EDROPHONIUM is used in the diagnosis of myasthenia gravis.

NEOSTIGMINE, PYRIDOSTIGMINE, and ambenonium are used in the treatment of myasthenia gravis.

There are no therapeutic uses for the irreversible cholinesterase inhibitors.

PRALIDOXIME and ATROPINE are used to treat poisoning with organophosphates.

The prototypic muscarinic antagonist is ATROPINE.

All of the muscarinic antagonists are competitive antagonists for the binding of acetylcholine to the muscarinic receptor.

Muscarinic antagonists are used preoperatively to reduce secretions.

SCOPOLAMINE is used to prevent motion sickness.

IPRATROPIUM is used in the treatment of chronic obstructive pulmonary disease
(COPD) to produce bronchodilation.

Muscarinic antagonists are used for urinary frequency, urgency, and urge incontinence caused by bladder (detrusor) overactivity.

The competitive neuromuscular blocking drugs are used to produce skeletal muscle relaxation.

SUCCINYLCHOLINE is a depolarizing neuromuscular blocker.

Notice that most of the drug names contain the letters “-cur-”. This should make it easier to recognize the drugs in this group when you see them.

Botulinum toxin blocks the release of acetylcholine at all cholinergic synapses.

DANTROLENE is used to treat malignant hyperthermia.

Only EPINEPHRINE and NOREPINEPHRINE activate both α and β receptors.

NOREPINEPHRINE has a relatively low affinity for β2 receptors.

The main effect of α1 stimulation (with an agonist such as phenylephrine) is vasoconstriction.

At low doses, DOPAMINE causes renal and coronary vasodilation. It also activates β1 receptors in the heart.