, C, D, and E batches of MLV containing hydroxyzine stored at 10 +/- 2 degrees C. At 37 +/- 0.1 degrees C, PETH of all MLV batches decreased considerably after 1 month. This was more evident in batches B, C, and E exposed to freeze-thawing. The PETH of SUV increased markedly from 53.0% to 84.0% when the pH of the buffer was increased from 5.0 to 5.5. As pH increased from 6.0 to 7.0, PETH continued to increase from 84% to 94%. The initial PETH of MLV increased slightly from 82.0% to 94.0% as the buffer pH values increased from 5.0 to 7.0. There was no effect of pH on initial PEC, and stability of SUV or initial PEC of MLV, which ranged from 92% to 94%, as buffer pH values increased from 5.0 to 6.5. After storage at 10 +/- 2 degrees C PEC in MLV decreased from 94% to 74%. CONCLUSIONS: The freeze-thawing processes had some effect on the stability of liposomes stored at temperatures higher than ambient temperature, 37 +/- 0.1 degrees C. The effect of changing the buffer pH from 5.5 to 7.0, and from 5.0 to 6.5 on initial PETH and PEC, respectively, was minimal. After 24 months at l0 +/- 2 degrees C, pH had no effects on PETH; however, PEC of MLV decreased.

Cetirizine↗
PubMed2007

Histamine H1 blocker hydroxyzine improves sleep in patients with cirrhosis and minimal hepatic encephalopathy: a randomized controlled pilot trial.

OBJECTIVES: Sleep difficulty is common in minimal hepatic encephalopathy (HE) and the mechanisms are not fully elucidated. Dysregulated histamine neurotransmission is associated with an altered circadian rhythmicity that is partially restored following central histamine H1 receptor blockade in cirrhotic animals. We studied the effects of the histamine H1 blocker hydroxyzine in sleep alterations in patients with cirrhosis in a double-blind, randomized controlled fashion. METHODS: A total of 35 patients (age 56 yr [36-69], Pugh's score 9 [7-12], portosystemic shunt: N = 7) with minimal HE and long-standing sleep difficulties (8 months [4-48]) and free from benzodiazepines were randomized to hydroxyzine 25 mg at bedtime (N = 17) or placebo (N = 18) for a 10-day period. Measurements of sleep behavior using visual analog scale and wrist actigraphy, neuropsychological tests, and protein s100beta serum levels were performed at baseline and at day 10. RESULTS: Subjective improvement in sleep was observed in 40% of hydroxyzine-treated patients but in none receiving placebo (P < 0.04). Objectively, 65% of hydroxyzine-treated patients versus 25% of patients under placebo had a >or=30% increase in sleep efficiency as measured by wrist actigraphy (P < 0.04). Neuropsychological tests (Z scores) and protein s100beta levels remained statistically unchanged in both groups. One patient developed an acute episode of encephalopathy reversible upon cessation of hydroxyzine. CONCLUSIONS: In contrast to placebo, hydroxyzine 25 mg at bedtime improved sleep behavior (subjectively and using wrist actigraphy) in patients with cirrhosis and minimal HE. The risk of precipitating overt HE warrants some caution when prescribing this drug.

Adult↗
PubMedDate not supplied

Relative efficacy and safety of loratadine, hydroxyzine, and placebo in chronic idiopathic urticaria and atopic dermatitis.

The subjects of this double-blind study were 59 patients with chronic idiopathic urticaria or atopic dermatitis randomly assigned to receive 10 mg of loratadine once daily and placebo twice daily (n = 20), 25 mg of hydroxyzine thrice daily (n = 20), or placebo thrice daily (n = 19). The patients (15 men, 44 women) were aged 18 to 65 years. Among the 18 patients with urticaria and 41 with atopic dermatitis, daily symptom scores decreased 43% and 57% in those receiving loratadine, 47% and 38% in those receiving hydroxyzine, and 0% and 33% in the placebo patients. The difference between the treated and placebo patients was significant among the urticaria patients. According to a global evaluation of treatment effects, more treated than placebo patients reported marked or complete symptom relief; among the patients with atopic dermatitis, the difference was significant between the loratadine and placebo patients. Somnolence or sedation during treatment was reported by one of the patients receiving loratadine, by eight of the hydroxyzine patients, and by two of the placebo patients; the difference between the loratadine and hydroxyzine patients was significant. It was concluded that loratadine is as effective as hydroxyzine in the treatment of urticaria and demonstrates a significant antipruritic effect in atopic dermatitis, but does not have the central nervous system effects of hydroxyzine.

Adolescent↗
PubMed1986

Theophylline plus hydroxyzine versus theophylline monohydrate in the treatment of asthma.

