Pyridostigmine myasthenia gravis

Myasthenia gravis is a disease tiiat involves rapid fatigue of skeletal muscles because of die lack of ACh released at die nerve endings of parasympathetic nerve fibers. Drugs used to treat this disorder include ambeno-nium (Mytelase) and pyridostigmine (Mestinon). 

The answer is a. (Hardman, pp 161-169.) Although all of the listed compounds inhibit the activity of the cholinesterases, only edrophonium chloride is used in the diagnosis of myasthenia gravis. The drug has a more rapid onset of action (1 to 3 min following intravenous administration) and a shorter duration of action (approximately 5 to 10 min) than pyridostigmine... 

Apart from neostigmine, pyridostigmine and ambenonium are the other standard drugs used in the treatment of myasthenia gravis. 

Pyridostigmine Mestinon Myasthenia gravis, reversal of neuromuscular blocking drugs... 

The therapeutic uses of neostigmine include the treatment of atony of the urinary bladder and postoperative abdominal distention. In addition, it antagonizes the action of rf-tubocurarine and curariform drugs. Edrophonium, neostigmine, or pyridostigmine may be used to diagnose myasthenia gravis. Because edrophonium has the shortest duration of action, it is most often used for this purpose. 

Pyridostigmine [peer id doe STIG meen] is another cholinesterase inhibitor that is used in the chronic management of myasthenia gravis. Its duration of action (3-6 hours) is longer than that of neostigmine (2-4 hours). 

PROPAFENONE PARASYMPATHOMIMETICS 1 efficacy of neostigmine and pyridostigmine Uncertain propafenone has a degree of antinicotinic action that may oppose the action of parasympathomimetic therapy for myasthenia gravis Watch for poor response to these parasympathomimetics and t dose accordingly... 

The pharmacologic treatment of myasthenia gravis is based on increasing the amount of available acetylcholine by use of oral cholinesterase inhibitors such as neostigmine or pyridostigmine. Pyridostigmine bromide (Mestinon) is used most often and effectively relieves myasthenic symptoms in small muscles innervated by cranial nerves, particularly those involved in ptosis. 

For myasthenia gravis, both to diagnose (edrophonium) and to treat (neostigmine, pyridostigmine, distigmine) To stimulate the bladder and bowel after surgery (bethanechol, carbachoi, distigmine)... 

Pyridostigmine is similar to neostigmine but has a less powerful action that is slower in onset and slightly longer in duration, and perhaps fewer visceral effects. It is used in myasthenia gravis. 

Severe urticaria and anaphylaxis associated with pyridostigmine (an unspecified dose) occurred in a 54-year-old woman with myasthenia gravis (9). Urticaria started almost immediately after introduction of the drug but was partially controlled by the antihistamine cetirizine. However, pyridostigmine was stopped after 2 months and the urticaria resolved completely. Rechallenge with oral pyridostigmine led to an anaphylactic reaction that was treated with subcutaneous adrenaline. There were no sequelae. 

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