Drugs for Autonomic Nervous System J. Arzaga, MSN, RN

Two Major Divisions of the Nervous System Central Nervous System (CNS) Brain and spinal cord Peripheral Nervous System All nervous tissue outside the CNS, including sensory and motor neurons J. Arzaga, MSN, RN

Basic Functions of the Nervous System Recognizing change Processing and integrating environmental change Reacting to environmental change J. Arzaga, MSN, RN

J. Arzaga, MSN, RN

J. Arzaga, MSN, RN

Autonomic Drugs Autonomic Nervous System –little disease Used to stimulate or inhibit target organs such as heart and lungs J. Arzaga, MSN, RN

Classification and Naming of Autonomic Drugs Adrenergic agents or sympathomimetics Stimulate sympathetic nervous system Adrenergic-blocking agents, adrenergic antagonists Inhibit sympathetic nervous system J. Arzaga, MSN, RN

Classification and Naming of Autonomic Drugs (cont'd) Cholinergic agents or parasympathomimetics Stimulate parasympathetic nervous system Cholinergic-blocking agents, anticholinergics Inhibit parasympathetic nervous system J. Arzaga, MSN, RN

Figure 13.3 Basic structure of the autonomic pathway

J. Arzaga, MSN, RN

J. Arzaga, MSN, RN

Prototype Drugs Phenylephrine (Neo-Synephrine) Adrenergic Agents (Sympathomimetics) Mechanism of action: to stimulate the sympathetic nervous system Primary use: Nasal congestion (intranasal) Opthalmic (topical) Acute Hypotension (IV)* Adverse effects: Increased BP J. Arzaga, MSN, RN

Prototype Drugs Atropine (Atro-pen, Atropair, Atropisol) Cholinergic-Blocking Agents Mechanism of action: to inhibit the parasympathetic nervous system, induce fight-or flight response Primary use: Dilate pupils Suppress secretions Bradycardia Adverse effects: increased HR,urinary retention, dry mouth, dry eyes, decreased sweating J. Arzaga, MSN, RN

Role of Nurse Monitor vital signs Monitor breathing patterns Monitor patient for abdominal distension, and auscultate for bowel sounds Monitor intake and output Provide comfort measures for dry mouth END. J. Arzaga, MSN, RN

Two Types of Adrenergic Receptors Alpha-receptors and Beta-receptors Hugely important to pharmacology Drugs are selective and activate only one type of adrenergic receptor, whereas others affect all receptor subtypes J. Arzaga, MSN, RN

Adrenergic Receptors In all sympathetic target organs except heart Alpha1-adrenergic Receptors Alpha2-adrenergic Receptors In all sympathetic target organs except heart Response Constriction of blood vessels Dilation of pupils At presynaptic adrenergic neuron terminals Activation inhibits release of norepinephrine J. Arzaga, MSN, RN

Adrenergic Receptors In heart and kidneys Response Beta1-adrenergic Receptors Beta2-adrenergic Receptors In heart and kidneys Response Activation increases heart rate and force of contraction of heart. Increases release of renin In all sympathetic target organs except the heart Inhibit smooth muscle J. Arzaga, MSN, RN

Role of Nurse Monitor patient’s condition Provide education on drug therapy Note adverse effects of drug therapy Identify possible interactions Identify contraindications of drug therapy Look at Nursing Process Focus pg. 134 J. Arzaga, MSN, RN

Role of Nurse Monitor for adverse effects Monitor liver enzymes Adrenergic Blocker Parasympathomimetics Monitor urinary hesitancy, incomplete bladder emptying, interrupted urinary stream Monitor vital signs, level of consciousness, and mood Monitor for dizziness, drowsiness, or light- headedness Observe for side effects Monitor cardiac output Monitor for adverse effects Monitor liver enzymes Calculate and monitor doses Assess and monitor for appropriate self-care administration J. Arzaga, MSN, RN

Role of Nurse Monitor intake and output ratio Direct Acting Cholinesterase Inhibitors Monitor intake and output ratio Monitor for blurred vision Monitor for orthostatic hypotension Monitor muscle strength and neuromuscular status Monitor ptosis, diplopia, and chewing Schedule medication around mealtimes Schedule activities to avoid fatigue Monitor for muscle weakness J. Arzaga, MSN, RN

Prototype Drugs Prazosin (Minipress) Adrenergic-Blocking Agents Mechanism of action: to inhibit the sympathetic nervous system Primary use: hypertension, dysrhythmias, angina, heart failure, benign prostatic hypertrophy, narrow-angle glaucoma Adverse effects: dizziness, drowsiness, headache, loss of energy and strength, palpitations, dry mouth J. Arzaga, MSN, RN

Prototype Drugs Bethanechol (Duvoid, Urecholine) Cholinergic Agents (Parasympathomimetic) Mechanism of action: to activate the parasympathetic nervous system directly/indirectly, induce rest/digest response Uses: glaucoma, urinary retention, myasthenia gravis, Alzheimer’s disease Adverse effects: profuse salivation, sweating increased muscle tone, urinary frequency, bradycardia J. Arzaga, MSN, RN