Pharmacology Introduction Ace Inhibitors
Gina Maiocco, PhD, RN, CCRN, CCNS Reduce arterial pressure by preventing generation of angiotensin II from
angiotensin I
Key Terms Angiotensin II = potent vasoconstrictor
Agonist Causes: B/P, water retention (aldosterone)
– A drug that has an affinity for the cellular receptors of another drug or natural Ace Inhibitors: (I.e. captopril, enalapril, lisinopril)
substance that – B/P
produces an physiological effect – renal perfusion
Antagonist
– A drug that binds to a cellular receptor for a hormone, neurotransmitter, or another
Angiotensin II Inhibitors
Block the binding of angiotensin II to specific tissue receptors in vascular smooth
drug
muscle &
blocking the action of that substance without producing any physiologic effect itself.
adrenal glands
“Blocking Agent” Produces:
Key Terms – B/P
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Adrenergic Example
– Sympathetic NS – Losartin (cozaar)
Cholenergic
– Parasympathiometic application CNS & Drugs
Dopaminergic
– Dopamine involvement in CNS regulation
Cholinergic Effects
Parasympathetic nervous system
Key Terms – Acetylcholine (ACh) is primary neurotransmitter
Alpha = vasoconstriction – Nicotinic receptors: HR, B/P, peripheral vasoconstriction
Beta = muscle activity – Muscarinic receptors: gastric motility, gastric acid & salivary secretion
– B1 = myocardium = contraction, HR Conditions treated
– B2 = bronchial & vascular smooth muscles = bronchial relaxation and arterial dilation – Alzheimers, Parkinson’s dx, motion sickness, PUD, IBS, visual disorders, urinary
to retention
skeletal muscles
Chronotrope
Direct Acting Cholinergics
– Affects rate Structurally similar to Ach
Inotrope Example:
– Affects force of muscular contraction by activating beta cells – Urecholine
– Treats postoperative or postpartum urine retention
Cardiovascular Applications – Causes contraction and emptying of bladder
– Side effects
Adrenergic Effects Abdominal cramps
Sympathetic NS - agent that acts like epinephrine Salivation
Produces: N/v & diarrhea
– Vasoconstriction
– HR, BP, CO Cholinesterase Inhibitor (colinergic)
Blocking agents Elevates acetycholine concentrations in cerebral cortex by slowing degradation by
– peripheral vasodilation cholinesterase
– HR, B/P Elevated levels of ACh slows the neuronal degradation seen in Alzhiemer’s.
2 Example:
Specific Drugs Imparting Adrenergic Effects – Aricept (donepezil)
– Side effects: abdominal pain, diarrhea, GI bleed
Alpha Agents Anticholinergics
Alpha = vasoconstriction Reverse cholinergic (parasympathetic) effects
Alpha adrenergic agonist Blocks ACh at receptor sites in smooth muscles, secretory glands, SA & AV nodes
– Norepinephrine (levophed) & cardiac
– Action = B/P, work of heart muscle
Blocking agent - competes with catecholamines at peripheral autonomic receptor Example
sites – Scopolamine – motion sickness
– Regitine = dilation of arteries and veins – Atropine
– Treat dopamine infiltration sites (see tissue necrosis) – Treatment for bradycardia, excess secretions (preop)
– Side effect = orthostatic hypotension
Beta Adrenergic Agents Dopaminergic Drugs
Dopamine is a CNS neurotransmitter
Dobutamine or Dopamine (5 –10 mcg) 4
– force of contraction, heart rate Action
– Conditions: shock, CHF, sepsis – Inhibits excitatory signals produced by ACh
Beta adrenergic antagonist - beta blockers (propanolol, labetalol) dopamine produces cholinergic activity
– HR, force of contraction – Tremors (pill rolling)
– Conditions: AMI, HPT – Rigidity (involuntary contraction of muscles)
Calcium Channel Blockers – Bradykinesia – general slownes
– Akinesia – loss of voluntary movement
Calcium enhances muscle depolarization (resting potential)
calcium = b/p, arrhythmias, angina, migraines Parkinson’s Disease
Ca+ = B/P, rest Extensive deterioration of neurons at basal ganglia – see dopamine levels
Example: Combo therapy
– Verapamil – Dopaminergic Drugs
– Cardiazem – Levodopa
Precursor to dopamine
– Anticholinergic Drugs
– Cogentin
– Artane
Pain and More Pain
Opioids - analgesics
Tx moderate to severe pain by crossing blood brain barrier
Effects: Anti-inflammatory effect – reduced mucus secretion in respiratory conditions
– CNS - LOC Uses:
– Respiratory depression – Asthma, COPD, SCI
– Cardiovascular Example: flovent, solumedrol, azmacort, decadron
– Orthostatic hypotension Side Effects
– GI - GI muscle tone – Mask Infections
– GU – urinary retention – Hyperglycemia
Opioid Terms – Slow wound healing
Opioid agonist Beta Agonists
– Produce maximal response (schedule II drugs) Relieve bronchoconstriction
– Examples: codeine, morphine, demerol, oxycodone Uses
Opioid agonist-antagonist – Short term – tx acute exacerbations
– Activate opioid receptor without causing respiratory depression – Long term – control symptoms, especially nocturnal
– Example: stadol, nubain, talwin Examples: alupent, serevent, proventil
Opioid antagonist Side effects
– Blocks or reverses opioid effect – Tachycardia, headache, angina, muscle tremors
– Example: naloxone (narcan)
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Cox 2 Inhibitors
Blocks prostaglandins that arise from the cyclooxygenase (COX) metabolic
pathway
A non-steroidal drug to treat arthritic pain
Cautions with Cox 2 & NSAIDS
– GI bleed
– Renal failure
– Asthma reaction
Blood and Drugs
“Coagulation” Terms
Anticoagulation
– Hinder future clot formation by inhibiting conversion of prothrombin to thrombin
(heparin or
lovenox) or reducing amount of vitamin K (coumadin)
Antiplatelet
– Prevents production of TXA2 – causes platelet aggregation and vessel constriction
(I.e.
ASA, plavix)
Thrombolytic
– Dissolves thrombi after formation (I.e. TPA, retavase)
– Used in combo with anticoagulants
More COAG Terms
Glycoprotein IIB/IIA Inhibitors
– Inhibits platelet aggregation
– Used as adjunct with ASA and heparin to decrease clot formation, especially during
invasive
procedures (cath)
– Given IV – follow up via PO med (plavix) with similar action
– Example: Reopro, Integrilin, Aggrastatin
GI & Drugs
H-2 Blockers
Blocks release of histamine, esp w/stress
Histamine stimulates gastric acid secretion
Use:
– Stress ulcers
– Allergic reactions
Examples
– Ranitidine (zantac)
– Famotidine (pepcid)
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Proton Pump Inhibitors
Suppress gastric acid secretion by irreversibly binding with proton-pump system
that controls
hydrogen ion secretion
Use on high risk patients (expensive in IV form!!)
– Vented patients >24 hours
– Thrombocytopenic
Example
– Prevacid
– Prolosec
Drugs Influencing
the Respiratory System
Corticosteroids
