Pharmacology Unit 1

sodium chloride (NaCl)

electrolyte/sodium supplement; used to treat hyponatremia below 130

adverse effects of NaCl

hypernatremia, pulmonary edema, lethargy/confusion, muscle tremor, hypotension; requires constant lab assessments (BMP, serum sodium, urine specific gravity, serum/urine osmolarity)

Normal saline (0.9% NaCl) uses

mild hyponatremia (<130)

3% and 9% NaCl uses

severe hyponatremia (<115)

additional NaCl uses

ophthalmic drops for corneal edema, nasal spray for dry nasal membranes, abortifacient late pregnancy

NaCl contraindications

heart failure, impaired kidney function, hypernatremia

treatment of NaCl overdose

diuretic

patient education for NaCl

Teach patient to report symptoms of fluid overload (trouble breathing and edema); to drink water or sports drinks to replenish lost fluids/electrolytes

potassium chloride (KCl)

electrolyte/potassium supplement; used to treat hypokalemia

adverse effects of KCl

GI irritation (N/V - when PO), hyperkalemia, phlebitis/venous irritation (When IV)

KCl administration alerts

IV in a larger vessel, give oral medication upright, whole tablet, dilute liquid PO or NGT forms, NEVER IV push or large infusion rate, check for extravasation/infiltration

KCl contraindications

hyperkalemia, CKD, systemic acidosis, severe dehydration, extensive tissue breakdown/severe burns, adrenal insufficiency, digoxin intoxication, or taking potassium-sparing diuretics

KCl interactions

potassium-sparing diuretics and ACE inhibitors

treatment of KCl overdose

all potassium containing/increasing meds/foods should be withheld; IV 10% dextrose and 10-20 units insulin; sodium bicarbonate for acidosis; Polystyrene sulfonate (Kayexalate) to excrete potassium in stool

KCl patient education

teach to report weight gain/loss of 2lb or more in 24 hr period; report electrolyte imbalance s/s of changes in pulse, BP, N/V, GI cramping, diarrhea, muscle weakness, cramping or twitching, parathesis, confusion, decrease LOC, decrease urine output, seizures; monitor for orthostatic hypotension and inform patient of dizziness and how to safely change positions and call for help to get up; tell patient to report cardiac s/s like dyspnea, itching, chest pain/tightness, palpitations, headache; instruct patient to report IV site irritation; instruct patient on avoiding potassium rich foods (strawberries, bananas, tomatoes, beets, beans, fruit juice, prunes, apricots, fresh meat, and salt substitutes); eliminate alcohol; pt should increase fluids to 2L/day and increase fiber; report severe constipation; teach patient about the drug, how to administer, appropriate dosing and scheduling, adverse effects and reporting, and how long to improve

cholinergic agent

stimulate parasympathetic nervous system

Parasympathomimetics

stimulate parasympathetic nervous system

cholinergic-blocking agents

inhibit parasympathetic nervous system

anticholinergics

inhibit parasympathetic nervous system

parasympatholytic

inhibit parasympathetic nervous system

muscarinic blocker

inhibit parasympathetic nervous system

bethanechol (Urecholine)

prototype direct acting cholinergic agent

physostigmine (Antilirium)

prototype indirect acting cholinergic agent; treatment of severe anticholinergic toxicity

cholinergic agent uses

glaucoma, urinary retention (direct acting); myasthenia gravis, Alzheimer’s disease (indirect acting on AchE)

cholinergic agents adverse effects

profuse salivation, sweating, increased muscle tone, urinary frequency, bradycardia, hypotension, abdominal cramping

bethanechol (Urecholine) uses

stimulates smooth muscle contraction in GI tract and urinary bladder; help with post-anesthesia BM return and nonobstructive urinary retention

bethanechol (Urecholine) administration alerts

never IM or IV, oral and subcutaneous doses are not interchangeable, monitor vitals before and after SQ administration

bethanechol (Urecholine) contraindications

GI problems like bowel obstruction, active ulcer, or IBD; urinary obstruction or COPD; asthma, epilepsy, parkinsonism, hyperthyroidism, PUD, bradycardia

