Multiple-dose activated charcoal for treatment of yellow oleander poisoning: a single-blind, randomised, placebo-controlled trial.

BACKGROUND: Deliberate self-poisoning with yellow oleander seeds is common in Sri Lanka and is associated with severe cardiac toxicity and a mortality rate of about 10%. Specialised treatment with antidigoxin Fab fragments and temporary cardiac pacing is expensive and not widely available. Multiple-dose activated charcoal binds cardiac glycosides in the gut lumen and promotes their elimination. We aimed to assess the efficacy of multiple-dose activated charcoal in the treatment of patients with yellow-oleander poisoning. METHODS: On admission, participants received one dose of activated charcoal and were then randomly assigned either 50 g of activated charcoal every 6 h for 3 days or sterile water as placebo. A standard treatment protocol was used in all patients. We monitored cardiac rhythm and did 12-lead electocardiographs as needed. Death was the primary endpoint, and secondary endpoints were life-threatening cardiac arrhythmias, dose of atropine used, need for cardiac pacing, admission to intensive care, and number of days in hospital. Analysis was by intention to treat. FINDINGS: 201 patients received multiple-dose activated charcoal and 200 placebo. There were fewer deaths in the treatment group (five [2.5%] vs 16 [8%]; percentage difference 5.5%; 95% CI 0.6-10.3; p=0.025), and we noted difference in favour of the treatment group for all secondary endpoints, apart from number of days in hospital. The drug was safe and well tolerated. INTERPRETATION: Multiple-dose activated charcoal is effective in reducing deaths and life-threatening cardiac arrhythmias after yellow oleander poisoning and should be considered in all patients. Use of activated charcoal could reduce the cost of treatment.

Prophylactic activity of atovaquone against Plasmodium falciparum in humans.

The prophylactic antimalarial activity of atovaquone was determined in a randomized, double-blind, placebo-controlled study of healthy volunteers who were challenged by the bite of Plasmodium falciparum-infected Anopheles stephensi. Subjects were randomly assigned to one of three groups: six received seven daily doses of 750 mg of atovaquone, starting the day before challenge; six received a single dose of 250 mg of atovaquone the day before challenge; and four received placebo. Polymerase chain reaction- and culture-confirmed parasitemia developed in all four placebo recipients, but in none of the drug recipients, indicating that either of the atovaquone regimens provides effective prophylaxis (P = 0.005). However, in low-dose recipients, the drug levels by day 6.5 were profoundly subtherapeutic, indicating that parasites were eliminated prior to the establishment of erythrocytic infection. Atovaquone thus protects non-immune subjects against mosquito-transmitted falciparum malaria, and has causal prophylactic activity.

In vivo effects of recombinant human DNase I on sputum in patients with cystic fibrosis.

BACKGROUND: Viscoelastic secretions in cystic fibrosis cause impaired mucus clearance and persistence of bacteria within the lung. The abnormal rheology is partly due to the presence of high molecular weight deoxyribonucleic acid (DNA). Recombinant human DNase I (rhDNase) has been shown to depolymerise DNA and thereby reduce the in vitro viscoelasticity of sputum in patients with cystic fibrosis. A phase II double blind placebo controlled study showed that rhDNase improved pulmonary function in patients with cystic fibrosis. The object of the present study was to evaluate the in vivo effects of rhDNase on sputum rheology and to determine whether these were correlated with changes in pulmonary function. METHODS: Patients were randomised to receive either placebo or rhDNase 2.5 mg twice daily for 10 days. Sputum samples were collected in sterile containers during screening and during treatment with the study drug. Pulmonary function and rheological analysis were the primary outcomes evaluated. Other parameters assessed were quantitative sputum bacteriology, sputum DNA concentration, and change in molecular mass of DNA polymers. RESULTS: The viscoelasticity of the sputum in untreated patients with cystic fibrosis was high and treatment with rhDNase reduced all the rheological parameters measured: dynamic storage modulus (a measure of elasticity), dynamic loss modulus (a measure of viscosity), and log complex modulus (a measure of mucus rigidity). The calculated cough clearance index was also improved following treatment with rhDNase. These rheological parameters showed a correlation with forced expiratory volume in one second (FEV1) which was improved by a mean (SE) of 13.3 (5.6)% on day 10 of treatment with rhDNase compared with a change of 0.2 (3.1)% in the placebo group. There was no change in bacterial colony counts or sputum DNA concentrations following treatment with rhDNase, but a small decrease in high molecular weight DNA was observed. CONCLUSIONS: Patients with cystic fibrosis treated with rhDNase show an improvement in rheological properties and pulmonary function, one of the mechanisms being a reduction in the proportion of high molecular weight DNA.

Efficacy and safety of short-term administration of aerosolised recombinant human DNase I in adults with stable stage cystic fibrosis.

Chronic pulmonary infection is the major cause of morbidity and mortality in cystic fibrosis. High levels of DNA in the sputum make the sputum viscous and difficult to expectorate. Recombinant human deoxyribonuclease (rhDNase) in vitro has been shown to reduce the viscoelasticity of the sputum from CF patients. We have done a phase II double-blind randomised placebo-controlled trial in which patients received either 2.5 mg rhDNase twice daily or placebo for 10 days. All patients had forced vital capacity (FVC) above 40% predicted and were clinically stable. Patients were followed up for 42 days from the start of drug/placebo administration. All 71 randomised patients, aged 16-55, completed every aspect of the study and baseline characteristics were similar in the two groups. Baseline forced expiratory volume in one second (FEV1) was 46% of predicted for patients randomised to rhDNase, and 48% for those randomised to placebo; and baseline FVC was 76% of predicted for both groups. The mean percentage change in FEV1 from baseline was a 13.3% rise on rhDNase and a 0.2% fall on placebo (p < 0.001). FVC rose 7.2% in the rhDNase group and 2.3% in the placebo group (not significant). There were no life-threatening adverse events and no anaphylactic reactions. There was no significant difference in side-effects between the groups. This study confirms that short-term administration of rhDNase in stable patients with cystic fibrosis is safe and improves lung function.