Lidocaine can cause side effects such as blurred vision, confusion, dizziness or lightheadedness upon standing, drowsiness, lethargy, seizures, shakiness in the limbs, chest pain, coughing, breathing difficulties or irregularities, difficulty swallowing, increased heart rate, no blood pressure or pulse, clammy skin, hives, rashes, pale or blue lips or nails and swelling of facial features, according to Mayo Clinic. Most of these side effects are minor and do not require medical treatment, and they typically go away once the body adjusts to the treatment.
Although most of the side effects of lidocaine are minor, there are a few side effects that should be monitored by a health care professional if they continue and do not improve after some time, as stated by Mayo Clinic. These side effects include coldness or numbness, ringing or buzzing in the ears, double vision, hearing loss and a heat sensation.
Some patients may be allergic to the ingredients contained in lidocaine, as detailed by WebMD. A doctor should be aware of the patient's possible allergies before administering the medication. Patients who should be particularly careful are those who have a history of heart, lung or breathing issues, kidney or liver disease or epilepsy, as well as those using cimetidine or beta blockers.