Lidocaine - instructions for use, dose, side effects, contraindications

Lidocaine in chemical structure refers to acetanilide derivatives. Has a pronounced local anesthetic and antiarrhythmic (lb class) action. The local anesthetic effect is due to the inhibition of nerve conduction by blocking the sodium channels in nerve endings and nerve fibers. By its anesthetic action lidocaine significantly (2-6 times) exceeds procaine; the action of lidocaine develops faster and lasts longer - up to 75 minutes, while with simultaneous application with epinephrine - more than 2 hours.With topical application dilates blood vessels, does not have a locally irritating effect.

Antiarrhythmic properties of lidocaine are due to its ability to stabilize the cell membrane, block sodium channels, increase the permeability of membranes for potassium ions. Virtually without affecting the electrophysiological state of the atria, lidocaine accelerates repolarization in the ventricles, depresses the IV depolarization phase in Purkinje fibers (diastolic depolarization phase), reducing their automatism and duration of action potential, increases the minimal potential difference at which myofibrils react to premature stimulation. The speed of rapid depolarization (phase 0) does not affect or slightly reduces. Has no significant effect on conduction and contractility of the myocardium (inhibits conductivity only in large, close to toxic doses). Intervals PQ, QRS and QT under its influence on ECG do not change. Negative inotropic effect is also expressed slightly and manifests itself briefly only with the rapid administration of the drug in large doses.

Pharmacokinetics:Time to reach the maximum concentration in the blood plasma after intramuscular injection is 5-15 minutes, with slow intravenous infusion without the initial saturating dose - after 5-6 hours (in patients with acute myocardial infarction - up to 10 hours). Proteins of blood plasma bind 50 - 80% of the drug. It is quickly distributed (T1 / 2 phases of distribution - 6-9 minutes) in organs and tissues with good perfusion, incl. in the heart, lungs, liver, kidneys, then in muscle and adipose tissue. Penetrates through the blood-brain and placental barriers, is secreted with the mother's milk (up to 40% of the concentration in the mother's plasma). Metabolized mainly in the liver (90-95% of the dose) with the participation of microsomal enzymes with the formation of active metabolites - monoethylglycinexylidide and glycinexylidide, having a half-life of 2 h and 10 h respectively. The intensity of metabolism decreases with liver diseases (can be from 50 to 10% of the normal value); if there is a violation of liver perfusion in patients after myocardial infarction and / or with congestive heart failure. Half-life with continuous infusion for 24-48 hours - about 3 hours; if the kidney function is impaired - can increase 2 or more times. It is excreted with bile and kidneys (up to 10% unchanged).Acidification increases the excretion of lidocaine.

Indications:

- Infiltration, conductive, spinal and epidural anesthesia.

- Terminal anesthesia in ophthalmology.

- Prevention of repeated ventricular fibrillation in acute coronary syndrome and repeated paroxysms of ventricular tachycardia (usually within 12-24 hours).

- Ventricular arrhythmias due to glycosidic intoxication.

Contraindications:

- syndrome of weakness of the sinus node; severe bradycardia; atrioventricular blockade of 2 and 3 degrees (with the exception of cases when a probe is inserted to stimulate the ventricles); WPW syndrome; sinoatrial blockade; acute and chronic heart failure (III-IV FK); cardiogenic shock; severe arterial hypotension, Adams-Stokes syndrome;

- hypersensitivity to any of the components of the drug;

- retrobulbar injection to patients with glaucoma;

- pregnancy, breastfeeding (penetrates the placental barrier, excreted in breast milk).

Carefully:

chronic heart failure of II-III degree, arterial hypotension, hypovolemia, atrioventricular blockade of I-II degree, sinus bradycardia,severe hepatic and / or renal failure, severe myasthenia gravis, epileptiform cramps (including in anamnesis).

It is also necessary to take into account the general contraindications to the conduct of a particular type of anesthesia.

Dosing and Administration:

- for infiltration anesthesia apply a 0.5% solution of lidocaine (maximum dose of 400 mg)

- for blockade of peripheral nerves and nerve plexuses 10-20 ml of 1% solution or 5-10 ml of 2% solution (not more than 400 mg).

- for conductive anesthesia apply 1% and 2% solutions (not more than 400 mg).

- for epidural anesthesia 1% and 2% solutions (not more than 300 mg).

- for spinal anesthesia - 3-4 ml of 2% solution (60-80 mg).

- in ophthalmology: 2% solution is instilled in the conjunctival sac by 2 drops 2-3 times at intervals of 30-60 seconds immediately before surgery or examination.

To prolong the action of lidocaine, it is possible to add ex tempore 0.1% of epinephrine solution (1 drop per 5-10 ml of lidocaine solution, but not more than 5 drops for the entire volume of solution).

It is recommended to reduce the dose of lidocaine in elderly patients and patients with liver diseases (cirrhosis, hepatitis) or with reduced hepatic blood flow (chronic heart failure) by 40-50%.

