Lidocaine / Dextrose

1. Health Canada Product Monograph — Lidocaine / Dextrose

• Lidocaine hydrochloride and dextrose injection is used intravenously to treat life-threatening ventricular tachycardia and premature ventricular beats, such as those occurring during heart surgery, cardiac catheterization, a heart attack, or digitalis toxicity.
• It is specifically chosen when fluid restriction is desirable, since it is a premixed, ready-to-use solution.
• This product must be administered by experienced healthcare professionals in a setting where emergency resuscitation equipment and medications are immediately available.

• Lidocaine crosses the placenta.
• This injection should not be given during pregnancy, particularly in early pregnancy, unless the expected benefit outweighs the potential risk.
• Animal studies have not shown evidence of harm to the fetus, and lidocaine has long been used during labour and surgical procedures in pregnancy without reported ill effects, though well-controlled human studies are lacking.

• Lidocaine passes into breast milk in small amounts.
• Based on available data, breastfeeding is not expected to lead to a clinically significant amount of lidocaine accumulating in a nursing infant, though a rare individual sensitivity reaction cannot be entirely ruled out.

• Elderly patients often need a lower dose, particularly if heart or liver function is reduced.
• Doses should be adjusted individually for an older patient's age and body weight, since cardiac output and liver blood flow decline with advancing age and reduce how quickly lidocaine is cleared.

• Health Canada has not authorized use of this product in children, since no pediatric safety or efficacy data have been submitted.

• The usual single intravenous dose is 50 to 100 mg, given at a controlled rate under continuous ECG and blood pressure monitoring; a second dose may be repeated after 10 minutes if the initial dose does not produce the desired effect.
• After the initial injection, a continuous intravenous infusion may be used at a slow, controlled rate in patients whose abnormal heart rhythm tends to recur and who cannot take an oral antiarrhythmic.
• No more than 200 to 300 mg total should be given during any one-hour period.
• Elderly patients and those with congestive heart failure or cardiogenic shock generally need smaller bolus doses.
• The infusion should be stopped as soon as the heart rhythm stabilizes or at the first sign of toxicity; continuing beyond 24 hours is rarely necessary, and patients should be switched to an oral antiarrhythmic for ongoing treatment once appropriate.
• This solution must be given using an infusion pump or a precision volume-control intravenous set, and the administration set should be replaced at least every 24 hours.

If overdose is suspected, seek emergency medical attention immediately or contact your regional Poison Control Centre without delay.

• Overdose or excessively rapid administration can cause central nervous system excitation progressing to numbness around the mouth, tongue numbness, lightheadedness, ringing in the ears, blurred vision, and muscle tremors, followed by drowsiness, seizures, unconsciousness, and possible respiratory arrest.
• Cardiovascular toxicity can include low blood pressure, slow heart rate, heart conduction problems, dangerous heart rhythm disturbances, and cardiovascular collapse leading to cardiac arrest.
• Management includes immediately stopping the infusion, maintaining the airway, giving oxygen, and providing assisted ventilation.
• Persistent seizures may be treated with small intravenous doses of a benzodiazepine, such as diazepam, or an ultra-short-acting barbiturate.
• Intravenous lipid emulsion therapy may be considered for severe toxicity.
• Low blood pressure may be treated with intravenous fluids, elevation of the legs, or medications that raise blood pressure, and a slow heart rate may be treated with medications that counteract the vagus nerve's slowing effect.
• If circulatory arrest occurs, immediate cardiopulmonary resuscitation should be started, since correcting oxygen levels, ventilation, and acid-base balance is critical to limiting ongoing toxicity.

• Dizziness or lightheadedness may occur.
• Numbness or tingling around the mouth may occur.
• Nervousness may occur.
• Drowsiness may occur.
• Blurred vision may occur.
• Nausea or vomiting may occur.
• A sensation of heat, cold, or numbness may occur.
• Tremor may occur.

Serious side effects require immediate discussion with the prescriber or emergency care.

