Adrenergic & Cholinergic Drugs Flashcards
All tissues within the body, except skeletal muscles, are innervated by what?
Autonomic nervous system (Sympathetic or Parasympathetic)
Sympathetic discharge causes…
Increased CO (increased HR & contractility)
Decreased visceral blood flow, increased skeletal blood
Peripheral vasoCONSTRICTION
Increased cellular metabolism
Bronchial RELAXATION (decreased resistance)
Parasympathetic discharge causes…
Slowed heart rate and contractility
Increased digestion/absorption
Peripheral vasoDILATION
Bronchial CONSTRICTION (increased resistance)
Neurotransmitters involved in ANS
Acetylcholine
Epinephrine & Norepinephrine (SNS - released from adrenal medulla)
Cholinergic receptors include:
Nicotinic & Muscarinic receptors
Adrenergic receptors include:
Alpha-1, Alpha-2, Beta-1, Beta-2 & Beta-3
Cholinergic Stimulants
Direct - Bind to cholinergic receptors & activate them
Indirect - Increase activity at synapses by inhibiting acetylcholinersterase enzyme (enzyme that destroys ACh)
What kind of conditions are Cholinergic Stimulants used to treat?
Alzheimer Disease, GI/Bladder issues, Glaucoma, Myasthenia Gravis, & Neuromuscular blockages
Adverse Effects of Cholinergic Stimulants
GI distress, increased salivation, bronchoCONSTRICTION, bradycardia, difficulty with visual accomodation, & increased sweating
What are Anti-Nicotinic (Anti-cholinergic) Drugs used for?
Hypertension, Block skeletal NMJ (anesthesia)
What are Anti-Muscarinic (Anti-cholinergic) Drugs used for?
Gi disorders (IBS), Parkinson’s, Cardiovascular issues (Atropine), Motion sickness, Preoperative medications, UTI, RTI, and pupil dilation
Anticholinergic Side Effects
Can’t see, Can’t pee, Can’t poo
Blurry vision, Urinary Retension, & Constipation
Dry mouth, Tachycardia, Confusion, Dizziness, Nervousness & Drowsiness
Alpha-1 Selective Agonists
Bind directly to alpha-1 on smooth muscle receptors to activate them and cause vasoCONSTRICTION & CONTRACTION)
Treat: Hypotension, nasal congestion, and SVT by decreasing heart rate and constricting vasculature in upper respiratory mucosa
Side Effects of Alpha-1 Agonists
Increased Blood Pressure
Headache
Decreased Heart Rate
Chest Pain
Difficulty Breathing
Nervousness
Alpha-2 Selective Agonists
Bind directly to alpha-2 receptors at CNS synapses (Brain/SC)
Treat: Hypertension & spasticity
Side Effects of Alpha-2 Agonists
Dizziness, drowsiness, dry mouth, difficulty breathing, unusually slow HR, fainting
Toxicity or overdose
Beta-1 Selective Agonists
Bind to beta-1 receptors on myocardium and cause increased HR and myocardial contractility
Treat: Emergency situations and short term CHF requiring increased CO
Side Effects of Beta-1 Agonists
Chest pain, cardiac arrhythmias, SOB, and difficulty breathing
Beta-2 Selective Agonists
Bind to beta-2 receptors on bronchiole smooth muscle to cause relaxation and DILATION
Treat: Spasm and constriction associated with Asthma, Bronchitis, and Emphysema
Bronchodilator example: Ventolin
Side Effects of Beta-2 Agonists
Nervousness, restlessness & trembling
Mixed Alpha/Beta Agonists
Stimulate both receptors and cause nervous system excitability.
Examples: Epinephrine & ephedrine
Side Effects of Mixed Alpha/Beta Agonists
Restlessness, Anxiety, HTN & Arrhythmias
What are Adrenergic Antagonists referred to as?
Sympatholytic drugs – Block receptors that would normally cause sympathetic responses
Alpha Antagonists
Reduce peripheral vascular tone - Cause VASODILATION by blocking receptors. Primarily used to treat HTN by reducing peripheral vascular resistance
Beta Antagonists
Decrease contractility of the heart and decrease heart rate by blocking receptors. Used to treat HTN, arrhythmias, angina pectoris, s/p MI, CHF
Cardioselective only bind to beta-1 receptors
What occurs if a drug is not selective for beta or alpha receptors?
May bind to both receptor types and cause bronchoconstriction along with increased heart rate
What occurs if a drug is not selective for beta or alpha receptors?
May bind to both receptor types and cause bronchoconstriction along with increased heart rate
Adverse effects of Alpha Antagonists
Reflex Tachycardia (compensation for when BP drops)
Orthostatic Hypotension (dizziness & syncope)
Adverse effects of Beta Antagonists
Respiratory distress (when nonselective)
Excessive depression of cardiac function
Orthostatic Hypotension
Depression, Lethargy, Sleep Disorders
Blunted HR response to exercise
