Learning objectives
In this lecture, you’ll learn:
• classes of drugs that affect the autonomic nervous system
• uses and actions of these drugs
• absorption, distribution, metabolization, and excretion of these dru
• drug interactions and adverse reactions to these drugs.
,Drugs and the autonomic
nervous system
The autonomic nervous system regulates the body’s involuntary
functions, including heart rate, respiratory rate, and digestion. It wor
through a balance of its two main components, the sympathetic and
parasympathetic nervous systems. Types of drugs used to treat
disorders of the autonomic nervous system include:
• cholinergic drugs
• anticholinergic drugs
• adrenergic drugs
• adrenergic blocking drugs.
,Cholinergic drugs
Cholinergic drugs promote the action of the neurotransmitter acetylcholine. These drugs a
also called para sympathomimetic drugs because they produce effects that imitate
parasympathetic nerve stimulation.
Mimic or inhibit
There are two major classes of cholinergic drugs:
• Cholinergic agonists mimic the action of the neurotransmitter acetylcholine.
• Anticholinesterase drugs work by inhibiting the destruction of acetylcholine at cholinergic
receptor sites. (See How cholinergic drugs work.)
Cholinergic agonists
• By directly stimulating cholinergic receptors, cholinergic agonists mimic the action of the
neurotransmitter acetylcholine. They include such drugs as:
• acetylcholine (not to be confused with the neurotransmitter)
• bethanechol
• carbachol
• pilocarpine.
, Pharmacokinetics (how drugs circulate)
The action and metabolism of cholinergic agonists vary widely and depend on th
affinity of the individual drug for muscarinic or nicotinic receptors. For example,
drug acetylcholine poorly penetrates the central nervous system (CNS), and its
effects are primarily peripheral, with a widespread parasympathetic action.
The drug is rapidly destroyed in the body. Pilocarpine, on the other hand, binds
muscarinic receptors and stimulates smooth muscles in the urinary tract, bronch
and biliary and intestinal tracts.
The “eyes” (and the mouth, and the skin) have it!
Cholinergic agonists are usually administered:
• topically, with eyedrops
• orally
• by subcutaneous (subcut) injection. Subcut injections begin to work more
rapidly than oral doses.
In this lecture, you’ll learn:
• classes of drugs that affect the autonomic nervous system
• uses and actions of these drugs
• absorption, distribution, metabolization, and excretion of these dru
• drug interactions and adverse reactions to these drugs.
,Drugs and the autonomic
nervous system
The autonomic nervous system regulates the body’s involuntary
functions, including heart rate, respiratory rate, and digestion. It wor
through a balance of its two main components, the sympathetic and
parasympathetic nervous systems. Types of drugs used to treat
disorders of the autonomic nervous system include:
• cholinergic drugs
• anticholinergic drugs
• adrenergic drugs
• adrenergic blocking drugs.
,Cholinergic drugs
Cholinergic drugs promote the action of the neurotransmitter acetylcholine. These drugs a
also called para sympathomimetic drugs because they produce effects that imitate
parasympathetic nerve stimulation.
Mimic or inhibit
There are two major classes of cholinergic drugs:
• Cholinergic agonists mimic the action of the neurotransmitter acetylcholine.
• Anticholinesterase drugs work by inhibiting the destruction of acetylcholine at cholinergic
receptor sites. (See How cholinergic drugs work.)
Cholinergic agonists
• By directly stimulating cholinergic receptors, cholinergic agonists mimic the action of the
neurotransmitter acetylcholine. They include such drugs as:
• acetylcholine (not to be confused with the neurotransmitter)
• bethanechol
• carbachol
• pilocarpine.
, Pharmacokinetics (how drugs circulate)
The action and metabolism of cholinergic agonists vary widely and depend on th
affinity of the individual drug for muscarinic or nicotinic receptors. For example,
drug acetylcholine poorly penetrates the central nervous system (CNS), and its
effects are primarily peripheral, with a widespread parasympathetic action.
The drug is rapidly destroyed in the body. Pilocarpine, on the other hand, binds
muscarinic receptors and stimulates smooth muscles in the urinary tract, bronch
and biliary and intestinal tracts.
The “eyes” (and the mouth, and the skin) have it!
Cholinergic agonists are usually administered:
• topically, with eyedrops
• orally
• by subcutaneous (subcut) injection. Subcut injections begin to work more
rapidly than oral doses.
