Diuretics Flashcards
Drug: Furosemide (Lasix®) (Loop Diuretic)
Uses: Pulmonary edema and the edema associated with heart failure, liver disease, nephrotic syndrome, ascites, hypertension.
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Most commonly used loop diuretic.
Drug: Mannitol (Osmitrol®) (Osmotic Diuretic)
Most used osmotic diuretic.
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Administration: Intravenous (IV) infusion only.
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Storage: May crystallize when exposed to low temperatures; vials are often stored in a warmer.
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Administration Requirement: Use of a filter is required.
Drug: Spironolactone (Aldactone®) (Potassium-Sparing Diuretic)
Also known as an aldosterone-inhibiting diuretic.
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Indications: Hyperaldosteronism, hypertension, reversing potassium loss caused by potassium-wasting diuretics, certain cases of heart failure: prevention of remodelling.
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Adverse Effects: Gynecomastia, amenorrhea, irregular menses, postmenopausal bleeding.
Drug: Hydrochlorothiazide (Urozide®) (Thiazide Diuretic)
Example of a thiazide diuretic.
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Part of one of the most prescribed group of drugs for hypertension.
Indication: Edema associated with heart failure and liver or kidney disease
Treated with loop diuretics.
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Carbonic anhydrase inhibitors are also used as adjunct therapy for edema secondary to heart failure.
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Thiazide and thiazide-like diuretics are indicated for edematous states
Indication: Hypertension
Diuretic drugs are a mainstay of therapy for the treatment of hypertension.
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Loop diuretics can be used to control hypertension.
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Potassium-sparing diuretics (spironolactone and triamterene) are indicated for hypertension.
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Thiazide and thiazide-like diuretics are one of the most prescribed groups of drugs for hypertension.
Indication: Glaucoma (Open-Angle and Secondary)
Carbonic anhydrase inhibitors are adjunct drugs in the long-term management of open-angle glaucoma and adjunct therapy for secondary glaucoma.
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Carbonic anhydrase inhibitors are used with miotics to lower intraocular pressure before ocular surgery in certain cases.
Contraindication: Hypokalemia
Carbonic anhydrase inhibitors are contraindicated in patients with hypokalemia
What percentage of sodium and water is typically reabsorbed in the proximal convoluted tubule?
60 to 70% of sodium and water is returned to the bloodstream by the proximal convoluted tubule
What percentage of sodium is reabsorbed in the ascending loop of Henle?
20 to 25% of all sodium is reabsorbed into the bloodstream in the ascending loop of Henle.
What percentage of sodium is reabsorbed in the distal convoluted tubule?
5 to 10% is reabsorbed in the distal convoluted tubule.
What is the role of the collecting duct in filtrate processing?
The collecting duct is the final common pathway for the filtrate that started in the glomerulus.
What are carbonic anhydrase inhibitors primarily used for in the long term?
Carbonic anhydrase inhibitors are primarily used as adjunct drugs in the long-term management of open-angle glaucoma and as adjunct therapy for secondary glaucoma.
How are carbonic anhydrase inhibitors used before ocular surgery in certain glaucoma cases?
Carbonic anhydrase inhibitors are used with miotics to lower intraocular pressure before ocular surgery in certain cases.
Besides glaucoma, what other conditions may carbonic anhydrase inhibitors be useful in treating?
Carbonic anhydrase inhibitors may also be useful in the treatment of: edema, secondary to heart failure; high-altitude sickness; and epilepsy.
What are the main contraindications for using carbonic anhydrase inhibitors?
Contraindications for carbonic anhydrase inhibitors include: known drug allergy, hyponatremia, hypokalemia, severe kidney or liver dysfunction, adrenal gland insufficiency, and cirrhosis.
List some common adverse effects associated with carbonic anhydrase inhibitors.
Common adverse effects associated with carbonic anhydrase inhibitors include: acidosis, hypokalemia, drowsiness, anorexia, paresthesias, hematuria, urticaria, photosensitivity, and melena (blood in the stool).
How might carbonic anhydrase inhibitors interact with digoxin? Why?
Because carbonic anhydrase inhibitors can cause hypokalemia, an increase in digoxin toxicity may occur when they are combined with digoxin.
What is a potential interaction between carbonic anhydrase inhibitors and corticosteroids?
Use of carbonic anhydrase inhibitors with corticosteroids may also cause hypokalemia.
What are some drugs whose effects may be increased with concurrent use of carbonic anhydrase inhibitors?
The effects of amphetamines, carbamazepine, cyclosporine, phenytoin, and quinidine sulphate may be increased with concurrent use of carbonic anhydrase inhibitors.
Name three common loop diuretic medications.
Three common loop diuretic medications are bumetanide, ethacrynic acid (rarely used clinically), and furosemide (Lasix®).
What are the main indications for loop diuretics?
Main indications for loop diuretics include: edema associated with heart failure and liver or kidney disease; hypertension (to control); increasing kidney excretion of calcium in patients with hypercalcemia; and heart failure resulting from diastolic dysfunction.
List some central nervous system adverse effects of loop diuretics.
Central nervous system adverse effects of loop diuretics include: dizziness, headache, tinnitus, and blurred vision.
What are some gastrointestinal adverse effects of loop diuretics?
Gastrointestinal adverse effects of loop diuretics include: nausea, vomiting, and diarrhea.
What are some hematological adverse effects of loop diuretics?
Hematological adverse effects of loop diuretics include: agranulocytosis, neutropenia, and thrombocytopenia.
What are some metabolic adverse effects of loop diuretics?
Metabolic adverse effects of loop diuretics include: hypokalemia, hyperglycemia, and hyperuricemia.
What are two potential types of toxicities associated with loop diuretics?
Loop diuretics can be neurotoxic and nephrotoxic
What serum levels might loop diuretics increase?
