propranolol hydrochloride

propranolol hydrochloride

(proe pran' oh lole)

Apo-Propranolol (CAN), Inderal, Inderal LA, InnoPran XL, Propranolol Intensolol

Pregnancy Category C

Drug classes

Beta-adrenergic blocker (nonselective)

Antianginal

Antiarrhythmic

Antihypertensive

Therapeutic actions

Competitively blocks beta-adrenergic receptors in the heart and juxtoglomerular apparatus, decreasing the influence of the sympathetic nervous system on these tissues, the excitability of the heart, cardiac workload and oxygen consumption, and the release of renin and lowering BP; has membrane-stabilizing (local anesthetic) effects that contribute to its antiarrhythmic action; acts in the CNS to reduce sympathetic outflow and vasoconstrictor tone. The mechanism by which it prevents migraine headaches is unknown.

Indications

·        Hypertension alone or with other drugs, especially diuretics

·        Angina pectoris caused by coronary atherosclerosis

·        Idiopathic hypertrophic subaortic stenosis to manage associated stress-induced angina, palpitations, and syncope

·        Cardiac arrhythmias, especially supraventricular tachycardia, and ventricular tachycardias induced by digitalis or catecholamines

·        Prevention of reinfarction in clinically stable patients 5–21 days after MI

·        Pheochromocytoma, an adjunctive therapy after treatment with an alpha-adrenergic blocker to manage tachycardia before or during surgery or if thepheochromocytoma is inoperable

·        Prophylaxis for migraine headache

·        Treatment of essential tremor, familial or hereditary

·        Unlabeled uses: Recurrent GI bleeding in cirrhotic patients, schizophrenia, tardive dyskinesia, acute panic symptoms, anxiety, CHF

Contraindications and cautions

·        Contraindicated with allergy to beta-blocking agents, sinus bradycardia, second- or third-degree heart block, cardiogenic shock, CHF, bronchial asthma,bronchospasm, COPD, pregnancy (neonatal bradycardia, hypoglycemia, and apnea, and low birth weight with long-term use during pregnancy), lactation.

·        Use cautiously with hypoglycemia and diabetes, thyrotoxicosis, hepatic dysfunction.

Available forms

ER capsules—60, 80, 120, 160 mg; tablets—10, 20, 40, 60, 80, 90 mg; SR capsules—60, 80, 120, 160 mg; injection—1 mg/mL; oral solution—4, 8 mg/mL; concentrated oral solution—80 mg/mL

Dosages

ADULTS

Oral

·        Hypertension: 40 mg regular propranolol bid or 80 mg SR daily initially; usual maintenance dose, 120–240 mg/day given bid or tid or 120–160 mg SR daily (maximum dose, 640 mg/day).

·        Angina: 80–320 mg/day divided bid, tid, or qid or 80 mg SR daily initially; gradually increase dosage at 3- to 7-day intervals; usual maintenance dose, 160 mg/day (maximum dose, 320 mg/day).

·        IHSS: 20–40 mg tid or qid or 80–160 mg SR daily.

·        Arrhythmias: 10–30 mg tid or qid.

·        MI: 180–240 mg/day given tid or qid (maximum dose, 240 mg/day).

·        Pheochromocytoma: Preoperatively, 60 mg/day for 3 days in divided doses; inoperable tumor, 30 mg/day in divided doses.

·        Migraine: 80 mg/day daily (SR) or in divided doses; usual maintenance dose, 160–240 mg/day.

·        Essential tremor: 40 mg bid; usual maintenance dose, 120 mg/day (maximum dose 320 mg/day)

Parenteral

WARNING: IV dose is markedly less than oral because of first-pass effect with oral propranolol.

·        Life-threatening arrhythmias: 1–3 mg IV with careful monitoring, not to exceed 1 mg/min; may give second dose in 2 min, but then do not repeat for 4 hr.

PEDIATRIC PATIENTS

Safety and efficacy not established.

Pharmacokinetics

Route	Onset	Peak	Duration
Oral	20–30 min	60–90 min	6–12 hr
IV	Immediate	1 min	4–6 hr

Metabolism: Hepatic; T_1/2: 3–5 hr; 8–11 hr (SR form)

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

IV facts

Preparation: No further preparation is needed.

Infusion: Inject directly IV or into tubing of running IV; do not exceed 1 mg/min.

