Cholesterol Management and Lipid Profiles

Overview of Antilipemic Agents

• Antilipemic agents are used in managing cholesterol levels. They work by:

  • Reducing Low-Density Lipoprotein (LDL) cholesterol

  • Increasing High-Density Lipoprotein (HDL) cholesterol

  • Decreasing Very Low-Density Lipoprotein (VLDL) cholesterol

Lifestyle Modifications

• Recommended lifestyle changes to complement medication include:

  • Regular exercise

  • A balanced diet

  • Weight control

Baseline Lab Tests for Cholesterol Management

• Important lab tests include:

  • Total cholesterol measurement

  • LDL cholesterol measurement

  • HDL cholesterol measurement

  • Triglycerides measurement

  • Liver function test

  • Kidney function test

Lipid Profile Components and Categories

• Lipid Profile Values:

  • HDL (High-Density Lipoprotein) Cholesterol:

  • Normal for Men: ≥ 40 mg/dL (≥ 1.0 mmol/L)

  • Normal for Women: ≥ 50 mg/dL (≥ 1.3 mmol/L)

  • Optimal: ≥ 60 mg/dL (≥ 1.5 mmol/L) - this level is protective against heart disease

  • LDL (Low-Density Lipoprotein) Cholesterol:

  • Optimal: < 100 mg/dL (< 2.6 mmol/L)

  • Total Cholesterol:

  • Desirable: < 200 mg/dL (< 5.2 mmol/L)

  • Triglycerides:

  • Normal: < 150 mg/dL (< 1.7 mmol/L)

  • Very High: ≥ 500 mg/dL (≥ 5.6 mmol/L)

Management and Improvement of Cholesterol Levels

• Aim to promote heart health through various medications, notably:

  • HMG-CoA Reductase Inhibitors (Statins):

  • Atorvastatin

  • Simvastatin

  • Lovastatin

  • Pravastatin

  • Rosuvastatin

  • Fluvastatin

  • Pitavastatin

  • Combination Medications:

  • Simvastatin and Ezetimibe

Mechanisms of Action for Statins

• Statins work by:

  • Blocking cholesterol production via the HMG-CoA pathway.

  • Cleaning up the blood by reducing the production of bad fats.

  • Reducing inflammation which may contribute to heart disease.

Therapeutic Uses of Statins

• Indicated for:

  • Hypercholesterolemia (high cholesterol levels)

  • Prevention of coronary events in diabetic patients

Complications Associated with Statin Use

• Potential complications include:

  • Hepatotoxicity:

  • Enzyme elevation

  • Liver cell stress leading to inflammation and cell death

  • Myopathy:

  • Reduction of CoQ10

  • Disruption of muscle cell membranes can be exacerbated by genetic predisposition

Warnings and Contraindications

• Pregnancy Warning: Use is contraindicated during pregnancy.

• Lactation Warning: Caution in breastfeeding.

• Reproductive Warning: Patients with reproductive concerns should consult healthcare providers.

• Contraindications:

  • Clients with liver disorders should avoid statin use.

Other Cholesterol-Lowering Agents

• Fibrates:

  • Examples include Gemfibrozil and Fenofibrate.

  • Known to interact with other medications such as Erythromycin and Ketoconazole, which suppress CYP34A4.

  • Caution with grapefruit juice as it may interfere with the metabolism of these agents.

Safety Considerations

• Be aware of the risk of Rhabdomyolysis, which can result from interactions with certain medications.

• Regular monitoring and assessment may be necessary for patients undergoing treatment with these drugs.

Nursing Administration of Statins

• Statins are a class of medications used to lower cholesterol levels.

• Administering Stains:

  • Statins are administered via the oral route.

  • Lovastatin: Should be taken with the evening meal for optimal effectiveness.

  • Other statins can be taken at any time of day, but evening dosing is preferred since most cholesterol synthesis occurs overnight.

Complications Associated with Statins

• Potential complications from statin therapy include:

  • Constipation: A common side effect noted in patients taking statins.

Bile-Acid Sequestrants

• Colesevelam: A bile-acid sequestrant used to manage cholesterol levels.

