Lisinopril: ACE Inhibitor

• Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor medication
• It is primarily used to treat hypertension (high blood pressure), heart failure, and to improve survival after a heart attack

Mechanism of Action

• Lisinopril inhibits the angiotensin-converting enzyme (ACE)
• ACE is responsible for converting angiotensin I to angiotensin II
• Angiotensin II is a potent vasoconstrictor (a substance that narrows blood vessels)
• Angiotensin II also stimulates the release of aldosterone, which promotes sodium and water retention, increasing blood volume
• By inhibiting ACE, lisinopril reduces the production of angiotensin II, leading to vasodilation (widening of blood vessels) and decreased aldosterone levels
• This results in lower blood pressure and reduced fluid retention

Indications

• Hypertension is a first-line treatment, lisinopril is often selected to manage the disease
• Heart Failure management often includes lisinopril, typically in combination with other medications
• Post-Myocardial Infarction (Heart Attack): Lisinopril is administered to improve survival and reduce the risk of complications after a heart attack
• Diabetic Nephropathy in patients with diabetes can be treated with Lisinopril to help protect kidney function

Administration

• Lisinopril is administered orally in tablet form
• It can be taken with or without food
• The frequency of administration is typically once daily
• Dosage is individualized based on the patient’s condition and response to treatment

Dosage

• Hypertension: A typical starting dose is 10 mg once daily, adjusted based on blood pressure response; the usual maintenance dose is 20-40 mg daily
• Heart Failure: A typical starting dose is 2.5-5 mg once daily, gradually increased to a target dose of 20-40 mg once daily as tolerated
• Post-Myocardial Infarction: Treatment usually begins with 5 mg on the first and second day, followed by 10 mg once daily

Contraindications

• History of Angioedema means Lisinopril is not suitable for individuals with a history of angioedema (swelling of the face, lips, tongue, or throat) related to previous ACE inhibitor use
• Pregnancy means ACE inhibitors like lisinopril are not suitable during pregnancy, especially in the second and third trimesters, due to the risk of fetal harm
• Aliskiren Use is contraindicated when used concurrently (another type of blood pressure medication) in patients with diabetes or kidney impairment

Precautions

• If the patients has Renal Impairment, use with caution in patients with kidney problems, as lisinopril can affect kidney function; dosage adjustments may be necessary
• If the patient suffers from Hypotension, lisinopril can cause a drop in blood pressure, especially in patients who are volume-depleted (e.g., due to diuretic use, dehydration)
• Hyperkalemia means ACE inhibitors can increase potassium levels, so caution is advised in patients at risk of hyperkalemia (high potassium)
• Aortic Stenosis should be approached with caution because of this condition (narrowing of the aortic valve)
• Bilateral Renal Artery Stenosis means use is contraindicated

Interactions

• Diuretics: Concurrent use of diuretics can enhance the blood pressure-lowering effect of lisinopril, potentially leading to hypotension
• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): NSAIDs may reduce the antihypertensive effect of lisinopril and increase the risk of kidney problems
• Potassium-Sparing Diuretics and Potassium Supplements: These can increase the risk of hyperkalemia when taken with lisinopril
• Aliskiren: Concurrent use should be avoided, especially in patients with diabetes or kidney impairment
• Lithium: Lisinopril can increase lithium levels, potentially leading to lithium toxicity

Adverse Effects

• Common side effects include:
  • Dizziness
  • Headache
  • Fatigue
  • Dry cough (a characteristic side effect of ACE inhibitors)
  • Hypotension (low blood pressure)
  • Hyperkalemia (high potassium)
• Less common but more serious side effects include:
  • Angioedema (swelling of the face, lips, tongue, or throat); this is a medical emergency
  • Kidney problems
  • Allergic reactions

Monitoring

• Blood Pressure: Regular monitoring of blood pressure is essential to assess the effectiveness of lisinopril and adjust the dosage accordingly
• Kidney Function should be monitored (e.g., serum creatinine, BUN), especially in patients with pre-existing kidney disease
• Potassium Levels should be monitored to detect and manage hyperkalemia
• Signs of Angioedema: Patients should be educated about the signs and symptoms of angioedema and instructed to seek immediate medical attention if they occur

Special Populations

• Pregnancy is a contraindication during pregnancy due to the risk of fetal harm. If a woman becomes pregnant while taking lisinopril, it should be discontinued immediately
• Breastfeeding is not recommended for use, as it is unknown whether lisinopril is excreted in breast milk
• Elderly may be more sensitive to the effects of lisinopril, and lower starting doses may be necessary

Overdosage

• Symptoms of lisinopril overdose may include:
  • Severe hypotension
  • Dizziness
  • Electrolyte imbalances
• Treatment of overdose typically involves supportive care, such as:
  • Intravenous fluids to increase blood pressure
  • Monitoring of vital signs and electrolytes

Clinical Pharmacology

• Absorption: Lisinopril is absorbed from the gastrointestinal tract, with bioavailability (the fraction of the drug that reaches systemic circulation) of about 25%
• Distribution: It does not bind extensively to plasma proteins
• Metabolism: Lisinopril is not metabolized by the liver; it is excreted unchanged in the urine
• Excretion: It is primarily excreted by the kidneys

Patient Education

• Patients should be educated about:
  • The purpose of lisinopril and how to take it
  • Potential side effects, including the risk of angioedema
  • The importance of monitoring blood pressure and kidney function
  • The need to inform healthcare providers about all medications they are taking, including over-the-counter drugs and supplements
  • The importance of regular follow-up appointments with their healthcare provider
  • The need to avoid becoming dehydrated
• They should also be advised to seek medical attention if they experience any unusual symptoms or signs of an allergic reaction

Specific Considerations

• Dry Cough: A persistent dry cough is a common side effect of ACE inhibitors; if it becomes bothersome, alternative medications (e.g., angiotensin receptor blockers or ARBs) may be considered
• Angioedema: Patients should be educated on the signs and symptoms of angioedema (swelling of the face, lips, tongue, or throat) and instructed to seek immediate medical attention if it occurs, as it can be life-threatening
• Drug Interactions: Caution should be exercised when prescribing lisinopril with other medications that can affect blood pressure, kidney function, or potassium levels

Brand Names

• Lisinopril is available under various brand names:
  • Prinivil
  • Zestril
• Lisinopril is also available as a generic medication

Storage

• Lisinopril tablets should be stored at room temperature, away from moisture and light
• Keep medications out of the reach of children

Importance of Adherence

• Emphasize to patients the importance of taking lisinopril regularly as prescribed
• Consistent adherence to the medication regimen is necessary for optimal blood pressure control and to reduce the risk of cardiovascular events