Nafcillin is initial therapy for usually suspected penicillin G resistant staphylococcal or

streptococcal infections. Initially make use of parenteral therapy in severe infections as well

as change it to oral therapy if condition warrants.

As nafcillin can lead to thrombophlebtis at the site of injection, especially in elderly patients,

administering parenterally only for short term is preferred; change it to oral administration as

indicated clinically.