Adverse effects

·        Allergic reactions: Pharyngitis, erythematous rash, fever, sore throat, laryngospasm, respiratory distress

·        CNS: Dizziness, vertigo, tinnitus, fatigue, emotional depression, paresthesias, sleep disturbances, hallucinations, disorientation, memory loss, slurred speech

·        CV: Bradycardia, CHF, cardiac arrhythmias, sinoatrial or AV nodal block, peripheral vascular insufficiency, claudication, CVA, pulmonary edema,hypotension

·        Dermatologic: Rash, pruritus, sweating, dry skin

·        EENT: Eye irritation, dry eyes, conjunctivitis, blurred vision

·        GI: Gastric pain, flatulence, constipation, diarrhea, nausea, vomiting, anorexia, ischemic colitis, renal and mesenteric arterial thrombosis, retroperitoneal fibrosis, hepatomegaly, acute pancreatitis

·        GU: Impotence, decreased libido, Peyronie's disease, dysuria, nocturia, frequency

·        Musculoskeletal: Joint pain, arthralgia, muscle cramp

·        Respiratory: Bronchospasm, dyspnea, cough, bronchial obstruction, nasal stuffiness, rhinitis, pharyngitis

·        Other: Decreased exercise tolerance, development of ANAs, hyperglycemia or hypoglycemia, elevated serum transaminase, alkaline phosphatase, and LDH

Interactions

Drug-drug

·        Increased effects with verapamil

·        Decreased effects with indomethacin, ibuprofen, piroxicam, sulindac, barbiturates

·        Prolonged hypoglycemic effects of insulin

·        Initial hypertensive episode followed by bradycardia with epinephrine

·        Increased first-dose response to prazosin

·        Increased serum levels and toxic effects with lidocaine, cimetidine

·        Increased serum levels of propranolol and phenothiazines, hydralazine if the two drugs are taken concurrently

·        Paradoxical hypertension when clonidine is given with beta-blockers; increased rebound hypertension when clonidine is discontinued in patients on beta-blockers

·        Decreased serum levels and therapeutic effects with methimazole, propylthiouracil

·        Decreased bronchodilator effects of theophyllines

·        Decreased antihypertensive effects with NSAIDs (ie, ibuprofen, indomethacin, piroxicam, sulindac), rifampin

Drug-lab test

·        Interference with glucose or insulin tolerance tests, glaucoma screening tests

Nursing considerations

Assessment

·        History: Allergy to beta-blocking agents, sinus bradycardia, second- or third-degree heart block, cardiogenic shock, CHF, bronchial asthma,bronchospasm, COPD, hypoglycemia and diabetes, thyrotoxicosis, hepatic dysfunction, pregnancy, lactation

·        Physical: Weight, skin color, lesions, edema, T; reflexes, affect, vision, hearing, orientation; BP, P, ECG, peripheral perfusion; R, auscultation; bowel sounds, normal output, liver evaluation; bladder palpation; LFTs, thyroid function tests; blood and urine glucose

Interventions

·        WARNING: Do not discontinue drug abruptly after long-term therapy (hypersensitivity to catecholamines may have developed, causing exacerbation of angina, MI, and ventricular arrhythmias). Taper drug gradually over 2 wk with monitoring.

·        WARNING: Ensure that alpha-adrenergic blocker has been given before giving propranolol when treating patients with pheochromocytoma; endogenouscatecholamines secreted by the tumor can cause severe hypertension if vascular beta receptors are blocked without concomitant alpha blockade.

·        Consult with physician about withdrawing drug if patient is to undergo surgery (withdrawal is controversial).

·        Provide continuous cardiac and regular BP monitoring with IV form. Change to oral form as soon as possible.

·        Give oral drug with food to facilitate absorption.

Teaching points

·        Take this drug with meals. Do not discontinue the medication abruptly; abrupt discontinuation can cause a worsening of your disorder.

·        If you have diabetes, the normal signs of hypoglycemia (tachycardia) may be blocked by this drug; monitor your blood or urine glucose carefully; eat regular meals, and take your diabetic medication regularly.

·        You may experience these side effects: Dizziness, drowsiness, light-headedness, blurred vision (avoid driving or performing hazardous tasks); nausea, loss of appetite (eat frequent small meals); nightmares, depression (request change of your medication); sexual impotence.

·        Report difficulty breathing, night cough, swelling of extremities, slow pulse, confusion, depression, rash, fever, sore throat.

Adverse effects in Italic are most common; those in Bold are life-threatening.