Sequential randomised and double blind trial of promethazine prophylaxis against early anaphylactic reactions to antivenom for bothrops snake bites.
OBJECTIVE: To investigate the efficacy of the H1 antihistamine promethazine against early anaphylactic reactions to antivenom. DESIGN: Sequential randomised, double blind, placebo controlled trial. SETTING: Public hospital in a venom research institute, Sao Paulo, Brazil. PARTICIPANTS: 101 patients requiring antivenom treatment after being bitten by bothrops snakes. INTERVENTION: Intramuscular injection of promethazine (25 mg for adults and 0.5/kg for children) or placebo given 15-20 min before starting intravenous infusion of antivenom. MAIN OUTCOME MEASURES: Incidence and severity of anaphylactic reactions occurring within 24 hours after antivenom. RESULTS: Reactions occurred in 12 of 49 patients treated with promethazine (24%) and in 13 of 52 given placebo (25%); most were mild or moderate. Continuous sequential analysis indicated that the study could be interrupted at the 22nd untied pair, without preference for promethazine or placebo. CONCLUSION: Prophylaxis with promethazine does not prevent early reactions. Patients should be observed carefully during antivenom infusion and the subsequent few hours. (+info)
Comparison of oral chloral hydrate with intramuscular ketamine, meperidine, and promethazine for pediatric sedation--preliminary report.
Fifteen consecutive pediatric patients ranging from 3 to 5 years old were selected to receive one of three sedative/hypnotic techniques. Group 1 received oral chloral hydrate 50 mg/kg, and groups 2 and 3 received intramuscular ketamine 2 mg/kg and 3 mg/kg, respectively. In addition to ketamine, patients in groups 2 and 3 received transmucosal intramuscular injections of meperidine and promethazine into the masseter muscle. Sedation for the satisfactory completion of restorative dentistry was obtained for over 40 min on average in the chloral hydrate group, but completion of dental surgery longer than 40 min was achieved in groups 2 and 3 only by intravenous supplements of ketamine. (+info)
A double-blind, placebo-controlled investigation of the effects of fexofenadine, loratadine and promethazine on cognitive and psychomotor function.
AIMS: To assess whether fexofenadine in a range of doses from 80 to 180 mg has any disruptive effects on aspects of psychomotor and cognitive function in comparison with placebo, loratadine and promethazine, an antihistamine known to produce psychomotor and cognitive impairment. METHODS: Twenty-four healthy volunteers received fexofenadine 80 mg, 120 mg and 180 mg, loratadine 10 mg, promethazine 30 mg (as a positive internal control) and placebo in a six-way crossover, double-blind study. Following each dose, subjects were required to perform a series of tests of cognitive function and psychomotor performance at 1.5, 3, 6, 9, 12 and 24 h post dose. The test battery included critical flicker fusion (CFF), choice reaction time (CRT) and assessment of subjective sedation (LARS). Overall levels of activity were monitored by means of wrist mounted actigraphs throughout each of the 24 h experimental periods. RESULTS: Fexofenadine at all doses tested was not statistically different from placebo in any of the tests used and loratadine did not cause any significant impairment of cognitive function. Significant impairments were found following promethazine. Promethazine caused a significant reduction in CFF threshold and this effect was evident up to 12 h post dose (P<0.05). There was a significant increase in recognition reaction time at 3 and 6 h post promethazine administration, and the drug caused a significant (P<0. 002) increase in the percentage of 'sleep-like' activity from actigraph records during the daytime. CONCLUSIONS: Fexofenadine at doses up to 180 mg appears free from disruptive effects on aspects of psychomotor and cognitive function in a study where the psychometric assessments have been shown to be sensitive to impairment, as evidenced by the effects of the verum control promethazine 30 mg. (+info)
Efficacy of promethazine suppositories dispensed to outpatient surgical patients.
