Lignocaine, also known as lidocaine, is a common medication in the medical field. It is known for its ability to numb specific body areas and regulate heart rhythms. It is a standard in many medical procedures due to its effectiveness and rapid action, providing comfort and managing serious conditions.
What Lignocaine Is
Lignocaine is classified as a local anesthetic of the amino amide type. It temporarily blocks nerve signals in a localized area, causing loss of sensation without inducing unconsciousness. It also functions as a Class 1b antiarrhythmic medication, stabilizing the heart’s electrical activity to manage irregular rhythms.
How Lignocaine Works
Lignocaine blocks voltage-gated sodium channels in nerve cell membranes. This prevents sodium ion influx, which is necessary for nerve impulse conduction. This interruption stops pain signals from traveling to the brain, causing localized loss of sensation.
For antiarrhythmic effects, lignocaine acts on sodium channels in cardiac cells, especially in the heart’s Purkinje fibers and ventricular cells. It binds to inactivated sodium channels, common in ischemic or depolarized cardiac tissue. This reduces electrical activity, shortens action potential duration, and increases the refractory period, stabilizing abnormal heart rhythms and preventing conditions like ventricular tachycardia.
Where Lignocaine is Used
Lignocaine is used as a local anesthetic for minor surgical procedures. Dentists use it to numb the mouth and gums before procedures. It is also applied for skin biopsies and minor skin excisions, often with adrenaline to prolong effects and reduce bleeding.
It is used in regional anesthesia, like epidurals, providing pain relief during childbirth or surgery by blocking nerve signals in a larger body area. Beyond anesthesia, lignocaine is given intravenously for certain cardiac arrhythmias. It is effective for ventricular tachycardia and ventricular fibrillation, especially in acute myocardial infarction or digoxin poisoning. This makes it a tool in emergency cardiac care.
Forms of Lignocaine
Lignocaine comes in various forms for different medical needs. Topical preparations (creams, gels, patches, sprays) numb skin or mucous membranes. They are applied for minor skin procedures or to alleviate discomfort from conditions like post-herpetic neuralgia.
Injectable solutions are used for local or regional anesthesia. They come in varying concentrations (typically 1% or 2%) and can be infiltrated into tissues or used for nerve blocks. Intravenous solutions are for cardiac use, allowing precise dosing control when treating arrhythmias. The form chosen depends on the medical application and desired effect.
Potential Side Effects and Precautions
Lignocaine can cause side effects, usually mild and temporary. Common injection site reactions include redness, swelling, or stinging. Less frequent systemic side effects can involve dizziness, drowsiness, confusion, or numbness and tingling beyond the application site.
Rare but serious adverse events include allergic reactions (hives, difficulty breathing). Cardiovascular effects like low blood pressure or irregular heart rate can occur, especially with higher doses or accidental intravenous injection. Central nervous system toxicity (twitching, tremors, seizures) is also a rare but serious concern. Patients should inform medical professionals about allergies or existing medical conditions for safe administration and monitoring.