If you have a General Purpose FSA, eligible medical, dental and vision expenses for you and your tax dependents, like:
Copayments and coinsurance
Over-the-counter drugs for which you have a prescription
Contact lenses and eyeglasses
If you have a Limited Purpose FSA, eligible preventive pharmacy coinsurance, dental and vision expenses for you and your tax dependents until you meet your deductible, and then eligible medical expenses too.