A double-blind, placebo-controlled study of the efficacy and safety of non-prescription ranitidine 75 mg in the prevention of meal-induced heartburn

BACKGROUND: Ranitidine 75 mg (Zantac 75) has been shown to be effective for the treatment of pre-existing heartburn symptoms. AIM: To compare the efficacy of dosing ranitidine 75 mg or placebo 30 min prior to a proven heartburn-provoking meal in completely preventing or reducing subsequent heartburn symptoms. METHODS: A randomized, double-blind, parallel methodology was used at nine investigative centres. Following a screening visit, patients ate a standard test meal consisting of chili, chips and a soft drink on two occasions. On the first occasion, patients received single-blind placebo 30 min before the meal. This meal was used to qualify patients and to ensure the onset of a minimum level of heartburn. Patients who qualified were randomized (n = 284) to receive double-blind ranitidine 75 mg or placebo 30 min before a second test meal administered 4-14 days later at the treatment visit. Patients recorded whether heartburn was present and rated heartburn severity by completing visual analogue scales at 15-min intervals over the 4. 5 h meal evaluation periods. RESULTS: Statistically significant differences favouring ranitidine 75 mg were determined for complete prevention of heartburn (P < 0.006), heartburn severity area under the curve (P < 0.001), a clinical success end-point (P < 0.001), and all other end-points (P < 0.001). CONCLUSIONS: These data clearly demonstrate that ranitidine 75 mg is effective in completely preventing or decreasing heartburn when administered 30 min prior to a provocative meal.     

GR 38032F (Ondansetron), a selective 5HT3 receptor antagonist,slows colonic transit in healthy man

The newly recognized class of 5-hydroxytryptamine receptors (5HT₃) may be involved in the induction of nausea, since their pharmacological antagonists are effective against emesis induced by chemotherapy. 5HT₃ receptors are present on enteric neurons, and 5HT₃ blockers may produce mild constipation; we thus hypothesized that 5HT₃ receptors would modulate colonic motility. To determine if GR 38032F, a selective 5HT₃ antagonist known to have antiemetic effects, influences colonic transit in health, a randomized, double-blind, placebo-controlled crossover study was performed. Using a radiopaque marker technique, colonic transit was quantified in 39 healthy volunteers (19 men, 20 nonpregnant women) 18–70 years of age. On a standard 25-g fiber diet, 16 mg of GR 38032F was given orally thrice daily. Gastrointestinal peptides (peptide YY, human pancreatic polypeptide, neurotensin, motilin, gastrin-cholecystokinin, substance P) were also measured in plasma fasting and postprandially. Mean total colonic transit time on placebo was 27.8 hr, while on GR 38032F it was 39.1 hr (P<0.0005). Transit times through the left colon (P<0.0005) and rectosigmoid (P<0.05) were prolonged by the drug, but right colonic transit was not significantly altered. Transit times did not correlate with age or gender, but subjects with shorter transit times were significantly more affected than were those with longer transit times. The peak release of peptide YY was minimally decreased following GR 38032F (P<0.01), but the peak and integrated postprandial responses of human pancreatic polypeptide, neurotensin, motilin, gastrin-cholecystokinin, and substance P were not significantly altered by the drug. We conclude that 5HT₃ receptors may be involved in the regulation of colonic transit in healthy man.Supported in part by a grant from Glaxo Group Research, Ltd., and the Mayo Digestive Disease Center (grant DK34988, National Institutes of Health, Bethesda, Maryland).Presented, in part, at the American Motility Socicty in October 1988, and published as an abstract inGastroenterology 95:891, 1988.     

