What are the risks of Local Anesthetic Medicines?
While local anesthetics are widely and successfully used to provide pain relief, they are not without potential problems. In addition to the numbing effect they have on nerves, they also have actions on the brain and heart. If too much local anesthetic enters the circulation, it can cause a convulsion or a disturbance of heart rhythm. For this reason there are limits concerning how much local anesthetic medication is safe to administer. In addition, epinephrine (adrenaline) is often added to the local anesthetic solution because it constricts blood vessels, thus reducing blood flow to the area, thus the slowing absorption and lowering the blood levels of the local anesthetic drug. Many patients think themselves to be allergic to local anesthetics because of the way the epinephrine makes them feel (anxious, apprehensive, heart racing). However, such symptoms are not signs of a true drug allergy but rather just the actions of small amounts of epinephrine that have gotten into their syste