The efficacy of 281.7 mg of theophylline monohydrate and a combination of theophylline (240 mg) + hydroxyzine (7.5 mg) were compared in a double-blind, crossover, placebo-controlled study in 15 patients with chronic reversible bronchial asthma. The patients took the drugs tested at 7.00 a.m., 3.00 p.m. and 10.00 p.m. During the 3-day trial period, the patients measured their peak expiratory flow (PEF) values every day at 7.00 a.m., 10.00 a.m. and 10.00 p.m., and during the last trial day, theophylline serum levels were also determined. Use of theophylline monohydrate resulted in slightly steadier serum theophylline levels than with theophylline + hydroxyzine and morning levels of theophylline were significantly higher (p less than 0.01) during the former treatment. Despite this, only the theophylline + hydroxyzine combination had a significant effect (p less than 0.05 at 7.00 a.m., p less than 0.01 at 10.00 a.m. and 10.00 p.m.) on PEF values at each time of measurement. There was a significant difference (p less than 0.05) in PEF values at 10.00 a.m. between the trial preparations in favour of the theophylline + hydroxyzine combination. Theophylline + hydroxyzine significantly decreased (p less than 0.05) nocturnal dyspnoea and most patients preferred this preparation. The differences in side effects were not statistically significant. The addition of hydroxyzine to theophylline increases the clinical efficacy of the latter.

Adult↗
PubMed1981

Respiratory depression of intravenous hydroxyzine in man: potency, duration, and lack of reversal by naloxone.

The effects of intravenous hydroxyzine and hydroxyzine with naloxone on respiration were determined in man. Drug effect was expressed as the shift in the 20-L intercept of the respiratory response curve measured by a rebreathing technique. The time-effect curve of hydroxyzine was found to be the same for hydroxyzine alone and in combination with naloxone, but significantly different from placebo or naloxone alone. The duration of respiratory depression in man resulting from hydroxyzine, 100 mg IV, is greater than 3 hours. Our data did not support the hypothesis that the respiratory depressant and recently discovered antinociceptive effects of hydroxyzine result from endorphin release or are mediated by opiate receptors.

Adult↗
PubMed1989

Effect of hydroxyzine and meperidine on arterial blood gases in healthy human volunteers.

Because hydroxyzine hydrochloride is frequently used to tranquilize patients, who are receiving narcotic analgesics for pain relief, its effect alone and in combination with meperidine on arterial blood gases and ventilation in patients at rest was evaluated in 65 healthy volunteers, who gave informed consent. Hydroxyzine hydrochloride, 1.5 mg/kg IV given over 30 seconds, caused no decrease but rather a significant (P less than .001) increase in PaO2 and no increase in PaCO2 and/or pH at 5, 10, 20, 30, and 60 minutes (N = 29; mean age = 47.0 years). Meperidine, 1.5 mg/kg IV given over 30 seconds, caused a significant (P less than .01) reduction in PaO2 at 5 minutes indicating ventilatory depression but no increase in PaCO2 and/or pH (N = 19; mean age = 32.4 years). The combination of the same doses of hydroxyzine with meperidine IV caused a significantly greater decrease in PaO2 only at 10 minutes but a greater increase in PaCO2 and pH at all times for 60 minutes than did meperidine alone (N = 17; mean age = 39.5 years), which indicates greater ventilatory depression with the combination than with hydroxyzine alone. However, PaO2, PaCO2 and pH remained within the awake normal ranges for PaO2, PaCO2, and pH for the age group of volunteers even at 10 minutes after IV injection of the drug combination when most of the volunteers were asleep. In conclusion, hydroxyzine even when given IV in excess of the maximum IM therapeutic doses caused no changes in PaO2, PaCO2 or pH, which would indicate clinically important ventilatory depression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1998

A multicentre double-blind comparison of hydroxyzine, buspirone and placebo in patients with generalized anxiety disorder.

The efficacy of hydroxyzine and buspirone, controlled by placebo, was investigated in a double-blind, parallel group, multicentre study conducted in France and the UK. A total of 244 patients with generalised anxiety disorder in primary care was allocated randomly to treatments with hydroxyzine (12.5 mg morning and mid-day, 25 mg evening), buspirone (5 mg morning and mid-day, 10 mg evening) or placebo (three capsules/day) for 4 weeks, preceded by a 1-week single-blind placebo run-in and followed by 1-week single-blind placebo administration. Rating scales were applied on days -7,0,7,14, 12,28 and 35. Seventy percent of the patients were female, the average age was 41 +/- 11 years, and the mean Hamilton Anxiety Score at day 0 was 26.5 +/- 4.2. Only 31 of the 244 patients dropped out, but equally in the three groups. Intention-to-treat LOCF analyses on the primary variable showed a significant difference only between hydroxyzine and placebo with respect to improvement on the Hamilton Anxiety Scale (10.75 versus 7.23 points, respectively). Secondary variables such as CGI and self-ratings (HAD scale) showed both hydroxyzine and buspirone to be more efficacious than placebo. Thus, hydroxyzine is a useful treatment for GAD.

Adolescent↗