Bretylium Tosylate

Bretylium Tosylate is a prescription medication used to treat the symptoms of ventricular arrhythmia. 

• Bretylium Tosylate is available under the following different brand names: Bretylium.

Common side effects of Bretylium Tosylate include:

• Stomach pain, and
• Vomiting

Serious side effects of Bretylium Tosylate include:

• Hives,
• Difficulty breathing,
• Swelling of the face, lips, tongue, or throat,
• Rash,
• Itching,
• Red, swollen, blistered, or peeling skin with or without fever,
• Wheezing,
• Tightness in the chest or throat,
• Trouble swallowing or talking,
• Unusual hoarseness,
• Dizziness,
• Fainting,
• Severe headache,
• New or worsening fast or irregular heart rate, and
• Fever

Rare side effects of Bretylium Tosylate include:

• None 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out. 

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult dosage

Solution for injection

• 500 mg/10 mL (50 mg/mL single-dose vial)

Ventricular Arrhythmia

Adult dosage

• Immediately life-threatening ventricular arrhythmias (. g, VF, unstable VT)
• Other usual cardiopulmonary resuscitative procedures, including electrical cardioversion, should be used before and following the injection by good medical practice.
• Undiluted solution: 5 mg/kg Intravenous by rapid injection; if arrhythmia persists, may increase the dose to 10 mg/kg and repeat as needed.
• Diluted solution for continuous suppression: 1-2 mg/min Intravenous; alternatively, 5-10 mg/kg Intravenous over at least 8 min every 6 hours
• Other ventricular arrhythmias
  • Intravenous
    • Use diluted solution.
    • 5-10 mg/kg Intravenous over at least 8 min; may repeat dose at 1- to 2-hr intervals if arrhythmia persists.
    • Maintenance: 5-10 mg/kg Intravenous over at least 8 min every 6 hours; alternatively, 1-2 mg/min Intravenous continuous infusion
  • Intramuscular
    • Use an undiluted solution.
    • 5-10 mg/kg IM; may repeat dose at 1- to 2-hr intervals if arrhythmia persists.
    • Maintenance: 5-10 mg/kg Intramuscular every 6-8hours
    • Switch the oral antiarrhythmic agent as soon as possible for continued maintenance therapy.
  • Geriatric dosage
    • Immediately life-threatening ventricular arrhythmias (. g, VF, unstable VT)
    • Other usual cardiopulmonary resuscitative procedures, including electrical cardioversion, should be used before and following the injection by good medical practice.
    • Undiluted solution: 5 mg/kg IV by rapid injection; if arrhythmia persists, may increase the dose to 10 mg/kg and repeat as needed.
    • Diluted solution for continuous suppression: 1-2 mg/min Intravenous; alternatively, 5-10 mg/kg Intravenous over at least 8 min every 6 hours 
• Other ventricular arrhythmias (Intravenous)
  • Use diluted solution.
    • 5-10 mg/kg Intravenous over at least 8 min; may repeat dose at 1- to 2-hr intervals if arrhythmia persists.
    • Maintenance: 5-10 mg/kg Intravenous over at least 8 min every 6 hours; alternatively, 1-2 mg/min Intravenous continuous infusion
• Other ventricular arrhythmias (Intramuscular)
  • Use an undiluted solution.
    • 5-10 mg/kg Intramuscular; may repeat dose at 1- to 2-hour intervals if arrhythmia persists.
    • Maintenance: 5-10 mg/kg Intramuscular every 6-8 hours
    • Switch the oral antiarrhythmic agent as soon as possible for continued maintenance therapy.

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Bretylium Tosylate has severe interactions with no other drugs.
• Bretylium Tosylate has serious interactions with the following drug:
  • digoxin
• Bretylium Tosylate has moderate interactions with at least 91 other drugs.
• Bretylium Tosylate has minor interactions with no other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• Digitalis-induced arrhythmias

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Bretylium Tosylate?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Bretylium Tosylate?”

Cautions

• Hypotension
  • Administration regularly results in postural hypotension, subjectively recognized by dizziness, lightheadedness, vertigo, or faintness.
  • Some degree of hypotension is present in approximately 50% of patients while they are supine.
  • Hypotension may occur at doses lower than those needed to suppress arrhythmias.
  • Keep patients in a supine position until tolerance to the hypotensive effect develops; tolerance occurs unpredictably but may be present after several days.
  • Patients aged above 65 years may be at increased risk of developing orthostatic hypotension, especially if recommended Intravenous infusion is exceeded.
  • Hypotension with supine systolic pressure above 75 mm Hg need not be treated unless there are associated symptoms.
  • If supine systolic pressure falls below 75 mm Hg, dopamine or norepinephrine infusion may be used to raise blood pressure.
  • When catecholamines are administered, use a dilute solution, and closely monitor blood pressure (pressure affects catecholamines enhanced by bretylium)
  • Volume expansion with blood or plasma and correction of dehydration should be carried out where appropriate.
• Transient hypertension
  • Bretylium causes an initial norepinephrine release from adrenergic postganglionic nerve terminals.
  • Transient hypertension or increased frequency of premature ventricular contractions and other arrhythmias may occur in some patients, especially after too vigorous a dosing.
• Fixed cardiac output.
  • Avoid use in patients with fixed cardiac output (. g, severe aortic stenosis or pulmonary hypertension) since severe hypotension may result from a fall in peripheral resistance without a compensatory increased cardiac output
  • If survival is threatened by the arrhythmia, bretylium may be used, but vasoconstrictive catecholamines should be given promptly if severe hypotension occurs.
• Hyperthermia
  • Hyperthermia, characterized by a temperature excess of 106°F, is reported; temperature rise can begin within 1 hour or later after administration and peak within 1-3 days.
  • If suspected or diagnosed, discontinue bretylium and institute treatment immediately.
• Drug interaction overview
  • Digoxin
    • Initial release of norepinephrine caused by bretylium may aggravate digitalis toxicity.
    • When a life-threatening cardiac arrhythmia occurs in a digitalized patient, bretylium should be used only if the etiology of the arrhythmia does not appear to be digitalis toxicity and other antiarrhythmic drugs are not effective.
    • Avoid simultaneous initiation of therapy with digitalis glycosides and bretylium.
  • Monoamine oxidase inhibitors (MAOIs)
    • Bretylium produces the release of catecholamines from nerve endings.
    • This increased catecholamine release is potentiated by MAOIs.
  • Catecholamines
    • If catecholamines (. e, dopamine, norepinephrine) are administered to treat systolic blood pressure below 75 mm Hg, a dilute solution should be used, and blood pressure monitored closely because the pressure effects of the catecholamines are enhanced by bretylium.

Pregnancy and Lactation

• Unknown whether bretylium can cause fetal harm when administered to pregnant women or can affect reproduction capacity.
• Administer during pregnancy only if needed.
• Animal reproduction studies have not been conducted.
• Lactation
  • Data are not available.