title XVIII of the Social Security Act, other than a Medicare supplemental policy (as defined in section 1882 of such Act). . (b) Effective date The amendments made by this section shall apply with respect to insurance purchased after the date of the enactment of this Act in taxable years beginning after such date. 303. Special rule for certain medical expenses incurred before establishment of account (a) In general Paragraph (2) of section 223(d) is amended by adding at the end the following new subparagraph: (D) Treatment of certain medical expenses incurred before establishment of account If a health savings account is established during the 60-day period beginning on the date that coverage of the account beneficiary under an HSA-qualified health plan begins, then, solely for purposes of determining whether an amount paid is used for a qualified medical expense, such account shall be treated as having been established on the date that such coverage begins. . (b) Effective date The amendment made by this section shall apply with respect to coverage beginning after the date of the enactment of this Act. 304. Preventive care prescription drug clarification (a) Clarify use of drugs in preventive care Subparagraph (C) of section 223(c)(2) is amended by adding at the end the following: Preventive care shall include prescription and over-the-counter drugs and medicines which have the primary purpose of preventing the onset of, further deterioration from, or complications associated with chronic conditions, illnesses, or diseases. . (b) Effective date The amendment made by this section shall apply to taxable years beginning after December 31, 2017. IV Miscellaneous provisions relating to tax-preferred health accounts 401. FSA and HRA interaction with HSAs (a) Eligible individuals include FSA and HRA participants Subparagraph (B) of section 223(c)(1) is amended— (1) by striking and at the end of clause (ii), (2) by striking the period at the end of clause (iii) and inserting , and , and (3) by inserting after clause