• Other medications in this category include:

  • Colestipol

• Pharmacological Actions:

  • Mechanism of action includes binding of bile acids and the prevention of bile acid reabsorption, which encourages increased cholesterol utilization.

Contraindications for Bile-Acid Sequestrants

• Colesevelam is contraindicated in the following situations:

  • During pregnancy and breastfeeding (reproductive warning).

  • Patients with bowel obstructions.

  • Patients with pancreatitis.

• Use cautiously in patients with dysphagia and gastrointestinal (GI) disorders.

Therapeutic Uses of Bile-Acid Sequestrants

• Colesevelam may be used alone or as an adjunct medication alongside atorvastatin for enhanced lipid-lowering effects.

Drug Interactions with Bile-Acid Sequestrants

• Significant interactions with the following medications were noted:

  • Levothyroxine

  • Oral Glipizide

  • Phenytoin

  • Fat Soluble Vitamins: (ADEK)

  • Digoxin

  • Warfarin

  • Contraceptives

  • Diuretics

Client Education Related to Bile-Acid Sequestrants

• Colesevelam Administration:

  • Taken orally in tablet form.

  • Must be taken with food and 8 oz of water.

  • Should not be taken with other medications to avoid interactions.

• Colestipol Administration:

  • Available as an oral tablet that should not be crushed or chewed.

  • Administer 30 minutes before a meal.

  • Also available in a powder form that can be mixed with liquids.

• Dietary Recommendations:

  • Increase dietary fiber intake and fluid consumption.

  • Consider taking a mild laxative if constipation occurs.

  • Use adequate fluid (4 to 8 oz) when dissolving Colestipol powder to prevent esophageal irritation or impaction.

Indications for Diuretics in Nursing

• Indications for diuretics include:

  • Blood Pressure Control: Effective management of hypertension.

  • Fluid Removal: Used to expel excess fluids from the body.

• Types of Diuretics:

  • Loop Diuretics: Affecting the heart, liver, and kidneys.

  • Thiazide Diuretics: Also targeting the cardiovascular and renal systems.

  • Potassium-Sparing Diuretics: Used in specific patient populations to avoid hypokalemia.

  • Osmotic Diuretics: Typically utilized in critical care settings.

LOOP DIURETICS - Furosemide

OTHER MEDICATIONS

• Ethacrynic acid

• Bumetanide

• Torsemide

ACTION

• Site of Action: Loop of Henle

  • Proximal Tubule:

  • Inhibition of NKCC2

  • Distal Tubule:

  • Increased excretion of Na and H2O

  • Effect on Electrolytes

  • Vasodilation

  • Bowman's Capsule

  • Connecting Duct

THERAPEUTIC USES

• Rapid fluid mobilization

• Pulmonary edema from heart failure

• Conditions unresponsive to other diuretics

ROUTE OF ADMINISTRATION

• Oral (PO)

• Intramuscular (IM)

• Intravenous (IV)

COMPLICATIONS

• HYPOKALEMIA

• DEHYDRATION

• OTOTOXICITY

• HYPONATREMIA

• HYPOCHLOREMIA

• HYPOTENSION

• OTHER ADVERSE EFFECTS

CONTRAINDICATIONS/PRECAUTIONS

1. Anuria

2. Certain Medical Conditions

3. Certain Medications

INTERACTIONS

1. Antihypertensives

2. Digoxin (toxicity)

3. NSAIDs

NURSING ADMINISTRATION

• Obtain baseline data:

  • Orthostatic blood pressure

  • Weight

  • Electrolytes

  • Extent of edema

• Weigh clients daily at the same time, same clothing/bed linen amount.

• Monitor blood pressure and Input & Output (I&O).

• Administer medication early in the day to avoid nocturia, usually at 0800 and 1400.

• Administer furosemide via:

  • Oral, IM, IV bolus dose, or continuous IV infusion;

  • Infuse IV doses at a rate of 20 mg/min or slower.

• If potassium < 3.5 mEq/L, monitor ECG; possibly need potassium supplement.

• Client Education:

  • Self-monitor blood pressure and weight

  • Get up slowly

  • Report significant weight loss, lightheadedness, dizziness, gastrointestinal distress, general weakness.

