Effect of a mixture of pyridostigmine and atropine on forced expiratory volume (FEV1), and serum cholinesterase activity in normal subjects.
Pyridostigmine 0.143 mg kg-1 (maximum 10 mg) and atropine 0.0143 mg kg-1 (maximum 1 mg) were administered i.v. to six healthy male volunteers. Peripheral venous blood samples were drawn for measurement of serum cholinesterase activity. Maximum inhibition of the enzyme was found 5 min after injection with a decrease to 27 +/- 5% (mean +/- SEM) of the original activity. Forced expiratory volume in the first 1s (FEV1) was measured at fixed time intervals for 90 min. No decrease in FEV1 was observed; on the contrary, there was a small increase. We conclude that atropine effectively antagonizes the muscarinic side-effects of pyridostigmine on bronchial smooth muscle tone and bronchial secretions, when administered in clinical doses to normal human subjects.
D000328:Adult; D001285:Atropine / Q000494:pharmacology*; D001980:Bronchi / Q000187:drug effects; D002802:Cholinesterases / Q000097:blood*; D004338:Drug Combinations; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D011729:Pyridostigmine Bromide / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D004338:Drug Combinations; D001285:Atropine; D002802:Cholinesterases; D011729:Pyridostigmine Bromide