Negative Predictive Value and NIC of Beta-Lactam Antibiotics.

The Negative Predictive Value and Non-irritant Skin Testing Concentrations of Beta-Lactam Containing Antibiotics Other Than Penicillin.

The researchers are trying to evaluate how much medication is required for allergy skin testing and to determine the likelihood that patients with a negative test truly don't have an allergy to the tested drug of skin testing to commonly used antibiotics.

This study will be a prospective study to accurately determine the negative predictive value of skin testing with beta lactam containing antibiotics other than penicillin .

It is hypothesized that the concentrations that should be used for beta lactams are actually much lower than previously recommended and that the higher incidence of identifiable beta lactam induced allergic reactions during anesthesia in the past may be due to irritation of the skin rather than a true allergic reaction (false positives).

Inclusion Criteria:

• All adults > or = to 18 y/o undergoing surgery

Exclusion Criteria:

• Minors under the age of 18 y/o, Adults unable to consent, or those Adults with previous allergic reaction history during previous surgeries.