  • Consume potassium-rich foods

  • Monitor blood glucose if diabetic

• Observe for low magnesium/calcium symptoms:

  • Muscle twitching

  • Tremors

  • Cramps

  • Tingling

• Report ototoxicity signs:

  • Tinnitus

  • Hearing loss

Sonic Calcium Effectiveness Evidenced by: Weight Loss and Related Factors

• Weight Loss

  • Effectiveness of calcium in promoting weight loss.

• Edema

  • Definition: Swelling caused by excess fluid trapped in body tissues.

• Urine Output

  • Importance in managing fluid balance.

• Blood Pressure

  • Monitoring and effects on overall health.

Potential Complications Associated with Treatment

• Hypokalemia

  • Definition: Low potassium levels in the blood.

  • Risks: Muscle weakness, cramps.

• Dehydration

  • Definition: Excess loss of body fluids.

  • Symptoms: Thirst, decreased urine output.

• Hyperglycemia

  • Definition: High blood sugar levels.

  • Importance to monitor in diabetic patients.

• Hyponatremia

  • Definition: Low sodium levels in the body.

  • Risks: Confusion, seizures.

• Hypochloremia

  • Definition: Low chloride levels.

  • Associated symptoms: Muscle spasms.

• Hypotension

  • Definition: Low blood pressure.

  • Risks of dizziness and fainting.

Contraindications and Precautions

• Pregnancy and Lactation

  • Special considerations for use during pregnancy and while breastfeeding.

• Certain Renal Impairment

  • Caution required for patients with kidney dysfunction.

• Medications and Conditions

  • Other medications or medical conditions that may conflict with treatment.

Drug Interactions

• Loop Diuretic Interaction

  • Notes: Similar interaction potential as loop diuretics.

  • Difference: No risk of hearing loss associated with this medication.

Nursing Administration Guidelines

• Route of Administration

  • Chlorothiazide: Administered either orally or via intravenous (IV).

  • Other medications should be given orally.

• Baseline Data Collection

  • Obtain initial measurements:

  • Orthostatic blood pressure.

  • Weight.

  • Electrolyte levels.

  • Extent of edema.

• Monitoring Protocol

  • Regularly monitor potassium levels.

  • Alternate-day dosing to prevent electrolyte imbalances.

  • Daily weight measurement at the same time each day and monitoring blood pressure and intake/output.

  • If potassium is less than 3.5 mEq/L, monitoring of ECG is essential; potassium supplementation may be needed.

• Preventive Measures for Patients

  • Advise patients to rise slowly to prevent postural hypotension.

  • Assess for symptoms of hypovolemia.

  • Educate patients on actions to take if experiencing faintness or dizziness.

• Client Education

  • Schedule: Take medication in the morning; may take a second dose by 1400 if required.

  • Dietary Advice: Encourage consumption of potassium-rich foods and adequate fluid intake.

  • Administration with meals advised for gastrointestinal (GI) upset.

  • Patients should log blood pressure and weight if they have hypertension.

• Reporting Symptoms

  • Instruct patients to report:

  • Significant weight loss.

  • Lightheadedness.

  • Dizziness.

  • GI distress.

  • General weakness.

• Monitoring for Diabetic Patients

  • Diabetic patients should be monitored for blood glucose levels.

  • Be vigilant for symptoms of low magnesium:

  • Weakness.

  • Muscle twitching.

  • Tremors.

Effectiveness Evidenced By

• Measurement Indicators

  • EDEMA: Swelling caused by fluid retention.

  • BONE INTEGRITY: The condition of bones, indicating health and strength.

  • URINE OUTPUT: The volume of urine produced, important for monitoring kidney function.

  • CO: Cardiac output, a critical measurement of heart function.

  • ↓ BLOOD PRESSURE: A decrease in blood pressure is often desired in hypertensive patients.

Potassium-Sparing Diuretics - Spironolactone

• Action: These medications help the body eliminate water while conserving potassium.

• Other Medications:

  • Triamterene

  • Amiloride

• Site of Action: Distal parts of nephron including the Distal Convoluted Tubule (DCT) and Collecting Duct.

• Mechanism:

  • Aldosterone Antagonists: Spironolactone, which blocks the action of aldosterone.

  • Sodium Channel Blockers: Triamterene and Amiloride which prevent sodium reabsorption.

