PHA 101: Adrenergic and Cholinergic

Flashcards about Adrenergic and Cholinergic Agonists and Antagonists

Adrenergic Agonists

Stimulate sympathetic nervous system; mimic neurotransmitters norepinephrine and epinephrine; act on adrenergic receptor sites.

Alpha1 receptors

Increases vasoconstriction, blood pressure, bladder relaxation, and prostate contraction.

Beta1 receptors

Increases cardiac contractility and heart rate; increases blood pressure.

Beta2 receptors

Bronchodilation; increases blood glucose.

Epinephrine Action

Increases blood pressure; increases heart rate; promotes bronchodilation.

Epinephrine Uses

Anaphylaxis, anaphylactic shock; bronchospasms; cardiac arrest.

Epinephrine Side effects/adverse reactions

Cardiac dysrhythmias, palpitations; tachycardia, hypertension; dizziness, headache, sweating; insomnia, restlessness, tremors; hyperglycemia.

Adrenergic Antagonists

Block effects of adrenergic neurotransmitter by occupying receptors directly or inhibiting release of neurotransmitters epinephrine and norepinephrine indirectly.

Beta1 Antagonists

Reduces cardiac contractility; decreases heart rate.

Beta2 Antagonists

Bronchoconstriction; contracts uterus; inhibits glycogenolysis (leads to hypoglycemia).

Nonselective beta blockers

Decrease BP and heart rate, but can cause Bronchoconstriction; use with caution in patients with COPD or asthma.

Selective beta blockers

Blocks beta1 only, decreasing BP and HR with fewer side effects.

Cholinergic Agonists

Drugs that stimulate PNS; mimic parasympathetic neurotransmitter acetylcholine.

Muscarinic receptors

Affect smooth muscles, slow heart rate.

Nicotinic receptors

Affect skeletal muscles.

Cardiovascular effects of Cholinergic Agonists

Decrease HR and BP, vasodilation, slow conduction of AV node.

GI effects of Cholinergic Agonists

Increase tone, motility, peristalsis, and relax sphincter muscles.

GU effects of Cholinergic Agonists

Increase ureter tone, contract bladder and relax sphincter muscles, stimulate urination.

Eye effects of Cholinergic Agonists

Constrict pupils, increase accommodation.

Lungs effects of Cholinergic Agonists

Bronchial constriction, increase secretions.

Glands effects of Cholinergic Agonists

Increase salivation, perspiration, and tears.

Direct-Acting Cholinergic Agonists (Bethanechol chloride)

Primarily selective to muscarinic receptors in smooth muscles; used to increase urination.

Bethanechol Side effects/adverse reactions

Hypotension; increased salivation and gastric acid; diarrhea.

Heart effects of anticholinergics

Large doses increase HR.

Lungs effects of anticholinergics

Bronchodilation, decrease secretions.

GI effects of anticholinergics

Relax smooth muscle tone, decrease motility and peristalsis, decrease secretions.

GU effects of anticholinergics

Relax bladder muscle, increase sphincter constriction.

Eye effects of anticholinergics

Dilate pupils, decrease accommodation.

Exocrine glands effects of anticholinergics

Decrease salivation and perspiration.

Atropine Action

Increase heart rate; decrease salivary and gastric secretions.

Atropine Side effects/adverse reactions

Dry mouth, decreased sweating; tachycardia, pupil dilation, blurred vision; urinary retention, constipation.

Atropine Contraindications

Contraindicated in glaucoma.