- as an antiarrhythmic drug: intravenously.25 ml of a 10% solution should be diluted with 100 ml of a 0.9% solution of sodium chloride to a lidocaine concentration of 20 mg / ml. This diluted solution is used to administer a loading dose. The introduction begins with a loading dose of 1-1.5 mg / kg (for 2-4 minutes at a rate of 25-50 mg / min) with immediate connection of a constant infusion at a rate of 1-4 mg / min. Due to the rapid distribution (half-life of about 8 minutes), 10-20 minutes after the first dose, the drug concentration in the blood plasma decreases, which may require a repeated bolus administration (against a background of continuous infusion) at a dose of 1 / 2-1 / 3 loading dose, with an interval of 8-10 minutes.

The maximum dose at 1 hour is 300 mg, per day 2000 mg.

Intravenous infusion is usually performed for 12-24 hours with constant ECG monitoring, after which the infusion is discontinued to assess the need for changing antiarrhythmic therapy in the patient.

The rate of excretion of the drug is lowered with heart failure and impaired liver function (cirrhosis, hepatitis), which requires a reduction in the dose and rate of drug administration by 25-50%. With chronic renal failure, dose adjustment is not required.

Side effects:

From the nervous system and sensory organs: euphoria, headache, dizziness, drowsiness, neurotic reactions, confusion, disorientation, convulsions, loss of consciousness, tinnitus, paresthesia, diplopia, photophobia, tremor, trismus facial muscles of the face, numbness of the tongue and mouth mucosa (when used in dentistry ).

From the cardiovascular system: increase or decrease in blood pressure, bradycardia, peripheral vasodilation, collapse, chest pain, bradycardia, cardiac arrest.

Allergic reactions: skin rash, hives, itching, angioedema, anaphylactic shock.

From the digestive system: nausea, vomiting.

Local reactions: with spinal anesthesia - pain in the back, with epidural anesthesia - accidental entry into the subarachnoid space.

Overdose:Symptoms: the first signs of intoxication - dizziness, nausea, vomiting, euphoria, lowering blood pressure, asthenia; then - convulsions of mimic muscles with transition to tonic-clonic convulsions of skeletal muscles, psychomotor agitation, bradycardia, asystole, collapse; when used at birth in a newborn - bradycardia, oppression of the respiratory center, apnea.Treatment: discontinuation of injection, inhalation with oxygen. Symptomatic therapy. With convulsions intravenously administered 10 mg of diazepam. With bradycardia - m-holinoblokatory (atropine), vasoconstrictors (norepinephrine, phenylephrine). Hemodialysis is ineffective.

Interaction:

It is undesirable to combine lidocaine with the following preparations:

- with beta-blockers and cimetidine due to an increased risk of toxic effects;

- with digitoxin - due to the weakening of the cardiotonic effect of digitoxin;

- with kurarepodobnymi drugs - increases muscle relaxation. It is irrational to appoint lidocaine together with aymalin, amiodarone, verapamil or quinidine in connection with the enhancement of the negative inotropic effect.

The joint use of lidocaine and novocainamide (procainamide) can cause CNS excitation, hallucinations.

With intravenous injection of hexenal or thiopental sodium against the background of lidocaine, respiratory depression is possible.

Under the influence of MAO inhibitors (monoamine oxidase), the local anesthetic action of lidocaine is likely to increase. Patients taking MAO inhibitors should not be prescribed lidocaine parenterally.

With the simultaneous administration of lidocaine and polymyxin-B, an increase in the inhibitory effect on neuromuscular transmission is possible. In this case, it is necessary to monitor the function of the patient's breathing.

When used simultaneously with hypnotics or sedatives, it is possible to intensify their inhibitory effect on the central nervous system.

When intravenous lidocaine is administered to patients receiving cimetidine, such undesirable effects as stunnedness, drowsiness, bradycardia, paresthesia, etc. are possible. This is due to the increase in lidocaine in the blood plasma, which is explained by the release of lidocaine from the connection with blood proteins, as well as the slowing of its inactivation in the liver. If the need for combined therapy with these drugs should reduce the dose of lidocaine.

Special instructions:

Care should be taken when carrying out local anesthesia of tissues with high vascularity, an aspiration test is recommended to avoid intravascular injection.

During the treatment period, care must be taken when driving vehicles and engaging in other potentially hazardous activities that require increased concentration and speed of psychomotor reactions.

Form release / dosage:Solution for injection 20 mg / ml and 100 mg / ml.

Packaging:2 ml per ampoule. For 10 ampoules together with the instruction for use, a knife for opening ampoules or a scarifier ampoule in a box or a pack of cardboard.

Storage conditions:

List B.

Store at a temperature not exceeding 30 ° C, protected from light and out of the reach of children.

Shelf life:

3 years.

Do not use after expiry date.

Terms of leave from pharmacies:On prescription

Registration number:P N000979 / 01

Date of registration:22.10.2015/26.10.2015

The owner of the registration certificate:ATOLL, LLC ATOLL, LLC Russia

Manufacturer: & nbsp

VEROPHARM SA Russia

Information update date: & nbsp08.04.2016

Illustrated instructions

Instructions

Lidocaine (Lidocain)