<Page> Exhibit 12 Abbott Laboratories Computation of Ratio of Earnings to Fixed Charges (Unaudited) (DOLLARS IN MILLIONS EXCEPT RATIOS) <Table> <Caption> Six Months Ended June 30, 2003 ---------------- Net Earnings $1,048 Add (deduct): Taxes on earnings 424 Capitalized interest cost, net of amortization 5 Minority interest 3 ------- Net Earnings as adjusted $1,480 ------- Fixed Charges: Interest on long-term and short-term debt 96 Capitalized interest cost 3 Rental expense representative of an interest factor 32 ------- Total Fixed Charges 131 ------- Total adjusted earnings available for payment of fixed charges $1,611 ======= Ratio of earnings to fixed charges 12.3 ======= </Table> NOTE: For the purpose of calculating this ratio, (i) earnings have been calculated by adjusting net earnings for taxes on earnings; interest expense; capitalized interest cost, net of amortization; minority interest; and the portion of rentals representative of the interest factor, (ii) Abbott considers one-third of rental expense to be the amount representing return on capital, and (iii) fixed charges comprise total interest expense, including capitalized interest and such portion of rentals.