• Effects:

  • Mild diuretic effect, meaning they induce the production of urine without causing significant potassium loss.

  • Potassium conservation, which is beneficial for preventing hypokalemia (low potassium levels).

Therapeutic Uses

• Indications:

  • Hypertension (HTN): Treatment for high blood pressure.

  • Edema: Swelling due to excess fluid.

  • Heart Failure: A condition where the heart does not pump blood effectively.

  • Hyperaldosteronism: A condition with excessive production of aldosterone.

Therapeutic Effects

• Onset: Therapeutic effects can take 12 to 48 hours to manifest.

Nephron Anatomy

• An overview of kidney structure related to diuretic action:

  • Bowman's Glomerulus: Initiates the filtration of blood.

  • Proximal Tubule: Absorbs nutrients, electrolytes, and water.

  • Loop of Henle: Concentrates urine and reabsorbs water and salts.

  • Distal Convoluted Tubule (DCT): Main site of action for potassium-sparing diuretics.

  • Collecting Duct: Final site for urine concentration.

  • Cortex and Medulla: Regions of the kidney housing different segments of nephron.

Complications

• Potential Side Effects:

  • Hyperkalemia: Elevated potassium levels that can lead to serious heart issues.

  • Endocrine Effects:

  • Gynecomastia (breast tissue development in men)

  • Menstrual irregularities in women

  • Decreased libido: Reduced sexual interest.

  • Erectile dysfunction: Trouble achieving or maintaining an erection.

  • Other Endocrine Effects: Various hormone-related side effects.

  • Metabolic Acidosis: A condition that occurs when the body produces excessive quantities of acid or when the kidneys are not removing enough acid from the body.

Contraindications/Precautions

• Considerations Before Prescription:

  1. Pregnancy: Potential risks to mother and fetus.

  2. Certain Medications: Interactions with other drugs.

  3. Hyperkalemia: Pre-existing high potassium levels can be exacerbated.

Interactions

• Drug Interactions:

  • Potassium Supplements: Increased risk of hyperkalemia when combined.

  • Salt Substitutes: Often potassium-based, can exacerbate potassium retention.

  • ACE Inhibitors: Medications that can also increase potassium levels.

  • Angiotensin Receptor Blockers: Similar action to ACE inhibitors with risk of hyperkalemia.

  • Renin Inhibitors: Drug class that may interact similarly.

Nursing Administration

• Baseline Data Collection

  • Obtain baseline data for effective monitoring and management of client health.

  • Important parameters to measure include:

  • Daily Weighing:

    • Should be conducted at the same time each day.

    • Ensure the same amount of clothing and bed linen for consistency.

  • Blood Pressure Monitoring:

    • Regular monitoring of blood pressure values.

    • Intake and Output (I&O) records should be maintained.

  • Periodic ECG Monitoring:

    • Regular ECG assessments to track heart health.

  • Potassium Levels Monitoring:

    • Crucial for clients on certain medications.

• Client Education:

  • Important teaching points include:

  • Avoid potassium-rich foods and potassium-containing salt substitutes.

  • Encourage self-monitoring of blood pressure and weight log maintenance.

  • Inform clients that Triamterene may cause a bluish tint to urine.

  • Report symptoms such as:

    • Cramps

    • Diarrhea

    • Increased thirst

    • Altered menstruation patterns

    • Deepened voice

  • Advise patients to avoid activities requiring alertness until the effects of the medication are known.

Effectiveness Evidence by Edema

• Potassium Levels:

  • The normal range is approximately K^+ = 3.5 - 5.0 ext{ mEq/L}.

Vitamins and Minerals

• Role of Vitamins and Minerals:

  • Support crucial bodily functions, including:

  • Red blood cell production

  • Bone formation

  • Hormone creation

  • Consequences of Nutrient Deficiencies:

  • Can lead to health issues such as:

    • Anemias

    • Heart disease

    • Osteoporosis

  • Importance of Supplements:

  • Various supplements can aid in preventing these health conditions.

  • A balanced diet or supplementation is crucial for ensuring adequate nutrient intake.

  • Maintains overall well-being and assists in disease prevention.

Iron Preparations and Therapeutic Uses

• Oral Iron Preparations:

  • Ferrous sulfate is the primary choice.

