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Results for “randomized crossover trial”

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At least 361 records · Page 20Linked to original sources

PubMed1990

[A new inhalation system for bronchodilatation. Study of the acceptance of the Ingelheim M inhaler in chronic obstructive respiratory tract diseases].

The aim of this study was to investigate the acceptance and convenience of a new inhalation system for the treatment of chronic obstructive pulmonary disease. The Ingelheim M inhalator, an inhalation system with a supply magazine for six powder-filled capsules represents a further development of the Ingelheim inhalator in which only a single capsule can be utilized. The study was designed as an open, randomized, crossover trial involving 60 ambulatory adult patients. Each treatment period lasted two weeks. The medication tested was Berodual Inhaletten. The success of treatment was checked on the basis of peak flow metering each morning prior to and after initial inhalation. The results of the study show a highly significant preference on the part of the patients for the new inhalation system. The advantage most emphasized by the patients was the fact that they were able to carry with them their entire daily dose. Differences in the symptomatology of chronic obstructive pulmonary disease were not observed with these inhalation systems.

Adolescent↗

PubMed1987

Biosynthetic human insulin improves postprandial glucose excursions in type I diabetics.

To determine if the more rapid absorption of subcutaneously administered human insulin, as compared with animal insulin, would result in an improved postprandial metabolic response, ten persons with type I diabetes mellitus were studied during a fixed meal. Plasma glucose and insulin concentrations were compared after subcutaneous injections of 0.2 U/kg body weight of regular biosynthetic human insulin or regular purified pork insulin in a double-blind randomized crossover trial. Meal glycemic excursions improved after the administration of biosynthetic human insulin, when compared with purified pork insulin (p less than 0.05 at 150, 180, and 210 minutes postprandially). Serum free immunoreactive insulin concentrations were significantly higher after injections of biosynthetic human insulin, and the rate of incremental rise during the first 30 minutes was also greater. Insulin antibody studies showed a strong negative correlation between peak insulin levels and the association constant for the high-affinity-binding insulin antibodies. We conclude that biosynthetic human insulin is more rapidly absorbed after subcutaneous injection than is purified pork insulin, a characteristic that results in improved postprandial metabolic control.

Absorption↗

PubMed1997

Lack of effect of estrogen on rest and treadmill exercise in postmenopausal women without known cardiac disease.

To assess the peripheral vascular effects of estrogen in women without coronary disease, normal postmenopausal women (mean age 56 +/- 8 years) participated in a randomized, crossover trial using treadmill exercise echocardiography, and received oral conjugated estrogen, 0.625 mg/day or underwent a drug-free period. There was no significant effect on heart rate, blood pressure, double product, left ventricular end-systolic and end-diastolic diameters, or electrocardiographic measures after estrogen. In contrast to the profound effects reported in patients with cardiac disease, oral estrogen in normal women does not bestow significant benefit on treadmill exercise echocardiographic variables at rest or during modest levels of exercise.

Adult↗

PubMed1989

[Piroxicam versus naproxen in primary dysmenorrhea].

In this study 198 patients with primary dysmenorrhea were entered into a double-blind, randomized crossover trial to study the efficiency of piroxicam compared to naproxen on menstrual pain and associated symptoms. The dosage for piroxicam was 40 mg on the first and second day of the menstrual cycle, and if necessary an additional 20 mg on the third day. The dosage for naproxen was 1,000 mg on the first and second day, and if necessary an additional 500 mg on the third day. Piroxicam and naproxen afforded high relief from menstrual pain and associated symptoms. The drugs were well tolerated with only a few side effects of a mild nature. There were no statistically significant differences between piroxicam and naproxen.

Adolescent↗

PubMed1988

Sorbitol catharsis does not enhance efficacy of charcoal in a simulated acetaminophen overdose.

The use of a 70% sorbitol solution has recently been advocated as an adjunct to activated charcoal. This results in rapid and profuse catharsis that could possibly cause fluid and electrolyte imbalance. An investigation was undertaken to determine if sorbitol catharsis enhanced the antidotal efficacy of activated charcoal. Eight healthy volunteers participated in a randomized, crossover trial. Subjects ingested 3 g of acetaminophen followed by either no intervention, 50 g of plain activated charcoal at one hour, or 50 g activated charcoal-sorbitol solution at one hour. Serial acetaminophen levels were determined at intervals over eight hours and side effects noted. Both interventions significantly reduced the area under the curve versus control (P less than .05). The addition of sorbitol did not enhance the efficacy of activated charcoal but did increase the side effects noted. Sorbitol has not been proven effective in enhancing drug removal and has side effects that can be significant in a poisoned patient. Current data do not warrant its use, and further investigations should be carried out with other ingested drugs.