Prevalence and correlates of dyslipidemia in HIV positive and negative adults in Western Kenya: A cross-sectional study

There is increasing morbidity and mortality from cardiovascular diseases (CVD) in sub-Saharan Africa (SSA). Dyslipidemia is a well-known CVD risk factor which has been associated with human immunodeficiency virus (HIV) infection and its treatment in high-income countries. Studies in SSA that have examined the relationship between HIV and dyslipidemia have reported mixed results. In this study, we sought to determine the prevalence of dyslipidemia in HIV positive and negative adults (>=30 years old) and evaluate for association in Western Kenya with a higher prevalence expected among HIV positive individuals.HIV positive adults receiving antiretroviral therapy (ART) and HIV negative individuals seeking HIV testing and counseling services were recruited into a cross-sectional study. Demographic and behavioral data and fasting blood samples were collected. Dyslipidemia was defined according to the National Cholesterol Education Program Adult Treatment Panel III. Associations between baseline demographic and clinical variables and dyslipidemia were analyzed using logistic regression.A total of 598 participants, 300 HIV positive and 298 HIV negative adults were enrolled. Dyslipidemia data was available for 564 (94%) participants. In total, 267 (47%) had dyslipidemia. This was not significantly different between HIV positive and HIV negative individuals (46% vs 49%, P = .4). In a multivariate analysis including both HIV positive and negative individuals, adults 50 to 59 years of age had a 2-fold increased risk of dyslipidemia (Odds ratio [OR] 2.1, 95% confidence interval (1.2–3.5) when compared to 30 to 39-years-old participants. Abdominal obesity (OR 2.5), being overweight (OR 1.9), and low fruit and vegetable intake (OR 2.2) were significantly associated with dyslipidemia. Among HIV positive participants, time since HIV diagnosis, ART duration, use of (PI) protease inhibitor-based ART, viral load suppression, current cluster of differentiation (CD4) count and nadir CD4 did not have significant associations with dyslipidemia.The prevalence of dyslipidemia is high in Western Kenya, with nearly half of all participants with lipid abnormalities. Dyslipidemia was not significantly associated with HIV status, or with HIV-specific factors. Older age, being overweight, abdominal obesity, and low fruit and vegetable intake were associated with dyslipidemia and may be targets for public health interventions to lower the prevalence of dyslipidemia and CVD risk in sub-Saharan Africa.     

In vitro bactericidal effect of Nd:YAG laser on Actinomyces israelii

A bactericidal effect has been reported by the use of near-infrared laser light on both Gram-positive and Gram-negative bacteria. The aim of this study was to evaluate the effect of Nd:YAG laser on Actinomyces israelii, filamentous bacteria causing cervicofacial actinomycosis. Experiments were realized on bacterial cells in saline suspension or streaked on Mueller–Hinton (MH) agar plates with or without India ink. Laser application was performed in Eppendorf tubes with different powers and frequencies for 40 s; bacterial suspensions were then streaked on agar plates and incubated at 35 °C in proper conditions for 5 days before colony enumeration. A reduction of colony number variable from 60.13 to 100 % for powers of 2, 4, and 6 W at 25–50 Hz of frequency was observed in comparison with growth control. For agar plates, laser application was performed with different powers at 50 Hz for 60 s. A growth inhibition was observed after 5 days of incubation on MH plates with powers of 6 W and on MH–ink plates with all applied powers. This preliminary study showed a bactericidal effect caused by Nd:YAG laser application worthy to be evaluated in further experiments in vivo.     

Ranitidine, 75 mg, over-the-counter dose: pharmacokinetic and pharmacodynamic effects in children with symptoms of gastro-oesophageal reflux

BACKGROUND: The use of over-the-counter antacids has increased in children under the age of 12 years, and has been followed by an apparent increase in the use of over-the-counter histamine-2 receptor antagonists. However, the pharmacokinetic and pharmacodynamic effects of over-the-counter histamine-2 receptor antagonists in the paediatric population are largely unknown. AIM: To evaluate the pharmacokinetics and pharmacodynamics of a single dose of the over-the-counter histamine-2 receptor antagonist, ranitidine, 75 mg, in children with symptoms of gastro-oesophageal reflux disease. METHODS: Children aged between 4 and 11 years with symptoms of heartburn suspected to be due to gastro-oesophageal reflux disease were recruited at six clinical centres. Following a single dose of either oral ranitidine, 75 mg (n=19), or placebo (n=10), recording of intragastric pH and serial blood sampling were carried out for 6 h. RESULTS: The estimated pharmacokinetic parameters of ranitidine, 75 mg, were as follows: the median Cmax value of 477 ng/mL occurred within a median of 2.5 h after dosing, and the median half-life was 2.0 h. The intragastric pH began to rise approximately 30 min after dosing with ranitidine to a peak of pH; 4. The pH in the ranitidine group remained higher than that in the placebo group throughout the 6-h evaluation period. Adverse events were generally mild. CONCLUSIONS: Ranitidine, 75 mg, significantly increased the intragastric pH in children aged 4-11 years. The pharmacokinetic and pharmacodynamic profiles were similar to those in adults. Ranitidine, 75 mg, appears to be effective for the control of intragastric acidity for 5-6 h in children aged 4-11 years.     

