Myasthenia gravis diagnosis

Trade names Enlon (Baxter) Tensilon (Valeant) Indications Myasthenia gravis diagnosis Category Anesthetic Cholinesterase inhibitor Half-life 1.8 hours... 

Myasthenia gravis diagnosis and treatment, paralytic ileus, atony of detrusor of bladder, reversal of neuromuscular blockade following anesthesia. 

Myasthenia gravis diagnosis, treatment of excess tubocurarine to reverse neuromuscular blockade. 

The cholinesterase inhibitor that is used in the diagnosis of myasthenia gravis is... 

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... 

Differential Diagnosis With single cases, rather than clearly epidemic cases, the illness could be confused with Guillain-Barre syndrome, myasthenia gravis, or tick paralysis. Other possible considerations may include enteroviral infections, as well as nerve agent and atropine poisoning. 

Mechanism of Action A parasympathetic, anticholinesterase agent that inhibits destruction of acetylcholine by acetylcholinesterase, thus causing accumulation of acetylcholine at cholinergic synapses. Results in an increase in cholinergic responses such as miosis, increased tonus of intestinal and skeletal muscles, bronchial and ureteral constriction, bradycardia, and increased salivary and sweat gland secretions. Therapeutic Effect Diagnosis of myasthenia gravis. 

Diagnosis of myasthenia gravis IV 2-mg test dose over 15-30 sec. If no reaction in 45 sec, give additional dose of 8 mg. Test dose maybe repeated after 30 min. IM/SC Initially, 10 mg as a single dose. If no cholinergic reaction occurs, give 2 mg 30 minutes later to rule out false-negative reaction. 

Edrophonium Alcohol, binds briefly to active site of acetylcholinesterase (AChE) and prevents access of acetylcholine (ACh) Amplifies all actions of ACh increases parasympathetic activity and somatic neuromuscular transmission Diagnosis and acute treatment of myasthenia gravis Parenteral quaternary amine does not enter CNS Toxicity Parasympathomimetic excess Interactions Additive with parasympathomimetics... 

In the treatment of wide-angle glaucoma In the diagnosis of myasthenia gravis... 

The actions of edrophonium [ed roe FOE nee um] are similar to those of neostigmine, except that it is more rapidly absorbed and has a short duration of action (10-20 minutes). Edrophonium is a quarternary amine and is used in the diagnosis of myasthenia gravis. Intravenous injection of edrophonium leads to a rapid increase in muscle strength. Care must be taken since excess drug may provoke a cholinergic crisis. Atropine is the antidote. 

An office test shown to be of value for supporting a diagnosis of ocular myasthenia gravis, particularly if ptosis is present, is the ice-pack test. The test is based on the premise that neuromuscular transmission improves at lower temperatures. An ice pack is applied to the affected eye for 1 to 2 minutes, and the eye is observed to see whether the ptosis improves. 

In addition, several autoimmune reactions to penicillamine can secondarily affect pulmonary function. PeniciUamine-induced polymyositis (56) or myasthenia gravis can cause respiratory failure, even requiring ventilatory support (57). The diagnosis and management of lupus-induced pleurisy have been reviewed (58). 

The methylsulfate salt is used posloperativcly as a urinary stimulant and in (he diagnosis and treatment of myasthenia gravis. 

A patient presents with a complaint of muscle weakness following exercise. Neurological examination reveals that the muscles supplied by cranial nerves are most affected. You suspect myasthenia gravis. Your diagnosis is confirmed when lab tests indicate antibodies in the patient s blood against... 

Edrophonium is an anticholinesterase muscle stimulant that facihtates myoneural junction impulse transmission by inhibiting acetylcholine destmction by cholinesterase. It is indicated in differential diagnosis of myasthenia gravis as an adjunct in evaluating treatment of myasthenia gravis in evaluation of aner-gency treatment of myasthenic aises in reversal of neuromuscular blockade by curare gallamine or tubo-curarine and in treatment of respiratory depression caused by curare overdose. 

Edrophonium is very short-acting, so is not used for treatment. Its major uses are in diagnostic procedures, such as the diagnosis of myasthenia gravis. It is also used to reverse the effects of competitive neuromuscular blockade (e.g., d-tubocurarine) after surgery. 

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