Most offices have a Office First Aid kit that contains the basic bandaid / aspirin stuff so you shouldn't need to use your own such supplies regularly even for your own needs when at the office. Homes are usually likewise supplied. In terms of FAK supplies the only thing that I really bring to the table at the office is knowledge on how and when to use these items and an awareness of what is on hand and where it is. If it isn't supplied where you work you should remind the employeer of the appropriate OSHA requirements and suggest that they get a reasonable FAK.

I am an EMT-B so I also have a jump kit for duty use that contains some items not usually found in the office FAK like gloves, cpr mask, airways, splints, Stethescope, BP cuff, etc... that require some skill to make them useful. I won't be lending them out but if need be I will - and have - put them to use. Same goes for my other EDC tools. If someone needs a knife I will gladly cut open whatever package / box that they need opened. If someone needs a flashlight I will gladly shine some light into the dark corner under the desk while they use both hands to fix the errant PC or fishout the network cable from under the cube wall. If they need a screw-driver or similar I will stand by as they use it and retrieve it when they are done. If they put it down I pick it up. This way I get to be very helpful and the tools never leave my sight. I have had my tools damaged on occasion but usually, since I am standing there when they damage it, they look sheepish and volunteer to replace it. I gladly take them up on the offer and when they bring in the replacement I give them the damaged tool. For example, once a coworker borrowed my leatherman wave to "fix" a noisy fan in a power supply. When he grabbed a live wire with the pliers there was a loud arc and some of the tip of the jaws of the leatherman was vaporized. He got quite a jolt as well. After tending to his medical condition - only scorched his fingers no cross-body current but I took a full set of vitals and helped him calm down. He offered to replace the damaged wave. A week later the new wave arrived and when I gave him the damaged one he was surprised and pleased to have such a useful tool with only minor damage. He has carried it since.