Drugs Affecting the Central & Autonomic Nervous System

Flashcards covering the Autonomic Nervous System, including SNS and PNS receptors, agonists, and antagonists as presented in the NUR 1290 lecture notes.

Autonomic Nervous System

A division of the peripheral nervous system that regulates involuntary body functions, consisting of the parasympathetic (cholinergic) and sympathetic (adrenergic) systems.

Parasympathetic Nervous System (PNS)

Known as the 'Rest & Digest' response; functions include constricting pupils (miosis), slowing the heartbeat, constricting bronchi, and stimulating digestion, salivation, and bladder contraction.

Sympathetic Nervous System (SNS)

Known as the 'Fight or Flight' response; functions include dilating pupils (mydriasis), accelerating heartbeat, dilating bronchi, inhibiting digestion, and stimulating glucose release.

Neurotransmitters

Chemical substances that make it possible for messages to be transmitted by crossing a synapse, exciting or inhibiting a physiological response.

$$\alpha_1\text{ Receptors}$$

Adrenergic receptors that cause vasoconstriction, decreased GI and bladder motility, mydriasis, decreased secretions, and glycogenolysis when activated.

$$\alpha_2\text{ Receptors}$$

Receptors located on the presynaptic nerve that inhibit the sympathetic nervous system response.

$$\beta_1\text{ Receptors}$$

Adrenergic receptors primarily located in the heart that increase heart rate, contraction, and conduction when stimulated.

$$\beta_2\text{ Receptors}$$

Adrenergic receptors that cause bronchodilation, uterine relaxation, and decreased GI motility when activated.

Dopaminergic Receptors

Receptors that respond to dopamine to increase blood flow to the brain, heart, kidneys, and viscera; high doses cause vasoconstriction.

Muscarinic Receptors

Cholinergic receptors that, when activated, increase GI and bladder motility, increase secretions, constrict pupils (miosis), and decrease heart rate.

Agonist

A drug or substance that binds to a receptor and activates a physiological response.

Antagonist

A drug or substance that blocks or inhibits receptor activation.

Sympathomimetics

Adrenergic agonist drugs that mimic the actions of norepinephrine, epinephrine, and dopamine on receptors.

Albuterol (Ventolin)

A $\beta_2$ adrenergic agonist used for bronchodilation in respiratory conditions like asthma and bronchitis.

Phenylephrine (Neo-Synephrine)

An $\alpha_1$ adrenergic agonist used for nasal congestion and as a vasoactive agent for cardiovascular support.

Epinephrine (Adrenalin)

A catecholamine used for emergency treatment of anaphylactic shock and in ophthalmic applications to cause mydriasis.

Midodrine (ProAmatine)

An adrenergic agonist drug specifically used to treat hypotension.

Sympatholytics

Adrenergic antagonist drugs that 'lyse' or inhibit sympathetic nervous system stimulation by blocking adrenergic receptors.

Doxazosin (Cardura)

An $\alpha_1$ blocker used to treat hypertension by causing arterial and venous dilation.

Tamsulosin (Flomax)

An $\alpha_1$ blocker used to treat benign prostatic hyperplasia (BPH) by decreasing resistance to urinary outflow.

Phentolamine (Regitine)

A potent vasodilator used to treat tissue necrosis resulting from the extravasation of IV alpha adrenergics.

Propranolol (Inderal)

A non-selective beta blocker with high lipophilicity that enters the CNS easily, used for migraine headaches and cardiovascular issues.

Parasympathomimetics

Cholinergic agonist drugs that mimic the neurotransmitter acetylcholine (ACh) to produce a 'Rest and Digest' response.

Bethanechol (Urecholine)

A direct-acting cholinergic agonist indicated for urinary retention and GI or bladder atony.

Pyridostigmine (Mestinon)

An indirect-acting cholinergic indicated for the treatment of Myasthenia gravis.

SLUDGE

An acronym for cholinergic crisis toxicity: Salivation, Lacrimation, Urinary incontinence, Diarrhea, GI cramps, and Emesis.

Anti-cholinergics (Parasympatholytics)

Drugs that competitively block the action of acetylcholine at muscarinic receptors, leading to increased HR, bronchodilation, and decreased secretions.

Atropine (AtroPen)

An anti-cholinergic drug used to treat bradycardia and heart blocks.

Dicyclomine (Bentyl)

An anti-cholinergic drug indicated for the treatment of irritable bowel syndrome and diarrhea.

Oxybutynin (Ditropan)

An anti-cholinergic drug used to manage incontinence and neurogenic bladder.

Glycopryrolate (Robinul)

An anti-cholinergic drug used to reduce secretions in the mouth, nose, pharynx, and bronchi during surgery or the common cold.