treatment of bethanechol (Urecholine) overdose

Atropine sulfate to fix cholinergic crisis (low BP and HR)

monitoring cholinesterase inhibitors (important for myasthenia gravis)

monitor muscle strength, neuromuscular status, ptosis, diplopia, chewing, schedule meds around mealtime, schedule activities to avoid fatigue

patient education of cholinergic drugs

teach to monitor HR and BP and to report if too low; report dizziness and teach how to ambulate safety (increased need to go to bathroom, increased dizziness, increased fall risk); teach to report dyspnea, salivation, sweating, extreme fatigue, muscle weakness; monitor hepatic function lab work and teach pt importance of returning for lab work; caution patient on decrease in vision in dark; teach pt and family about correct dosing and administration; take tablet with thicker food/drink if dysphagia

Cholinergic-blocking drug effects

Pupil dilation (mydriasis), increasing heart rate, drying glandular secretions, relaxing bronchi

Anti-cholinergic drug uses

Peptic Ulcer Disease, ophthalmic procedures, heart rhythm abnormalities, anesthesia adjunct, asthma, COPD, overactive bladder, Parkinson’s disease

atropine (AtroPen, Atropair, Atropisol) use

reverse poisoning with anticholinesterase agents to increase heart rate and dilate pupils; peptic ulcers, IBS, mydriasis and cycloplegia during eye examination, bradycardia, preanesthetic, asthma

cholinergic-blocking agent adverse effects

tachycardia, CNS stimulation (severe: delirium and coma), dry mouth, constipation, urinary retention, dry eyes, decreased sweating, photophobia

atropine contraindications

glaucoma, obstructive disorders of GI tract, paralytic ileus, bladder neck obstruction, benign prostate hyperplasia, myasthenia gravis, cardiac insufficiency, or acute hemorrhage

atropine administration alerts

oral and SQ doses are not interchangeable; monitor BP, pulse, and respirations before and at least an hour after SQ administration

treatment of atropine overdose

physostigmine is an antidote for atropine poisoning; reverses coma

special considerations for atropine use

minimize exposure to heat, cold, strenuous exercise because can’t sweat/regulate temp; monitor I/Os bc can cause urine retention; monitor for abdominal distension and auscultate bowel sounds bc can cause constipation; asses for and report tachycardia, hypertension, dysrhythmias, tremors, dizziness, headache, or decreased urinary output; seizures or ventricular tachycardia may signal drug toxicity

patient education for anticholinergic drugs

instruct to not drink much water (more important if hospitalized - if managing at home, pt should drink more fluids and eat more fiber and report difficulty with urination or constipation); instruct patient to immediately report palpitations, shortness of breath, dizziness, syncope, and dysphagia; teach pt and family to monitor BP and HR and report too high values; provide eye comfort and instruct to wear sunglasses because dilated eyes; teach patient about appropriate dosing and scheduling and reason for drug (especially if inhaler or eye drops)

Alpha 1 adrenergic receptor

all sympathetic target organs except heart; vasoconstriction, pupil dilation, closure of bladder sphincter

Alpha 2 adrenergic receptor

inhibit release of norepinephrine; sympathetic NS brake check; on presynaptic neuron

Beta 1 adrenergic receptor

in heart and kidney; increase HR and force of contraction; release renin to increase BP and BV

Beta 2 adrenergic receptor

in all sympathetic target organs except heart; mostly in lungs; inhibit smooth muscle; bronchodilation

Beta 3 adrenergic receptor

in all adipose tissue and urinary bladder; lipolysis for energy; relaxation of detrusor muscle to hold more urine

adrenergic agents

stimulation of sympathetic response

sympathomimetic

stimulation of sympathetic response

adrenergic-blocking agents

inhibition of sympathetic response

adrenergic antagonist

inhibition of sympathetic response

Sympatholytics

inhibition of sympathetic response

phenylephrine (Neo-Synephrine)

prototype adrenergic agent; in cold and flu medicine; decongestion

adrenergic agent uses

A1 receptors used for nasal congestion, hypotension, dilation of pupils for eye exam; A2 treats hypertension (sympathetic inhibitor endogenously); B1 treats cardias arrest, heart failure, shock; B2 treats asthma and premature labor contractions (inhibit smooth muscle)