Postoperative nausea and vomiting frequently complicate outpatient anesthesia and surgery. The duration of treatment for this complication must occasionally extend beyond discharge from the hospital. In this study, we evaluated the commonly used anti-emetic promethazine for its efficacy in the post-discharge period. Adult outpatient surgical patients who had excessive postoperative nausea and vomiting in the recovery room, or who were at risk for postoperative nausea and vomiting following discharge were given two promethazine suppositories (25 mg) for home use. All patients were contacted by our recovery room nurses on the first business day after their surgery and questioned as to their use of the suppositories and, if used, their efficacy. We found that 55 percent of patients given promethazine suppositories for home use had nausea and vomiting in the post-discharge period. Of the patients given promethazine, 89 percent used the suppositories. All of these patients reported improvement in their symptoms following use of the suppositories. None reported adverse effects from the promethazine suppositories. In conclusion, we found promethazine suppositories to be an inexpensive and efficacious treatment for nausea and vomiting in adult outpatient surgical patients following discharge from the hospital. Side-effects were minimal, and our patients voiced no complaints about this mode of therapy. We recommend this therapy for treatment of nausea and vomiting after hospital discharge following adult outpatient surgery. (+info)
Metoclopramide and pimozide in Parkinson's disease and levodopa-induced dyskinesias.
Metoclopramide is an antiemetic drug which occasionally produced acute dystonic reactions. Although known to interfere with central dopamine mechanisms, it is frequently used in Parkinson's disease to prevent levodopa-induced nausea and vomiting. In this study metoclopramide did not increase Parkinsonism or reduce levodopa-induced involuntary movements in patients with Parkinson's disease. Pimozide, by contrast, increased Parkinsonism and reduced involuntary movements. The capacity of metoclopramide to produce acute dyskinesias while being apparently free of Parkinsonism effects is pharmacologically unique and differentiates this drug from the phenothiazines and butyrophenones. (+info)
An unusual multiple drug intoxication case involving citalopram.
A 47-year-old male with a history of drug abuse and suicide attempts was found dead at home. The death scene investigation showed evidence of cocaine abuse and multiple drug ingestion. Citralopram, a new selective serotonin reuptake inhibitor, cocaine, oxycodone, promethazine, propoxyphene, and norpropoxyphene were identified and quantitated in the postmortem samples by gas chromatography-mass spectrometry. The concentration of citalopram in the femoral blood was 0.88 mg/L. The heart blood concentration was 1.16 mg/L. Femoral blood concentrations of the other drugs were as follows: cocaine, 0.03 mg/L; oxycodone, 0.06 mg/L; promethazine, 0.02 mg/L; propoxyphene, 0.02 mg/L; and norpropoxyphene, 0.07 mg/L. Other tissue samples were also analyzed. The concentrations of cocaine, oxycodone, promethazine, and propoxyphene in the blood, liver, brain, and gastric contents did not suggest an intentional overdose. However, the possibility of multiple drug interactions including citalopram was evident. In this case, the citalopram concentrations were consistent with those reported in fatal cases involving multiple drug use. Citalopram was present in urine at a concentration of 0.9 mg/L. (+info)
A liquid chromatographic method for the simultaneous determination of promethazine and three of its metabolites in plasma using electrochemical and UV detectors.
A new assay method has been developed for the quantitation of promethazine (PMZ) with a sensitivity and reproducibility as good as any previously reported method. This method is also capable of quantitatively determining three metabolites of PMZ (monodemethylated, sulphoxidated, and monodemethylated sulphoxidated PMZ), which has not been previously described. The method uses high-performance liquid chromatography with amperometric and UV detection simultaneously and requires only one extraction step from serum with chloroform. The method uses trifluoperazine as the internal standard. The limit of detection level for PMZ is 1.0 ng/ml when a 0.2-mL specimen of plasma is assayed. A validation study is also conducted for evaluating the recovery, precision, linearity of response, sensitivity, and selectivity of the method. (+info)
Mechanistic appraisal of the charge-transfer complexes of promethazine with chloranil: a modelling approach.
Various mechanisms are often used to explain the interaction between electron donors and acceptors. Commonly proposed mechanisms are those in which the acceptor interacts with the aromatic pi-systems in the donor molecule or the acceptor forms a weak interaction of the Lewis acid with Lewis base type. In this study, the above mechanisms were examined as well as other possible mechanisms. Promethazine was chosen as the model drug containing aromatic systems capable of pi-pi interaction as well as N-methyl group capable of forming a complex with the weak Lewis acid, p-chloranil. Our modelling studies revealed that the situation where the p-chloranil interacts with a protonated N-methyl group is the most significant mechanism of interaction, based on the calculated energies for the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), the Tripos force field energy terms and also the stability of the complexes during molecular dynamics simulations. (+info)