• Parenteral Iron Preparations:

  • Iron dextran is commonly used for malabsorption cases.

• Other Medications:

  • Oral: Ferrous gluconate, ferrous fumarate

  • Parenteral: Ferumoxytol, iron sucrose, sodium-ferric gluconate complex (SFGC).

• Purpose of Iron Supplements:

  • Primarily utilized for:

  • Red blood cell (RBC) development

  • Facilitating oxygen (O2) transport to cells.

• Therapeutic Uses:

  • Indicated for conditions like iron deficiency anemia, particularly in patients on long-term dialysis.

Complications

• Potential complications associated with iron supplements may include:

  • Gastrointestinal (GI) distress

  • Teeth staining from oral preparations

  • Anaphylaxis in parenteral administration

  • Hypotension

  • Risk of fatal iron toxicity in overdose scenarios.

Contraindications and Precautions

• Foods to Avoid:

  1. Caffeine and Dairy Products:

  • Can interfere with iron absorption.

  1. Hypersensitivity:

  • Clients with known allergies to iron preparations should avoid them.

  1. Vitamin C:

  • While it enhances iron absorption, it should be administered with caution due to potential side effects when combined with certain conditions or medications.

Potassium SupplementsPotassium Supplement Types

• Potassium chloride (primary supplement)

• Other medications containing potassium:

  • Potassium gluconate

  • Potassium phosphate

  • Potassium bicarbonate

Purpose of Potassium Supplements

• Essential for:

  • Nerve impulses: Facilitates communication between nerve cells.

  • Electrical excitability: Influences the behavior of muscle cells and neurons.

  • Regulation of acid/base balance: Maintains the pH balance in the body fluids.

Therapeutic Uses of Potassium Supplements

• Hypokalemia: Treatment for low potassium levels in the blood.

• Used commonly by individuals receiving:

  • Diuretics: Increases potassium loss in urine.

Complications from Potassium Supplements

• Potential for Hyperkalemia: Excess potassium levels that can lead to serious health issues.

• Risk factors include:

  • Kidney disease: Compromised kidney function can impair potassium excretion.

  • Hypoaldosteronism: Deficiency of aldosterone leading to retention of potassium.

Contraindications

• Caution or avoid use in patients:

  • Taking Potassium-sparing diuretics.

  • On ACE inhibitors: These can increase potassium levels in the blood.

Nursing Administration of Potassium Supplements

• Preparation: Mix powdered potassium in 90-240 mL of cold water or juice.

  • Instruction: Drink slowly over 5-10 minutes to reduce gastrointestinal distress.

• Effervescent potassium tablets: Should be dissolved in 90-240 mL of cold water before consumption.

• Instructions for potassium chloride:

  • Should be taken with meals and plenty of water to minimize stomach upset.

  • Important: Do not crush or chew extended-release tablets. Any issues with swallowing should be reported to a healthcare provider.

• IV Potassium: Administer cautiously with a pump, ensuring not to exceed 10 mEq/hr and closely monitor cardiac status.

Magnesium SupplementsTypes of Magnesium Supplements

• Parenteral form: Magnesium sulfate

• Oral forms:

  • Magnesium hydroxide

  • Magnesium oxide

  • Magnesium citrate

Purpose of Magnesium Supplements

• Essential for:

  • Muscle contractility: Supports normal function of muscles.

  • Blood coagulation: Plays a role in the blood clotting process.

Therapeutic Uses of Magnesium Supplements

• Hypomagnesemia: Treatment for low magnesium levels in the blood.

• Laxatives: Certain oral forms can be used as a laxative.

• Preterm labor: Magnesium sulfate is sometimes used to inhibit contractions in pregnant women.

Complications from Magnesium Supplements

• Potential complications include:

  • Muscle weakness: Excessive magnesium can reduce muscle strength.

  • Flaccid paralysis: Severely high levels can lead to muscle paralysis.

  • Diarrhea: Common side effect of oral magnesium supplements.

Contraindications for Magnesium Supplements

• Pregnancy: Caution used in pregnant women.

• Risk of AV block: Certain heart conduction abnormalities.

• Rectal bleeding: Avoid use in patients with active rectal bleeding.

