Amlodipine
(am-loe-di-peen)Classification
Pharmacotherapeutic: Calcium channel blocker
Clinical: Antihypertensive, antianginal
Apo-AmLODIPine
Norvasc
CATEGORY AND SCHEDULE
Pregnancy Risk Category: C
Do not confuse:
amLODIPine with aMILoride, or Norvasc with Navane or Vascor
General Information
Amlodipine belongs to a group of medicines known as calcium channel blockers, which interfere with the conduction of signals in the muscles of the heart and blood vessels. Amlodipine is used in the treatment of angina to help prevent chest pain attacks. Unlike other angina medications (such as beta blockers), it can be used safely by people with asthma and people with diabetes who require insulin. Amlodipine is also used to lower high blood pressure (hypertension). Like other drugs in its class, amlodipine can lower blood pressure too much at the start of treatment. In rare cases, angina may worsen at the start of treatment with amlodipine
Amlodipine can cause severe reactions such as: overdose can cause excessive peripheral vasodilation, marked hypotension with reflex tachycardia, syncope
Action
It inhibits the entry of calcium ion through the cell membrane during cardiac depolarization; produces relaxation of coronary vascular smooth muscle and peripheral vascular smooth muscle; dilates the coronary vascular arteries; increases myocardial oxygen supply in patients with vasospastic angina
Therapeutic Effect
It dilates the coronary arteries, peripheral arteries / arterioles. Decreases total peripheral vascular resistance and BP due to vasodilation
Availability (Rx)
Tablets: 2.5 mg, 5 mg, 10 mg
Uses
Chronic stable angina pectoris, hypertension, variant angina (Prinzmetal’s angina); may coadminister with other antihypertensives, antianginals
Unlabeled uses: Hypertension (pediatric patients)
Precautions
Pregnancy C, breastfeeding, children, geriatric, CHF, hypotension, hepatic injury, GERD
Black Box Warning: Hypersensitivity to dihydropyridine
• You have long-term liver problems.
• You have heart failure or aortic stenosis.
• You have diabetes.
• You are taking other medicines
Indications and Dosages
‣ To Treat Hypertension
PO
• Adults: Initially, 5 mg/day as a single dose. Maximum: 10 mg/day
• Elderly and Debilitated Patients: Initially, 2.5 mg/day as a single dose. Titrate to 5 mg/day if needed
• Children 6-17 yr: 2.5-5 mg/day as a single dose
‣ To Treat Coronary artery disease
PO
• Adult: 5-10 mg/day
• Geriatric: 5 mg/day, max 10 mg/day
• Eldery, patients with hepatic insufficiency: 5 mg/day as a single dose
‣ To treat angina (chronic stable or vasospastic) and Prinzmetal’s (variant) angina
PO
• Adults: 5-10 mg/day as a single dose
• Elderly: 5 mg/day as a single dose. Maximum: 10 mg
‣ Dosage in hepatic impairment
PO
• For adults and elderly patients, give 2.5 mg/day for hypertension; 5 mg/day for angina
‣ Dosage in Renal Impairment
• No dose adjustment
Pharmacokinetics
Slowly absorbed from the GI tract. Protein binding: 93%. Extensively metabolized in the liver; active drug and metabolites excreted primarily in urine. Not removed by hemodialysis. Half-life: 30-50 h (increased in elderly patients and in those with liver cirrhosis)
Implementation
PO route
• Give once a day, without regard to meals
Contraindications
Severe hypotension, known sensitivity to amlodipine
Cautions: Hepatic impairment, severe aortic stenosis, hypertrophic cardiomyopathy with outflow tract obstruction
Interactions
Individual drugs
• Alcohol, fentaNYL, quiNIDine: increased hypotension
• Diltiazem: increased amLODIPine level
• Lithium: increased neurotoxicity
Drug classifications
• Antihypertensives, nitrates: increased hypotension• NSAIDs: decreased antihypertensive effect
Drug/laboratory tests
• May increase hepatic enzyme levels
Drugs/food
• Grapefruit products may increase concentration, hypotensive effects
Herbal
• St. John’s wort may decrease concentration• Ephedra, yohimbe may worsen hypertension
• Garlic may increase antihypertensive effect
Side effects
• CNS: Anxiety, dizziness, fatigue, headache, lethargy, light-headedness, paresthesia, somnolence, syncope, tremor
• CV: Arrhythmias, hypotension, palpitations, peripheral edema
• EENT: Dry mouth, pharyngitis
• ENDO: Hot flashes
• GI: Abdominal cramps, abdominal pain, constipation, diarrhea, esophagitis, indigestion, nausea
• GU: Decreased libido, impotence, urinary frequency
• MS: Myalgia
• RESP: Dyspnea
• SKIN: Dermatitis, flushing, rash
• Other: Weight loss
Nursing considerations
Baseline assessment
• Assess baseline renal/hepatic function tests, B/P, apical pulseIntervention/evaluation
• Assess B/P (if systolic B/P is less than 90 mm Hg, withhold medication, contact
physician)
• Assess for peripheral edema behind medial malleolus (sacral area in
bedridden pts)
• Assess skin for flushing. Question for headache, asthenia
Equipment must be available for anaphylaxis
• Assess fluid volume status: distended red veins, crackles in lung; color, quality, and specific gravity of urine, skin turgor, adequacy of pulses, moist mucous membranes, bilateral lung sounds, peripheral pitting edema; dehydration symptoms of decreasing output, thirst, hypotension, dry mouth and mucous membranes should be reported
• Assess for angina: intensity, location, duration of pain
• Monitor B/P and pulse; if B/P drops, call prescriber
• Monitor ALT, AST, bilirubin daily; if these are elevated, hepatotoxicity is suspected
• Monitor platelet count: if ,150,000/mm3, product is usually discontinued and another product started
• Monitor cardiac status: B/P, pulse, respiration, ECG
Evaluation
Positive therapeutic result• Decreased anginal pain
• Decreased B/P
• Increased exercise tolerance
Patient/family teaching
• Tell patient to Do not abruptly discontinue medication
• Tell patient to Compliance with therapy regimen is essential to control hypertension
• Tell patient to take missed dose as soon as remembered and next dose in 24 hours
• Tell patient to immediately notify prescriber of dizziness, arm or leg swelling, difficulty breathing, hives, or rash
• Instruct patient to avoid alcohol and OTC products unless directed by prescriber
• Advise patient to comply in all areas of medical regimen: diet, exercise, stress reduction, smoking cessation, product therapy; to notify prescriber of irregular heartbeat, shortness of breath, swelling of feet, face, and hands, severe dizziness, constipation, nausea, hypotension; use nitroglycerin when angina is severe
• Teach patient to use as directed even if feeling better; may be taken with other cardiovascular products (nitrates, b-blockers)
• Suggest taking amlodipine with food to reduce GI upset
• Advise patient to routinely have blood pressure checked for possible hypotension
• Inform patient to Avoid tasks that require alertness, motor skills until response to drug is established
• Tell patient to Do not ingest grapefruit products or alcohol
Treatment of Overdose:
Defibrillation, b-agonists, IV calcium inotropic agents, diuretics, atropine for AV block, vasopressor for hypotension
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