What is the mechanism of action of lidocaine as a local anesthetic?

It blocks. The sodium channels that are necessary for nerve conduction thus blocking sensation, and motor muscle movement at higher concentrations, some nerves are harder to block than others.
Nerves are blocked. Lidocaine temporarily blocks initiation and conduction of impulses in nerves. This means that the affected area of the body does not feel sensation. Depending on the concentration of Lidocaine that is used, movement is also partially or completely blocked. Sympathetic nerves are blocked too, which can cause lower blood pressure when Lidocaine is used in epidural anesthesia.

Related Questions

What are the side effects of "lignocaine (lidocaine)" local anesthetic?

Few side effects. When Lidocaine is injected into an area (such as around a tooth) to numb it, there are usually no side effects. If Epinephrine is added to lidocaine, it may cause a rapid heart beat or a rise in blood pressure. If Lidocaine is given IV to treat an abnormal heart rhythm, it may briefly cause ringing in the ears or a feeling of dizziness. Read more...
Dose. At small doses, not really many. At toxic doses, can see seizure or heart arrythmia. A careful practitioner can use this drug very safely and effectively and recognize signs of trouble early. Other side effects depend on area being blocked or additives (epinephrine, preservative). Read more...

I was wondering what are the side effects of "lignocaine (lidocaine)" local anesthetic?

Usually none. If Lidocaine is absorbed into the blood stream at low doses, it may cause ringing in the ears, metallic taste in the mouth, and other temporary side effects. High doses of Lidocaine absorbed into the blood stream can lead to heart and central nervous system problems. Read more...

Will lumbar epidural shots containing lidocaine mylocaine and prilocaine with a local anesthetic show a false positive on a urine drug test?

There are. accounts that it could show up as a false positive for cocaine on an immunoassay urine drug screen. However, you could request a GC/MS to be performed, which would definitively rule out the presence of cocaine.

The best answer to your question is its extremely unlikely and not supposed to, but in theory could happen. Read more...
No. The drugs are not of the same chemical structure targeted by the test. But numerous claims of positive cocaine urine test after seeing a dentist or having epidural has been made in the past. Read more...