• Seizures (convulsions) can occur with high blood levels of lidocaine.
• Loss of consciousness and respiratory arrest can occur with severe toxicity.
• Slow heart rate, low blood pressure, heart block, or cardiac arrest can occur.
• Dangerous heart rhythm disturbances, including ventricular tachycardia or ventricular fibrillation, can occur.
• Severe allergic reactions, including anaphylactic shock, can occur, causing skin lesions, hives, or swelling.
• Kounis syndrome, a serious allergic reaction that can trigger a heart attack, has been reported with lidocaine.
• A rare blood disorder called methemoglobinemia, in which the blood cannot carry oxygen normally, has been reported, including in newborns and adults.
• Seek urgent medical attention for seizures, fainting, severe shortness of breath, chest pain, or a very slow or irregular heartbeat.

• Use with caution in patients with a slow heart rate (bradycardia).
• Use with caution in patients with severe digitalis toxicity.
• Use with caution in patients with first- or second-degree heart block who do not have a pacemaker.
• Use with caution in patients with low blood potassium (hypokalaemia).
• Use with caution in patients with impaired liver function, since lidocaine is cleared more slowly and can accumulate.
• Use with caution in patients with porphyria.
• Use with caution in patients with epilepsy.
• Use with caution in patients with impaired heart conduction or cardiac decompensation.
• Use with caution in patients with impaired kidney function, particularly with repeated or prolonged dosing.
• Use with caution in patients with severe shock or low blood pressure.
• Use with caution in patients with a posterior diaphragmatic heart attack, who have a higher tendency toward developing heart block.
• Use with caution in patients with a known allergy to corn or corn products, since the dextrose component is derived from corn.

• Contraindicated in patients with known hypersensitivity to lidocaine or any ingredient in the formulation.
• Contraindicated in patients with known hypersensitivity to other amide-type local anesthetics, such as prilocaine, mepivacaine, or bupivacaine.
• Contraindicated in patients with Adams-Stokes syndrome or severe sinoatrial, atrioventricular, or intraventricular heart block.
• Contraindicated in patients with supraventricular arrhythmias.
• Contraindicated in patients with severe depression of heart muscle function.
• May be contraindicated in patients with a known allergy to corn or corn products, due to the dextrose component.

• Amiodarone can raise lidocaine blood levels and increase the risk of toxicity; concurrent use should generally be avoided or requires close monitoring.
• Beta-blockers such as propranolol, metoprolol, and nadolol can reduce the clearance of lidocaine and raise its blood level, so concurrent use should be avoided or closely monitored.
• Cimetidine can significantly raise lidocaine blood levels by reducing its clearance, so concurrent use should be avoided or closely monitored.
• Strong CYP1A2 inhibitors, such as fluvoxamine, can raise lidocaine blood levels and should generally be avoided during lidocaine therapy.
• CYP1A2 inducers, such as phenytoin, may lower lidocaine's effect, potentially requiring a higher dose.
• CYP3A4 inducers, including carbamazepine, phenobarbital, phenytoin, and primidone, may slightly reduce lidocaine blood levels, though usually without needing a dose change.
• Other class Ib antiarrhythmic drugs or other local anesthetics used together with lidocaine have additive toxic effects and should be used cautiously.

• This product is given only by intravenous infusion in a hospital or clinical setting, so food timing does not apply.

• This medication is administered only by a healthcare professional through an intravenous line, under continuous heart monitoring; there is no patient-directed timing relative to meals or time of day.

• Store at room temperature, between 15°C and 25°C.
• This is a single-use solution; any unused portion should be discarded and not reused.

• This medication is given only in a hospital or clinical setting by a healthcare professional while your heart rhythm and blood pressure are continuously monitored.
• Tell your care team about any known allergies, including to corn products, local anesthetics, or lidocaine, before this medication is given.
• Tell your care team about your full medication list, since several common drugs, including some antibiotics, heart medications, and heartburn medications, can raise lidocaine levels in the blood.
• Report any dizziness, ringing in the ears, numbness around the mouth, or visual changes to your care team right away, since these can be early signs of too much medication.
• This medication will be stopped or adjusted by your care team based on your heart rhythm and how you respond to treatment.