• Nausea/Vomiting and Abdominal Pain: Avoid in those presenting with these gastrointestinal symptoms.

NURSING ADMINISTRATION

• Monitoring Parameters:

  • Blood magnesium, calcium, and phosphorus levels must be monitored.

  • Blood pressure, heart rate, and respiratory rate should be assessed when administering medications intravenously.

  • Assess for depressed or absent deep tendon reflexes, which may indicate toxicity.

• Toxicity Management:

  • In the case of magnesium sulfate toxicity, administer calcium gluconate.

  • Always have an injectable form of calcium gluconate readily available when magnesium sulfate is administered intravenously.

• Patient Education:

  • Teach clients about dietary sources of magnesium, which include:

  • Whole-grain cereals

  • Nuts

  • Legumes

  • Green leafy vegetables

  • Bananas

INTERACTIONS

• Certain substances can decrease the absorption of specific medications:

  • Tetracyclines

  • Digoxin

CONTRAINDICATIONS

• The following conditions are contraindicated for certain treatments:

  1. Pregnancy

  2. Risk of AV block

  3. Rectal bleeding

  4. Nausea/vomiting and abdominal pain

• Note: Ensure to refer to specific guidelines for management in these contraindicated conditions.

Mechanism of Action - Renin-Angiotensin System

• Blood pressure drop triggers kidney renin release

• Renin converts angiotensinogen → angiotensin I → angiotensin II (potent vasoconstrictor)

• Angiotensin II effects: vasoconstriction, aldosterone release (sodium/water retention), ADH stimulation

ACE Inhibitor Action

• Blocks angiotensin I → angiotensin II conversion

• Results: vasodilation, reduced aldosterone, increased sodium/water excretion, decreased blood pressure

• Reduces cardiac workload

Side Effects Profile

• Orthostatic hypotension - monitor BP for 2 hours after first dose

• Persistent dry cough - due to bradykinin accumulation in lungs

• Hyperkalemia - decreased potassium excretion by kidneys

• Neutropenia (rare but serious) - monitor CBC with differential, educate on infection signs

• Angioedema - life-threatening swelling, treat with epinephrine

• Altered taste - metallic/salty taste due to substance P affecting taste receptors

Contraindications & Precautions

• Pregnancy (Category D), existing angioedema, neutropenia

• Precautions: kidney impairment, vascular diseases (scleroderma, SLE) - increased neutropenia risk

Drug Interactions

• Lithium - increases lithium levels (normal: 0.8-1.2 mEq/L)

• NSAIDs - reduce ACE inhibitor effectiveness, space 2+ hours apart

Angiotensin II Receptor Blockers (ARBs)

• Block AT1 receptors, preventing angiotensin II binding

• Similar effects to ACE inhibitors but different mechanism

• Specific drugs: irbesartan/losartan (diabetic nephropathy), telmisartan (MI/stroke protection), valsartan (heart failure)

Calcium Channel Blockers

• Block calcium channels in heart and blood vessels

• Effects: negative inotrophy (reduced contractility), negative chronotrophy (slower heart rate), reduced oxygen demand

• Two types: Nifedipine (blood vessels), Verapamil/Diltiazem (heart + vessels)

• Side effects: orthostatic hypotension, reflex tachycardia, peripheral edema, constipation (verapamil)

Centrally Acting Alpha-2 Agonists

• Stimulate alpha-2 receptors in brainstem, reduce sympathetic outflow

• Decreases norepinephrine release, reduces heart rate and blood pressure

• Clonidine - also used for ADHD, available as transdermal patch (change weekly)

Beta Blockers

• Block beta-1 (heart) and beta-2 (lungs/vessels) receptors

• Effects: negative inotrophy, chronotrophy, dromotrophy (slows electrical conduction)

• Critical warning: Never discontinue abruptly - risk of rebound myocardial excitation, MI, death

• Propranolol concerns: bronchial constriction (avoid in asthma/COPD), masks hypoglycemia symptoms in diabetics

General Nursing Considerations

• Always monitor blood pressure before giving antihypertensive drugs

• IV medications must be given slowly (2-3 minutes) to prevent rapid BP drop

• Monitor for orthostatic changes, educate patients on position changes

Cardiac Glycoside (Digoxin) - Pharmacology Lecture NotesMechanism of Action

• Positive inotropic effect: Strengthens heart contractions for heart failure treatment

