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International generic name
Lidocaine
Drug form and composition
Solution for injection. One ampoule of 2 ml (2%) contains 40 mg (20 mg/ml) Lidocaine
hydrochloride. One ampoule of 10 ml (0.5%, 1% or 2%) contains 50 mg (5 mg/ml), 100
mg (10 mg/ml), 200 mg (20 mg/ml) Lidocaine hydrochloride respectively.
Indications
Lidocaine hydrochloride is used in different types local anesthesia in surgery,
stomatology, urology, cardiology, ophthalmology, otorhinolaryngology, as well as
in different invasive diagnostic manipulations. Preventively Lidocain is used in
conditions predisposing to cardiac rhythm disorders; in patients with ventricular
arrhythmias, particularly those accompanying a myocardial infarction, digitalis
intoxication, and cardiac surgery.
Dosage and administration
In patients with cardiac rhythm disorders Lidocain is applied jet intravenously
in initial loading dose 1-1.5 mg per kg body weight (mean dose 75-100 mg in adults)
injected within 2 minutes. The same dose could be repeated in 10-minutes interval
or 50 mg are injected jet intravenously within a minute. The latter dose is repeated
4 times in 5-10-minutes intervals. In order to maintain a therapeutic plasma concentration,
the preparation is applied as a continuous infusion with rate 1-4 mg per kg body
weight - up to total 24 hours dose 1.5-3 g within 2-3 days. In infiltration anesthesia
total solution volume should not exceed 50-100 ml, 0.5% solution, depending on the
type of surgery; in conduction and epidural anesthesia - 20-30 ml. Maximal volume
should not exceed 500 ml, 0.5% solution or 250 ml, 1% solution.
Contraindications
Hypersensitivity to Lidocain; Adams-Stock’s syndrome; high degree AV - or SA
- block.
Special warnings and precautions
Lidocain should not be used in severe heart failure; hepatal function disorders
and severe liver diseases, particularly in cases with disturbed liver blood circulation;
severe renal diseases and renal function disorders; shock and hypovolemia; incomplete
heart block or sinus node bradycardia; WPW-syndrome; in newborns, as a danger of
life-threatening side effects exists, including protracted convulsion. Cross-sensitivity
reactions with other amide anesthetics were described. Lidocain should not be used
in pregnant women, as it and its metabolites pass the placenta, which may lead to
newborn's central nervous system depression, bradycardia etc. As the preparation
may lead to blood pressure reduction and somnolence, it should be avoided in drivers
and machinery-operating persons until the preparation effect disappears.
Drug interactions
In concomitant application of other antiarrhythmic medicines the Lidocain effect
is enhanced. In concomitant application of anticonvulsuve preparations and hydantoin
a depression of cardiac function is possibly to appear. In combined treatment with
β-adrenoreceptor blockers (propranolol, atenolol, etc.) Lidocain plasma concentration
is increased and a risk of intoxication exists. In high dosage and particularly
in intravenous application of Lidocain together with neuro-muscular blockers the
effect of both medicines is potentiated. Adrenalin, applied together with Lidocain,
leads to prolongation of the local anesthesia.
Adverse reactions
In patients with ventricular dysfunction rarely conduction disorders were seen.
Administration of high dose Lidocain leads to the blood pressure decrease, rhythm
disorders, heart block or heart arrest, and respiratory insufficiency. In therapeutic
plasma concentrations or plasma levels slightly exceeding the therapeutic (1.5 -
6 mg/ml) insomnia, anxiety, dizziness, somnolence, emotional disorders, and visual
disorders may appear.
Pharmacological mechanisms
Lidocain is a local anesthetic, belonging to the group of amides, possessing
fast analgesic and antiarrhythmic effects. The effects of the preparation are due
to a decrease of sensitivity of the pain receptors, retardation of the peripheral
nerve conduction, and a prominent membrane-stabilization effect. In the place of
application Lidocain inhibits the calcium ion influx, as well as (in lower degree)
potassium ion reflux trough the neuron membrane, inhibiting depolarization and permeability
of the latter. In the cardiac muscle the preparation exerts a selective antiarrhythmic
activity, particularly in ventricular arrhythmias. It slightly depresses myocardial
contractility, which make possibly to use the preparation in patients with heart
failure. As Lidocain is fast metabolized by the liver microsomes its effect is of
short duration. For this reason an intravenous application is recommended.
Supplied
50 ampoules of 10ml (0.5%, 1%, and 2%). 10 or 100 ampoules of 2 ml (40 mg).
Expiry
5 years
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