Loop diuretics might increase serum levels of uric acid, glucose, alanine aminotransferase, and aspartate aminotransferase.
How might the combination of a loop diuretic and metolazone (a thiazide) affect the nephron? What is this called?
Combining a loop diuretic with thiazide (metolazone) can result in sequential nephron blockade, leading to increased diuresis.
How might NSAIDs affect the action of loop diuretics?
Nonsteroidal anti-inflammatory drugs (NSAIDs) may decrease the reduction of vascular resistance caused by loop diuretics.
What is the most commonly used loop diuretic?
Furosemide (Lasix) is the most commonly used loop diuretic.
What are some common uses for furosemide (Lasix)?
Furosemide (Lasix) is used for pulmonary edema and the edema associated with heart failure, liver disease, nephrotic syndrome, ascites, and hypertension.
Name four examples of osmotic diuretics. Which is the most used?
Examples of osmotic diuretics include mannitol (Osmitrol®) (most used), urea, organic acids, and glucose.
What are the main indications for osmotic diuretics?
Main indications for osmotic diuretics include: treatment of patients in the early, oliguric phase of acute kidney injury; to promote excretion of toxic substances; to reduce intracranial pressure; treatment of cerebral edema; and as a genitourinary irrigant.
List some adverse effects associated with osmotic diuretics.
Adverse effects associated with osmotic diuretics include: convulsions, thrombophlebitis, pulmonary congestion, headaches, chest pains, tachycardia, blurred vision, chills, and fever.
How is mannitol (Osmitrol) administered? What are some important considerations for its administration?
Mannitol (Osmitrol) is administered by intravenous (IV) infusion only. It may crystallize when exposed to low temperatures, so vials are often stored in a warmer, and use of a filter is required.
What is another name for potassium-sparing diuretics? Name three examples.
Potassium-sparing diuretics are also known as aldosterone-inhibiting diuretics. Examples include amiloride (Midamor®), spironolactone (Aldactone®), and triamterene.
For what conditions are spironolactone and triamterene typically indicated?
Spironolactone and triamterene are typically indicated for hyperaldosteronism, hypertension, reversing potassium loss caused by potassium-wasting diuretics, and certain cases of heart failure (prevention of remodelling).
How does the long-term effectiveness of amiloride compare to spironolactone and triamterene?
Amiloride is similar to spironolactone and triamterene but less effective in the long term.
What are some common central nervous system and gastrointestinal adverse effects of potassium-sparing diuretics?
Common central nervous system adverse effects include dizziness and headache. Gastrointestinal adverse effects include cramps, nausea, vomiting, and diarrhea.
What is a key electrolyte imbalance to monitor for with potassium-sparing diuretics? What other general adverse effect might occur?
A key electrolyte imbalance to monitor for is hyperkalemia. Other general adverse effects include urinary frequency and weakness.
List some specific adverse effects associated with spironolactone (Aldactone).
Specific adverse effects associated with spironolactone (Aldactone®) include gynecomastia, amenorrhea, irregular menses, and postmenopausal bleeding.
What are some drug interactions to be aware of with potassium-sparing diuretics?
Drug interactions to be aware of include with lithium, angiotensin-converting enzyme inhibitors, potassium supplements, and NSAIDs.
Name a common thiazide diuretic and three thiazide-like diuretics.
A common thiazide diuretic is hydrochlorothiazide (Urozide®). Thiazide-like diuretics include metolazone (Zaroxolyn®), chlorthalidone, and indapamide.
What are the main indications for thiazide and thiazide-like diuretics?
ain indications for thiazide and thiazide-like diuretics include hypertension (one of the most prescribed groups), edematous states, idiopathic hypercalciuria, diabetes insipidus, and heart failure caused by diastolic dysfunction.
What are some central nervous and gastrointestinal adverse effects of thiazide and thiazide-like diuretics?
Central nervous adverse effects include dizziness, headache, and blurred vision. Gastrointestinal adverse effects include anorexia, nausea, vomiting, and diarrhea.
What are some genitourinary, hematological, and integumentary adverse effects of thiazide and thiazide-like diuretics?
Genitourinary: erectile dysfunction. Hematological: jaundice, leukopenia, agranulocytosis. Integumentary: urticaria, photosensitivity.
What are some metabolic adverse effects of thiazide and thiazide-like diuretics?
Metabolic adverse effects include hypokalemia, glycosuria, hyperglycemia, hyperuricemia, and hypochloremic alkalosis.
What are some key aspects of nursing assessment that should be performed before initiating diuretic therapy?
Key aspects include: thorough patient history and physical examination; assessment of baseline fluid volume status, intake and output, serum electrolyte values, weight, and vital signs (especially postural blood pressure); and assessment for contraindications or need for cautious use.
When should patients ideally take their diuretic medication, and why?
Patients should ideally take their medication in the morning if possible to avoid interference with sleep patterns due to increased urination.
What electrolyte level is crucial to monitor during diuretic therapy?
It is crucial to monitor serum potassium levels during therapy.
What dietary education should nurses provide to patients taking most diuretics (excluding potassium-sparing)?
Nurses should teach patients to maintain proper nutritional and fluid volume status and to eat more potassium-rich foods.
What instructions should nurses provide to patients regarding changes in position to minimize adverse effects of diuretics?
Teach patients to change positions slowly and to rise slowly after sitting or lying, to prevent dizziness and fainting related to orthostatic hypotension.
What self-monitoring activity should nurses encourage patients taking diuretics to perform daily?
Encourage patients to keep a log of their daily weight.
List some signs and symptoms of hypokalemia that patients should be aware of.
Signs and symptoms of hypokalemia include anorexia, nausea, lethargy, muscle weakness, mental confusion, and hypotension.
