Effects of nifedipine therapy on pulmonary Raynaud's in primary Sjögren's syndrome.

A case of Raynaud's phenomenon of the pulmonary vascular bed in Primary Sjögren's syndrome and subsequent response to calcium channel blockade is presented. Pulmonary Raynaud's phenomenon in Primary Sjögren's syndrome has not been previously described.

Rapid and sustained oral theophylline loading. An alternative to intravenous aminophylline therapy.

We evaluated an oral theophylline loading-dose procedure that was designed to rapidly achieve and sustain theophylline serum concentrations of approximately 10 to 12 micrograms/mL. Ten healthy adults were given an oral loading dose of approximately 6 mg/kg of aminophylline, (Aminophyllin) (ie, 4.8 mg/kg of theophylline). Two hours later, each subject was given approximately 6 mg/kg of a sustained-release theophylline tablet (Theo-Dur). Serum samples were collected at 1/2, 1, 2, 3, 6, 9, and 12 hours, then assayed for theophylline concentration. The mean theophylline concentration (+/- SD) one hour after the initial loading dose was 10.5 +/- 2.3 micrograms/mL. Subsequent theophylline concentrations demonstrated minimal fluctuation, with means ranging from 10.7 +/- 1.6 to 13.6 +/- 2.8 micrograms/mL. Four of the subjects reported headache; none vomited or experienced severe nausea. We conclude that this method of oral theophylline loading can be effective in achieving prompt and sustained therapeutic theophylline levels without significant side effects and that this may provide a valuable therapeutic alternative in those asthmatic patients who do not clearly require intravenous aminophylline therapy.

The effect of erythromycin on theophylline pharmacokinetics at steady state.

We compared steady-state theophylline pharmacokinetics in 13 healthy adults before and immediately after erythromycin therapy. All subjects received a five-day course of oral aminophylline 3 mg/kg every six hours prior to and during a five-day course of oral erythromycin stearate (1 g daily). Each subject acted as his own control. Multiple serum samples were collected over ten hours following the last dose of aminophylline during both the control and experimental phases of the study. Erythromycin did not significantly affect theophylline clearance (P greater than 0.70), elimination (P greater than 0.75), or volume of distribution (P greater than 0.30). We found no evidence of a pharmacokinetic interaction between theophylline and erythromycin at steady state. Worsening pulmonary function may be responsible for altered theophylline pharmacokinetics in patients coincidentally receiving erythromycin.