I am allergic to keflex & penicillin. is neosporin still ok to use on my skin?

Yes: Neither of your allergies are related to neosporin.

Yes: Keflex is a cephalosporin and a "cousin" to penicillin. Neosporin contains neomycin and Polymyxin B and bacitracin. These are chemically not related to Keflex or penicillin. There should be no reaction. Some people will go on to develop allergic reactions to neomycin.

Neosporin: People have a tendency to assume that neosporin does not cause side effects because it is a widely available and frequently used nonprescription product. However, this is simply not the case. In fact, many healthcare providers now recommend that people avoid products with neomycin (including neosporin), as neomycin is more likely than most other antibiotics to cause allergic reactions.