Acetaminophen↗

PubMed1984

Low-dose metoclopramide versus methylprednisolone in controlling chemotherapy induced nausea and vomiting.

Ninety outpatients with histologically confirmed malignancy receiving chemotherapy entered a randomized crossover trial to assess the antiemetic efficacy of low-dose metoclopramide versus methylprednisolone. Treatment consisted of either metoclorpramide (MCP) 60 mg or methylprednisolone (MPN) 375 mg administered in 3 equal doses just prior to chemotherapy and 6 and 12 hours after treatment. Patients receiving MPN had significantly less nausea (p less than 0.001) and fewer episodes of vomiting (p less than 0.0003) than patients receiving MCP. MPN also proved to be the more effective agent in cross-over trials. Both MPN and MCP were well tolerated. No important side effects were observed. MPN is a safe, effective, antiemetic treatment suitable for use in the outpatient.

Adult↗

PubMed1984

The diltiazem-digoxin interaction.

To study the interaction between the calcium antagonist diltiazem and digoxin, a randomized crossover trial under steady-state conditions was carried out in 24 healthy male subjects. Diltiazem with digoxin induced an average increase of steady-state plasma digoxin concentration and AUC over 48 hr of 22.4%. This is caused by the prolongation of elimination t1/2 from 36.2 +/- 11.2 to 44.5 +/- 11.5 hr (means +/- SD) and the impairment of total digoxin clearance, dropping from 146.6 +/- 37.9 to 107.9 +/- 18.4 ml/min. Average reduction in renal clearance (from 102.1 +/- 35.5 to 85.5 +/- 42.7 ml/min) was not statistically reproducible. Apparent volume of distribution was not relevantly altered. Diltiazem kinetics did not change significantly when digoxin was concurrently given.

Adult↗

PubMed1989

Cryosurgery versus dilation and massage for the treatment of recurrent urethral syndrome.

One year after the initiation of a prospective, randomized, crossover trial comparing dilation and massage to urethral cryosurgery utilizing a specially designed urethral cryoprobe, our results show that cryosurgery was more effective in the treatment of recurrent urethral syndrome in women. Ninety-one percent of patients first treated with cryosurgery were successful in achieving relief from their symptoms whereas only 33% of the women initially treated with dilation and massage were successful (P = .005). In addition, cryosurgery was more successful in treating women when they crossed over after failing the other therapy (75% vs. 0%). In total, 21 of 24 patients (87.6%) were treated successfully with one of the two modalities. Nineteen of the 22 patients (86.4%) in this select group treated with cryosurgery during the trial were successful, whereas only 5 of 15 (33.3%) treated with dilation and massage were successful (P = .001).

Cryosurgery↗

PubMed1979

A double-blind crossover comparison of pindolol, metoprolol, atenolol and labetalol in mild to moderate hypertension.

1 This study was designed to compare in a double-blind randomized crossover trial, atenolol, labetalol, metoprolol and pindolol. Considerable differences in dose (atenolol 138 +/- 13 mg daily; labetalol 308 +/- 34 mg daily; metoprolol 234 +/- 22 mg daily; and pindolol 24 +/-2 mg daily were required to produce similar antihypertensive effects. 3 The overall incidence of side-effects was similar with atenolol, metoprolol and pindolol but was slightly less with labetalol. Sleep disturbances and abnormal dreaming patterns were most frequent with pindolol. 4 There was a significantly greater fall in pulse rate during atenolol and metoprolol treatment periods.

Adrenergic beta-Antagonists↗

PubMed1979

Comparison of metoprolol and pindolol in the treatment of mild to moderate hypertension: a double-blind crossover study.

Matched doses of metoprolol and pindolol were administered to 31 hypertensive outpatients in a double-blind randomized crossover trial, which was designed to compare the antihypertensive efficacy and pattern of side effects of the two drugs. Twenty-nine patients completed the study. A tenfold difference in dose (25 +/- 2 mg/day of pindolol and 234 +/- 22 mg/day of metoprolol) was required to produce a similar antihypertensive effect. There was a significantly greater fall in pulse rate during metoprolol treatment. Complaints of dry mouth, mild Raynaud's phenomenon, and eye discomfort were more frequent during treatment with metoprolol; and sleep disturbances and abnormal dreaming patterns were more frequent during treatment with pindolol.

Adult↗

PubMed2002

Impact and modulation of nasal obstruction.

