Cholinergic diagnosis

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. 

Diagnosis of my asthenia gravis IM 0.022 mg/kg. If CNS-cholinergic-myasthenia reaction occurs, discontinue tests and administer 0.4-0.6 mg or more atropine sulfate IV. Prevention of postoperative urinary retention IM, Subcutaneous 0.25 mg q4-6h for 2-3 days. 

How Alzheimer s disease kills cholinergic and other neurons leading to memory loss. Alzheimer s disease is still a pathological, not a clinical diagnosis. It is thus defined by the presence of abnormal degenerative structures seen postmortem in the neocortex,... 

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. 

The correct answer = D. The patient is exhibiting signs of cholinergic stimulation. Since he is a farmer, insecticide poisoning is a likely diagnosis. 

Cholinesterase inhibitor very short duration of action (15 minutes). Used in diagnosis of myasthenia gravis and to distinguish myasthenic crisis from cholinergic crisis. 

It is of particular utility in the diagnosis ofmyasthenia gravis. It may also be employed to make a clear distinction between a myasthenic crisis and a cholinergic crisis, because in the first instance an improvement of neuromuscular function is usually observed while in the second it worsens it further. 

The weakness occurs I -A days after a cholinergic crisis, with or without a symptom-free interval. Short relapses of muscarinic signs and symptoms do not exclude the diagnosis. 

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