Adrenergic agents adverse effects

tachycardia, hypertension, dysrhythmias, CNS overexcitation and seizures, dry mouth, N/V, anorexia

phenylephrine (Neo-Synephrine) intranasal administration uses

reduces nasal congestion by constricting small blood vessels in the mucosa

phenylephrine (Neo-Synephrine) topical administration uses

dilate the pupil when applied topically to the eye

phenylephrine (Neo-Synephrine) parenteral administration uses

reverse acute hypotension without cardiac side effects

phenylephrine (Neo-Synephrine) adverse effects

burning of nasal mucosa or rebound congestion if used too long; narrow-angle glaucoma; high doses can cause reflex bradycardia; anxiety, restlessness, and tremors

phenylephrine (Neo-Synephrine) contraindications

pts with CAD, hypertension, or hyperthyroidism; may cause increase in basal metabolic rate in pt with hyperthyroidism causing increased blood pressure and ventricular tachycardia; acute pancreatitis, heart disease, hepatitis, glaucoma

phenylephrine (Neo-Synephrine) black box warning

severe reactions, including death, may occur with IV infusion

phenylephrine (Neo-Synephrine) administration alerts

parenteral administration can cause tissue injury with extravasation and eye drops may damage soft contact lenses

treatment of phenylephrine (Neo-Synephrine) overdose

OD may cause tachycardia and hypertension; phentolamine (Regitine) may increase blood pressure

things to monitor for phenylephrine (Neo-Synephrine)

vital signs, urinary output, and cardiac function; breathing patterns; observe responsiveness to light; monitor for rhinorrhea and epistaxis; monitor IV site for blanching; monitor blood glucose esp with diabetics

phenylephrine (Neo-Synephrine) patient education

teach pt and family how to monitor BP and HR; teach to report dyspnea and not to take more medication than indicated; instruct to report palpitations, chest pain, anxiety, tremors, headache, urinary retention; teach to limit or eliminate caffeine; instruct pt to not use nasal spray longer than 3-5 days; instruct that photosensitivity may occur; teach diabetic to monitor glucose more carefully; instruct how to properly use inhaler forms; inform pt of drug reason and correct use and have pt restate for understanding

Adrenergic-blocking agents uses

treatment of hypertension, angina pectoris, migraines, heart failure; “beta blockers”

prazosin (Minipress)

prototype drug of adrenergic-blocking agent

prazosin (Minipress) uses

hypertension, dysrhythmias, angina, heart failure, benign prostatic hyperplasia, glaucoma; alpha 1 adrenergic antagonist that interferes at receptor on smooth muscle in arterioles and veins; produces rapid decrease in constriction to reduce blood pressure; causes less reflex tachycardia than other drugs

adrenergic-blocking agent adverse effects

dizziness, drowsiness, loss of energy and strength, palpitations, dry mouth

prazosin (Minipress) administration alerts

give low first dose to avoid severe hypotension and give at bedtime to reduce risk of falls

prazosin (Minipress) adverse effects

orthostatic hypotension, dizziness, drowsiness, reflex tachycardia, bradycardia, nasal congestion, inhibition of ejaculation; especially worried about elderly because dehydration is common

things to monitor for adrenergic blocker

monitor urinary hesitancy, incomplete bladder emptying, interrupted urinary stream especially for when treating BPH; vitals signs, LOC, and mood (may cause depression); dizziness, drowsiness; cardiac output; I/Os and weights; monitor blood glucose

patient education for prazosin (Minipress)

educate pt and family on monitoring weight, HR, BP, and dizziness; teach how to change positions and stand slowly; instruct pt to report dizziness, dyspnea, chest pain, palpitations; tell pt to report changes in mood and depression; tell patient that vision may get blurry and decrease at night; teach pt and family to never abruptly stop medication because rebound hypertension and tachycardia may occur; teach why and how about drug