Effects of bupropion on body weight.

Patients' weights were assessed during placebo-controlled, amitriptyline-controlled, and uncontrolled bupropion trials. Low-moderate (50-450 mg/day) to moderate-high (300-750 mg/day) doses of bupropion were consistently associated with a lack of weight gain (average weight loss of 1-2 pounds); placebo was associated with an average weight gain of 1 lb and 75-225 mg/day of amitriptyline was associated with an increase of 3-9 lb. Bupropion treatment was rarely accompanied by reports of appetite change and had no statistically significant effect on caloric intake when compared to placebo.

Single-dose single-point method in amitriptyline therapy.

Twenty-one depressed patients participated in a study that assessed the predictability of amitriptyline (AT) dosage based on plasma drug concentrations after a single dose. In 11 patients maintained on a fixed dose regimen, the 18-h single-dose level was confirmed to be predictive of steady-state levels. The dose for the next 10 patients was derived from their 18-h level aiming to attain steady-state levels of 200 ng/ml. The patients achieved a mean steady-state level of 213 ng/ml with 80% attaining therapeutic levels. All the patients improved within 2 weeks. These preliminary results suggest that dose prediction based on a single-dose TCA level is reliable and beneficial.

Monitoring tricyclic antidepressant plasma levels.

Patients receiving tricyclic antidepressants exhibit extreme variability in steady-state plasma concentrations because of differences in metabolism. At routine dosages, rapid metabolizers may have suboptimal concentrations while slow metabolizers can suffer from adverse effects due to inappropriately high concentrations. Neither may benefit from the drug therapy. Through analysis of plasma levels of tricyclic antidepressants, an optimal therapeutic response can be achieved, and the risk of serious side effects can be reduced.

Randomized, double-blind, placebo-controlled crossover trial of pirenzepine in patients with gastroesophageal reflux.

A muscarinic receptor subtype 1 (M1) antagonist, pirenzepine, recently has been shown to be relatively free of the usual anticholinergic side effects on esophageal smooth muscle and thus has been implicated for the treatment of gastroesophageal reflux disease (GERD). However, the effect of pirenzepine on GERD remains to be defined. Thirteen patients who demonstrated GERD in a baseline 24-hr ambulatory intraesophageal pH monitoring study were randomized in a double-blind crossover fashion to receive pirenzepine and placebo. An ambulatory 24-hr intraesophageal pH monitor was used to assess reduction in reflux (esophageal pH less than 4.0) with respect to position (upright vs supine), to total number of reflux episodes, and to episodes greater than 5 min. A significant effect for pirenzepine was seen for episodes greater than 5 min (t = 2.61, P = 0.023) and a trend towards significance was seen for total (upright and supine positions combined) percent time of reflux (t = 2.13, P = 0.055). Although not statistically significant, pirenzepine consistently showed greater reduction in all parameters of reflux tested. A greater reduction in percent time of reflux in supine vs upright positions (pirenzepine: 58.9% vs 21.4%; placebo: 43.6% vs 7.3%) may be clinically important in prevention of esophageal injury due to reflux in the recumbent position. Pirenzepine may provide a unique alternative for some GERD patients who may be refractory to other therapies of GERD.

Herpes zoster infection of the chest wall and the syndrome of inappropriate antidiuretic hormone secretion.

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) can result from diverse conditions. There have been only two published reports linking this syndrome with herpes zoster infections--one disseminated and the other confined to the chest wall. We have reported a case in which herpes zoster infection of the chest wall probably precipitated the development of this syndrome.