Nasal obstruction, the leading symptom of allergic rhinitis, results from the combined activity of early- and late-phase allergic reactions. Desloratadine inhibits both early- and late-phase inflammatory mediators in vitro. Thus, double-blind, placebo-controlled, randomized, crossover trials were conducted to assess the efficacy of desloratadine against nasal obstruction, measured objectively and subjectively, during controlled exposure of patients with seasonal allergic rhinitis to allergen. Positive results were obtained in three single-dose studies; desloratadine 5 mg resulted in a greater improvement from baseline than did placebo in the total symptom score and the nasal obstruction symptom score (P </= 0.02). Desloratadine was more effective than placebo in a multiple-dose study; desloratadine 5 mg was given once daily for 7 days, and a 6-h allergen challenge was administered at the end of treatment compared with placebo. Desloratadine treatment was associated with less deterioration from baseline in the mean nasal airflow (P < 0.05) and in the mean severity score for the symptom of nasal obstruction (P < 0.03). Desloratadine significantly reduces the severity of nasal obstruction in patients with seasonal allergic rhinitis.

Histamine H1 Antagonists↗

PubMed1986

Transdermal nitroglycerin as a step 3 antihypertensive drug.

The antihypertensive effect of transdermal nitroglycerin was tested in 11 men with hypertension (mean age 60 years) whose diastolic blood pressure exceeded 90 mm Hg while receiving a diuretic and a beta-adrenergic blocker. In a double-blind, randomized crossover trial the subjects received weekly increments of placebo or nitroglycerin (5, 10, 20, and 30 cm2) for 4 weeks each. The final dose of nitroglycerin was 22.5 cm2 (mean). During week 4 of nitroglycerin dosing, sitting and standing systolic blood pressures were reduced (P less than 0.05). Diastolic blood pressures and heart rates did not change during the study. In the five subjects with systolic hypertension (greater than or equal to 150 mm Hg), the mean reduction in systolic blood pressure was 24 mm Hg (P less than 0.01). Further studies are needed to determine if transdermal nitroglycerin has a role in the treatment of systolic hypertension.

Administration, Topical↗

PubMed1989

Ferrous sulfate reduces levodopa bioavailability: chelation as a possible mechanism.

This study examined the effect of ferrous sulfate, a widely used iron treatment, on levodopa bioavailability in normal subjects. A 250 mg tablet of levodopa was taken with and without a 325 mg tablet of ferrous sulfate by eight normal subjects in a randomized crossover trial. When levodopa was taken with ferrous sulfate there was a 55% decrease in peak levodopa levels (3.6 +/- 2.6 vs 1.6 +/- 0.82 nmol/ml; p less than 0.05) and a 51% decrease in AUC (257 +/- 133 vs 125 +/- 51 nmol.min/ml; p less than 0.01). Persons with the highest peak levodopa levels and AUC after levodopa alone had the greatest reduction in peak levodopa levels and AUC after levodopa ingestion with ferrous sulfate. Iron in its ferrous state is oxidized rapidly to the ferric state in the presence of levodopa at pHs found in the small intestine. In the ferric state, iron binds very strongly to levodopa. Chelation of iron by levodopa is the likely mechanism for this drug interaction. The clinical significance of this interaction is yet to be established.

Adult↗

PubMed1999

The effect of ketoconazole on the pharmacokinetics, pharmacodynamics and safety of nisoldipine.

OBJECTIVE: The primary aim of the present study was to investigate the effect of ketoconazole on the pharmacokinetics of nisoldipine. METHODS: A single dose of nisoldipine 5 mg immediate-release tablet was administered either alone or in combination with ketoconazole 200 mg (4 days pretreatment and concomitant administration) in a randomized crossover trial in seven healthy male Caucasian volunteers. Plasma concentration-versus-time profiles of nisoldipine and its metabolite M9 were determined. RESULTS: Pre-treatment with and concomitant administration of ketoconazole resulted in a 24-fold and 11-fold, increase in mean AUC and Cmax of nisoldipine, respectively, compared with treatment with nisoldipine 5 mg alone. The ketoconazole-induced increase in plasma concentration of the metabolite M9 was of similar magnitude. CONCLUSION: The interaction is attributed to inhibition of cytochrome 3A4-mediated first-pass metabolism. Ketoconazole and other antifungal drugs of the substituted imidazole type as well as other potent inhibitors of cytochrome 3A4 should not be used concomitantly with nisoldipine.

Adult↗

PubMed1985

Activity-sensing, rate-responsive pacing: improvement in myocardial performance with exercise.

