HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Correspondence: Submit a response Alert me when this article is cited Alert me when Correspondence are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by White, M. C. Articles by Havard, C. W. H. Search for Related Content PubMed PubMed Citation Articles by White, M. C. Articles by Havard, C. W. H.

Plasma pyridostigmine levels in myasthenia gravis

From the Department of Medicine, Royal Free Hospital, London, England.

Plasma concentrations of pyridostigmine were measured after oral administration in 16 patients with myasthenia gravis. The levels varied greatly among both well- and poorly controlled patients, but were usually higher in the latter group. Absorption of the drug appears to be erratic; its clearance from the plasma is slow and its metabolism could involve an enterohepatic circulation. Drugs such as methylcellulose may prevent absorption. Three poorly controlled patients were studied on a high-dose alternate-day steroid regimen, and a marked decrease in pyridostigmine bioavailability on the same dose of drug was observed in all three. No such changes were demonstrated in a volunteer group taking a lower dose of steroids.

Address correspondence and reprint requests to Dr. Havard, Department of Medicine, Royal Free Hospital, London NW3, England.

Accepted for publication April 21, 1980.