In patients with a known sulfite allergy, it is crucial to avoid local anesthetic formulations that contain sulfite preservatives.

- Epinephrine-containing local anesthetics usually have sodium metabisulfite added as a preservative to prevent oxidation of the vasoconstrictor.
- Patients with sulfite allergies can have allergic reactions to these preservatives.
- Therefore, Lidocaine with epinephrine (Option 1) should be avoided in such patients because it contains sulfites.
- In contrast, plain local anesthetics without vasoconstrictors (like plain bupivacaine, procaine without vasoconstrictor, or mepivacaine without vasoconstrictor) do not contain sulfite preservatives and are generally safe to use.

Key Points:
- Sulfite preservatives are primarily found in local anesthetics containing vasoconstrictors like epinephrine.
- Patients with sulfite allergy can experience severe hypersensitivity reactions to these preservatives.
- Therefore, use preservative-free, plain local anesthetics in these patients.

Reference: Malamed, D. M. Handbook of Local Anesthesia, 6th Edition, Chapter 10 / Page 150