Are naphcon eye drops safe for contact lense use?

Not while in eyes. Do not use any drops that are not specifically labeled a safe to use when your contacts are in your eyes. Naphcon can be used occasionally when the lenses are not in.
Yes. Naphcon is an effective anti-histamine and can be used while wearing the lenses. Be sure that the symptoms you are experiencing are from allergy and not infection. So if the eye hurts, gets more than a little red, or the vision drops, then see your ophthalmologist first after taking out the lens to eliminate a problem.