What is the most significant adverse reaction to lignocaine?

The most significant adverse reaction to lignocaine is tied to the potential for toxicity, particularly when the drug is inadvertently injected into a vein. When lignocaine is administered, it is expected to be given into specific areas such as tissues for local anesthesia. If injected directly into a blood vessel, the drug can rapidly enter the systemic circulation, leading to elevated blood levels and increasing the risk of central nervous system and cardiovascular toxicity, which can manifest as seizures, arrhythmias, or even cardiac arrest.

Toxicity is a critical concern when using lignocaine, as it can adversely affect multiple organ systems, highlighting the importance of proper technique during administration. While hypersensitivity reactions can occur, they are relatively rare compared to the more immediate and severe effects of toxicity associated with accidental intravenous injection.

Ensuring safe injection practices and monitoring for toxicity signs is vital for preventing serious complications when using local anesthetics like lignocaine.