Salcain 2%/30ml injection, also known as lidocaine, contains the active ingredient lidocaine hydrochloride. It is a local anesthetic that belongs to the group of medications called amino amide. It is used to produce local anesthesia (numb a specific area) and stop pain being felt in the area of the body where it is locally administered. It is also an anti-arrhythmic agent used to control fast or abnormal heartbeats you might experience after a heart attack. Common side effects of this injection are edema, erythema, skin rashes, and headache. Do not use Salcain 2%/30ml injection if you are allergic to lignocaine or any of the other ingredients of this medicine. Do not take this medicine if you have an allergic reaction to any local anesthetic medicines. Before initiating the treatment, inform your doctor if you have heart disease, blood disorders, or kidney or liver diseases. Talk to your doctor before using this medicine if you suffer from a breathing disorder, epilepsy, active inflammation, or infection. This medicine must not be used in the eye. Contact your physician immediately if you begin to experience lightheadedness, numbness of your tongue, or a ringing in your ears after receiving this medicine.