• Inhibits ATP enzyme (sodium-potassium pump): Increases intracellular sodium, leading to stronger muscle contractions

• Parasympathetic effect on AV node: Slows electrical conduction (negative chronotropic effect) - treats atrial fibrillation

Therapeutic Range & Monitoring

• Very narrow therapeutic window between therapeutic and toxic doses

• Therapeutic level: 0.8-2.0 nanograms per mL

• Requires careful monitoring and dosing

Digoxin Toxicity Symptoms

Gastrointestinal (First Signs):

• Loss of appetite (often first sign)

• Nausea, vomiting, abdominal pain

Cardiac (Most Serious):

• Arrhythmias (life-threatening): bradycardia, heart block, atrial tachycardia with block, ventricular arrhythmias

• Palpitations

Central Nervous System:

• Confusion, fatigue, headaches

• Classic visual disturbances: Blurred vision, xanthopsia (yellow/green vision), halos around lights

Electrolyte Imbalance:

• Hyperkalemia

Toxicity Management

• Levels >2.0: Stop medication completely

• Lower toxic levels (e.g., 0.9): Reduce dose only

• Antidote: Digibind (IV infusion over 30+ minutes)

• Critical patients may need rapid administration with ICU monitoring and EKG

• Digibind side effect: Can cause hypokalemia (rapid potassium decrease)

Drug Interactions

• Thiazide/loop diuretics + digoxin: Causes hypokalemia

• ACE inhibitors/ARBs + digoxin: Causes hyperkalemia

• Sympathomimetics (dopamine) + digoxin: Increases risk of abnormal fast heart rhythm

• Verapamil: Increases digoxin levels

• Antacids: Reduce digoxin absorption (decreased effectiveness)

Nursing Considerations

• Monitor heart rate before administration (hold for specific rates in adults, children, infants)

• Administer same time daily to maintain therapeutic levels

• Continuously evaluate for toxicity manifestations

• Pregnancy Category C - benefits may warrant use

Organic Nitrates - Pharmacology LecturePrimary Uses

• Primary indication: Treat and prevent angina pectoris (chest pain)

• Secondary uses: Heart failure, high blood pressure during surgical procedures

• Prophylactic use before activities that trigger angina

Mechanism of Action

• Converts to nitric oxide (natural vasodilator)

• Relaxes smooth muscles in blood vessel walls

• Primary effect on veins, lesser effect on arteries

Hemodynamic Effects

• Decreases preload: Reduces blood returning to heart, decreases workload

• Decreases afterload: Dilates arteries, reduces resistance

• Net result: Decreased heart oxygen demand

Angina Pathophysiology

• Chest discomfort beneath breastbone, radiating to left shoulder, arm, and jaw

• Caused by reduced oxygen supply to heart muscle

Medication Forms

• Nitroglycerin available in multiple forms: oral, sublingual, IV

• Other options: Isosorbide nitrate/mononitrate

Side Effects

• Most common: Headaches (due to increased brain blood flow)

• Orthostatic hypotension, reflex tachycardia

• Headache management: OTC pain meds (aspirin/acetaminophen)

• Contact provider if headaches persist despite treatment

Tolerance

• Body develops tolerance over time, making drug less effective

• Prevention strategies: Lowest effective dose, intermittent dosing (8-hour drug-free periods)

Contraindications

• Liver or kidney dysfunction

• Glaucoma (increases intraocular pressure)

• Traumatic brain injury (increases intracranial pressure)

• Severe anemia (further reduces oxygen delivery)

Critical Drug Interactions

• CONTRAINDICATED with phosphodiesterase inhibitors (Viagra/sildenafil)

• Combination causes severe, life-threatening hypotension

Sublingual Administration Protocol

• At onset of angina: Stop all activities, sit or lie down

• Take 1 sublingual tablet under tongue - do not swallow or chew

• Rest and wait 5 minutes for chest pain to subside

• If no relief after first dose: Call 911, then take second tablet

• Wait another 5 minutes; if no relief, take third tablet

• CRITICAL: Never exceed 3 tablets