Social Media and Mental Health Among Early Adolescents in Sweden: A Longitudinal Study With 2-Year Follow-Up (KUPOL Study)

PurposeThe aim of this study is to assess the longitudinal associations between the frequency of social media use and symptoms of mental ill-health among Swedish adolescents.MethodsData came from KUPOL, a Swedish school-based longitudinal cohort accrued in 101 participating schools in 8 regions of Sweden. The study sample consisted of 3,501 adolescents in grade 8 (14–15 years, 51.5%, n = 1,765 girls) followed for 2 consecutive years. Daily social media use was measured as weighted average of self-reported use in weekdays and weekend days. Mental health was measured with the Strength and Difficulties Questionnaire (SDQ). A Random-Intercept Cross-Lagged Panel Model was applied to distinguish between-person from within-person associations between social media use and symptoms of mental ill-health.ResultsMedian SDQ score at baseline was 9 (interquartile range [IQR] 6–14). Median social media use was 1.7 hours at baseline (interquartile range .6–3.0) and increased over the 3-year period. Adolescents with more social media use also reported higher SDQ scores, B (95% confidence interval [CI]) = 2.40 (2.03–2.77). On a within-person level, no cross-lagged associations were found between changes in social media use and subsequent changes in symptoms of mental ill-health after 1 year, B (95% CI) = .02 (?.12 to .16) or vice versa B (95% CI) = .00 (?.02 to .02). Weak cross-sectional associations were found between changes in social media use and concurrent changes in symptoms of mental ill-health, B (95% CI) = .24 (.00–.48).ConclusionsAdolescents with higher use of social media report more symptoms of mental health problems, but there is no evidence for a longitudinal association between increased use and mental health problems. This suggests that social media may be rather an indicator than a risk factor for symptoms of mental ill-health.     

A single-blind study of doxazosin in the treatment of mild-to-moderate essential hypertensive patients with concomitant noninsulin-dependent diabetes mellitus

Doxazosin, a selective α₁-inhibitor, was assessed for antihypertensive efficacy, effect on lipid parameters, and safety profile in 21 hypertensive patients with noninsulin-dependent diabetes mellitus. The study involved a 2- to 4-week baseline period, a 10-week period in which patients received doxazosin, 1 to 8 mg, once daily, and a 4-week maintenance period. All 16 of the efficacy evaluable patients (100%) had their blood pressure controlled (sitting diastolic blood pressure ≤90 mm Hg) at a mean dose of 3.6 mg once daily. For efficacy evaluable patients mean sitting blood pressure was significantly (p < 0.05) reduced by $\text{26}\text{17}\text{mm Hg}$ at the final visit. Five patients each reported a single side effect and none was severe. No patients required dose reduction or discontinuation of therapy because of side effects. No clinically significant laboratcry changes were apparent, and no trends were observed with regard to organ systems or correlations with dose or duration of treatment. The investigators' global assessment of efficacy of once-daily doxazosin therapy was excellent or good for 15 patients and fair for six patients. The overall assessment of patient toleration was excellent or good for 19 patients, fair for one, and not reported for one. High-density lipoprotein cholesterol was significantly increased (p = 0.03). From baseline to final visit, there was a highly significant reduction of 30% (p < 0.005) in calculated coronary heart disease risk score on the basis of the Framingham equation.