A sensor that detects body activity by low frequency sonic impulses has been incorporated in a pacemaker so that body activity may be translated to an increased pacing rate in response to exercise. The pacemaker is designed for patients who may benefit from an increased cardiac output mediated by an increased heart rate during exercise. Following permanent pacemaker implantation, six patients (mean age 69 years) entered a single blind, randomized, crossover trial for comparison of activity-sensing, rate-responsive pacing (A) to fixed rate demand pacing (D). Ventricular function was assessed by gated radionuclide ventriculography at rest and at exercise, while exercise capacity was assessed by treadmill performance, along with measurements of oxygen consumption and carbon dioxide production. Total treadmill duration and maximum oxygen consumption were similar in the two pacing modes (A = 284 +/- 244 s, 13.4 +/- 3.4 ml O2/min/kg; D = 256 +/- 250 s, 11.7 +/- 3.7 ml O2/min/kg). Anaerobic threshold, however, was significantly improved (A = 266 +/- 199 s, (p less than .05), 13.0 +/- 2.2 ml O2/min/kg (p less than .01); D = 231 +/- 208 s, 10.8 +/- 2.3 ml O2/min/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Pharmacokinetics of clarithromycin extended-release (ER) tablets in patients with AIDS.

BACKGROUND: Clarithromycin is a key agent in effective antimycobacterial therapy and prophylaxis for AIDS-related disseminated Mycobacterium avium complex (dMAC) infection. Immediate-release (IR) clarithromycin tablets are dosed at 500 mg bid for these indications. A new extended-release (ER) tablet of clarithromycin has been developed and approved at a dosing interval of once every 24 hours for treatment of respiratory tract bacterial infections. However, the pharmacokinetics of clarithromycin ER in AIDS patients with or at risk for dMAC has not been previously investigated. METHOD: We conducted a randomized, crossover trial in which 14 AIDS patients received clarithromycin ER, 1000 mg once daily, and clarithromycin IR, 500 mg bid, each for 1 week, with pharmacokinetic sampling at the end of each week. RESULTS: The mean of the individual AUC ratios for clarithromycin ER vs. IR was 1.09 (90% CI, 0.94-1.24). Adverse events were no more severe or frequent with clarithromycin ER than IR. CONCLUSION: Clarithromycin ER is a once-daily regimen that is as well tolerated as standard bid IR clarithromycin dosing and has average bioequivalence to the IR formulation in patients with AIDS.

Acquired Immunodeficiency Syndrome↗

PubMed1985

Evaluation of an extension set for intermittent intravenous drug delivery to infants.

An intravenous administration set designed for delivery of drug doses to pediatric patients was tested in vitro for the effect of fluid density and flow rate on drug delivery, and delivery of drug by this extension set was compared in vivo with delivery by other methods. Gentamicin (as the sulfate salt) and penicillin G potassium were used to represent low-density and high-density drugs, respectively; a 1-mL solution of each drug, labeled with carbon 14, was tested with each of two primary infusion solutions: 0.45% sodium chloride injection and 10% dextrose injection. The drug dose was injected via a port into a piston-containing chamber from which an equivalent amount of the primary fluid was displaced. Serial samples collected from the end of the filter-containing extension set were analyzed for drug concentration using a liquid scintillation technique. In 12 infants receiving i.v. gentamicin, this delivery method was compared in a randomized crossover trial with delivery by a syringe pump and by i.v. push. Each delivery system was used on one of three consecutive days, and serum gentamicin concentrations were measured by enzyme-multiplied immunoassay. The time required for in vitro delivery of the dose was dependent on flow rate. Density of the drug solution or the primary i.v. fluid did not significantly affect drug delivery. Serum gentamicin concentrations were not significantly different for the three delivery methods, but variability of drug delivery was greatest with the pediatric extension set. This pediatric extension set provides accurate and reliable drug delivery at primary infusion flow rates slower than 10 mL/hr when the drug dosage volume is 2-3 mL or less.

Evaluation Studies as Topic↗

PubMed2006

Sex differences in the hemodynamic responses to mental stress: Effect of caffeine consumption.

The effect of caffeine on stress responses was compared in 25 men and 22 women in a 2-week placebo-controlled, double-blind, randomized crossover trial. On each week, participants abstained from all dietary sources of caffeine before undergoing a 6-h laboratory protocol under placebo or caffeine exposure followed by a 30-min mental stressor with blood pressure (BP) and cardiovascular hemodynamic assessments. On the placebo session, men and women showed a significant BP increase to stress, although women had significant cardiac responses whereas men had vascular responses. Caffeine ingestion before stress caused both men and women to have enhanced hemodynamic responses to the stressor associated with an increase in cardiac index and a drop in the peripheral resistance index. Caffeine enhances the cardiovascular fight-or-flight response pattern to stress in men and women.

Adult↗