Although lidocaine is FDA-approved and generally regarded as safe, allergic reactions and overdoses are possible. As with most drugs, no two people will be affected in exactly the same way. Different people will have different levels of sensitivity to most drugs, which may affect the required dosage. With that in mind, it's always wise to closely follow the instructions listed on the packaging and to notify your physician if you notice anything odd after beginning to use a new medicine.
When using lidocaine you should notify your doctor immediately if you experience any of the following symptoms:
- Blurred vision
- Unusual heat sensations
- Ringing in ears
Contact emergency services if you experience the signs of an allergic reaction which can include: trouble breathing; swelling of face, throat, and mouth; hives.