Typically if your friend is only riding as a passenger and not driving your vehicle they do not need to be added to your policy as a driver. If you take turns driving the vehicle to work then you should contact your insurance company to see if they cover the passenger and part time driver under your current policy or if you would need to add her to it.

If you are worried about medical coverage, generally, your insurance would cover your passenger up to your limits. In most states, your passenger medical expenses would be covered by bodily injury liability, uninsured motorist coverage or personal injury protection (pip) coverage, depending on what type of accident occurred and who was at fault. But again check with your insurance company to make sure your limits and coverages will cover your passenger properly.