E G Antal | PubMed Health

PubMed1987

Diuretic actions in man of a selective kappa opioid agonist: U-62,066E.

The effect of a selective kappa opioid agonist, U-62,066E, on urine formation in human volunteers was assessed. Volunteers received single intramuscular injections of either placebo or 2, 3, 4, 5 or 6 micrograms/kg of U-62,066E in a randomized, double-blind study. U-62,066E caused dose-dependent maximal increases in urine volume of 2.6 times control in the first 4 hr after administration. A corresponding decrease in urine osmolality to 20% of base-line values occurred. No changes in total urinary Na, K or Cl excretion were identified. Kappa agonists produce a water-only diuresis at low doses in humans. The mechanism of this effect was not examined in this study but probably relates to alterations in antidiuretic hormone activity.

Adolescent↗

PubMed1981

Audit of phenytoin prescribing for outpatients.

Phenytoin prescribing for outpatients was audited to determine if it had any deficiencies and to identify the incidence of toxicity. A pharmacy audit committee developed process and outcome criteria for phenytoin prescribing. The retrospective audit involved 45 patients (age, 14-72 years) who had regular contact with a seizure clinic for a two-year period. Only one unjustified therapeutic variation existed according to the criteria outlined for the audit. The incidence of phenytoin toxicity was approximately 38%, but all of the patients received acceptable clinical management.

Ambulatory Care↗

PubMedDate not supplied

Ibutilide: a new class III antiarrhythmic agent.

Ibutilide fumarate is a new antiarrhythmic agent recently approved for the conversion of atrial flutter (AFl) and atrial fibrillation (AF) to normal sinus rhythm. A class III agent in the Vaughan Williams classification system, ibutilide prolongs cardiac repolarization by activating a slow inward, predominantly sodium current. An alternative or additive mechanism to prolong repolarization may be blockade of the outward delayed rectifier potassium rapid current. Ibutilide is administered intravenously, and approximately 40% of the drug in serum is protein bound. It is eliminated through hepatic metabolism by undefined enzyme systems, and it appears that none of the metabolites contributes significantly to antiarrhythmic activity. The elimination half-life of ibutilide ranges from 2-12 hours. When administered by 10-minute infusion, ibutilide 1 mg (approximately 0.015 mg/kg) resulted in conversion to sinus rhythm in 24-58% of patients with AFl and 20-32% with AF, compared with about 5% for placebo. Administering a second dose of 0.5-1 mg improved the overall response rates to approximately 75% and 45%, respectively. In randomized comparative trials, ibutilide was more effective than sotalol in converting AFl (70% vs 19%) and AF (44% vs 11%) and more effective than procainamide (76% vs 12% and 51% vs 20%, respectively). The time to conversion in most trials was usually 20-30 minutes. Nausea is the most common noncardiac adverse effect (< 2%). Nonsustained and sustained polymorphic ventricular tachycardia occurred in 2.7-6.7% and 1.7% of patients, respectively.

Animals↗