Warnings for Inderal XL
Included as part of the PRECAUTIONS section.
Precautions for Inderal XL
Cardiac Ischemia After Abrupt Discontinuation
Following abrupt discontinuation of therapy with beta-blockers, exacerbations of angina pectoris and myocardial infarction have occurred.
When discontinuing chronically administered INDERAL XL, particularly in patients with ischemic heart disease, gradually reduce the dose over a period of 1-2 weeks and monitor the patients. If angina markedly worsens or acute coronary insufficiency develops, promptly resume therapy, at least temporarily and take other measures appropriate for the management of unstable angina. Warn patients against interruption or discontinuation of therapy without physician’s advice.
Because coronary artery disease is common and may be unrecognized, avoid abrupt discontinuation of INDERAL XL therapy even in patients treated only for hypertension.
Cardiac Failure
Beta-blockers, like INDERAL XL, can cause depression of myocardial contractility and may precipitate heart failure and cardiogenic shock. If signs or symptoms of heart failure develop, treat the patient according to recommended guidelines. It may be necessary to lower the dose of INDERAL XL or to discontinue it.
Maintain During Major Surgery
Chronically administered beta-blocking therapy, including INDERAL XL, should not be routinely withdrawn prior to major surgery; however, the impaired ability of the heart to respond to reflex adrenergic stimuli may augment the risks of general anesthesia and surgical procedures.
Hypoglycemia
Beta-blockers may prevent early warning signs of hypoglycemia, such as tachycardia, and increase the risk for severe or prolonged hypoglycemia at any time during treatment, especially in patients with diabetes mellitus or children and patients who are fasting (i.e., surgery, not eating regularly, or are vomiting). If severe hypoglycemia occurs, patients should be instructed to seek emergency treatment.
Thyrotoxicosis
INDERAL XL may mask clinical signs of hyperthyroidism, such as tachycardia. Avoid abrupt withdrawal of beta-blockade, which may precipitate a thyroid storm.
Bradycardia
Bradycardia, including sinus pause, heart block, and cardiac arrest have occurred with the use of INDERAL XL. Patients with first-degree atrioventricular block, sinus node dysfunction, or conduction disorders (including Wolff-Parkinson-White) may be at increased risk. The concomitant use of beta-adrenergic blockers and non-dihydropyridine calcium channel blockers (e.g., verapamil and diltiazem), digoxin or clonidine increases the risk of significant bradycardia. Monitor heart rate and rhythm in patients receiving INDERAL XL. If severe bradycardia develops, reduce or stop INDERAL XL.
Reduced Effectiveness Of Epinephrine In Treating Anaphylaxis
Beta-adrenergic blocker-treated patients treated with epinephrine for a severe anaphylactic reaction may be less responsive to the typical doses of epinephrine. In these patients, consider other medications (e.g., intravenous fluids, glucagon).
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenesis
In dietary administration studies in which mice and rats were treated with propranolol HCl for up to 18 months at doses of up to 150 mg/kg/day, there was no evidence of drug-related tumorigenesis. On a body surface area basis, this dose in the mouse and rat is, respectively, about equal to and about twice the MRHD of 640 mg propranolol HCl.
Mutagenesis
Based on differing results from Ames tests performed by different laboratories, a genotoxic effect of propranolol HCl is equivocal in bacteria (S. typhimurium strain TA 1538).
Impairment Of Fertility
Propranolol effects on fertility are also equivocal. No effects on fertility were reported in a study with both male and female rats exposed to propranolol HCl in their diets at concentrations of up to 0.05% (about 50 mg/kg body weight and less than the MRHD), from 60 days prior to mating and throughout pregnancy and lactation for 2 generations. Another study in rats receiving oral propranolol (7.5 and 15 mg/kg for 60 days) reported decreased sperm motility, increased sperm abnormalities and decreased testosterone; all effects were fully reversible within 60 days of propranolol discontinuation. A separate study in male mice receiving oral propranolol (10 or 15 mg/kg body weight) in water once daily reported both doses impaired spermatogenesis and reduced sperm motility; fewer females became pregnant and pregnant females had fewer implantation sites and viable fetuses. In addition, when female rabbits were injected with 7 mg/kg propranolol at three-hour intervals (8 times daily is about twice the MHRD), sperm counts in the oviducts were reduced and fewer sperm attached to and penetrated the eggs.
Use In Specific Populations
Pregnancy
Risk Summary
Prolonged experience with propranolol in pregnant women over several decades, based on published interventional and observational studies, has not identified a drug associated risk of major birth defects, miscarriage, or other adverse maternal outcomes. Bradycardia, hypoglycemia, and respiratory depression have been observed with use of beta-blockers, including propranolol, in utero near the time of delivery.
There are inconsistent reports of intrauterine growth restriction with beta-blocker use, including propranolol, during pregnancy. Untreated hypertension during pregnancy can lead to serious adverse outcomes for the mother and the fetus (see Clinical Considerations And Data).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Clinical Considerations
Disease-Associated Maternal And/Or Embryo/Fetal Risk
Hypertension in pregnancy increases the maternal risk for pre-eclampsia, gestational diabetes, premature delivery, and delivery complications (e.g., need for cesarean section, and post-partum hemorrhage) Hypertension increases the fetal risk for intrauterine growth restriction and intrauterine death. Pregnant women with hypertension should be carefully monitored and managed accordingly.
Fetal/Neonatal Adverse Reactions
Propranolol crosses the placenta. Neonates born to mothers who are receiving propranolol during pregnancy, may be at risk for bradycardia, hypoglycemia, and respiratory depression. Monitor neonates exposed to propranolol during pregnancy and manage accordingly.
Data
Animal Data
In a series of reproductive and developmental toxicology studies, propranolol was given to rats by gavage or in the diet throughout pregnancy and lactation. At doses of 150 mg/kg/day, but not at doses of 80 mg/kg/day (equivalent to the maximum recommended human oral daily dose (MRHD) on a body surface area basis), treatment was associated with embryotoxicity (reduced litter size and increased resorption rates) as well as neonatal toxicity (deaths). Propranolol HCl was also administered (in the feed) to rabbits (throughout pregnancy and lactation) at doses as high as 150 mg/kg/day (about 5 times the MRHD). No evidence of embryo or neonatal toxicity was noted.
Lactation
Risk Summary
Propranolol is present in human milk at low levels, but the related risk to a breastfed infant is unknown. There are no data on the effects of propranolol on milk production.
The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for INDERAL XL and any potential adverse effects on the breastfed child from INDERAL XL or from the underlying maternal condition.
Females And Males Of Reproductive Potential
Infertility
Males
Based on the published literature, beta-blockers, including propranolol, may cause erectile dysfunction. In rats, propranolol inhibits spermatogenesis [see Nonclinical Toxicology].
Pediatric Use
Safety and effectiveness of propranolol in pediatric patients have not been established.
Geriatric Use
Clinical studies of INDERAL XL did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Renal Impairment
The exposure to propranolol is increased in patients with renal impairment. Initiate INDERAL XL therapy in patients with impaired renal function at the lowest dose (80 mg) once daily and monitor patients for marked bradycardia and hypotension [see CLINICAL PHARMACOLOGY].
Hepatic Impairment
The exposure to propranolol is increased in patients with hepatic impairment. Initiate INDERAL XL therapy in patients with impaired hepatic function at the lowest dose (80 mg) once daily and monitor patients for marked bradycardia and hypotension [see CLINICAL PHARMACOLOGY].