EXHIBIT 12

McKESSON CORPORATION
COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

	Years Ended March 31,
(Dollars in millions)	2010			2009			2008			2007			2006
Earnings:
Income from continuing operations before income taxes	$	1,864		$	1,064		$	1,457		$	1,297		$	1,171
Adjustment to exclude equity in net income of and dividends from equity investees		(2	)		(1	)		(17	)		(17	)		(15	)
Fixed charges		240			195			198			141			133
Amortization of capitalized interest		4			4			4			3			2
Less: Capitalized interest		—			(1	)		(3	)		(3	)		(4	)
Earnings as adjusted	$	2,106		$	1,261		$	1,639		$	1,421		$	1,287
Fixed charges:
Interest expense (a) (c)	$	187		$	144		$	142		$	99		$	94
Capitalized interest		—			1			3			3			4
Portion of rental expense representative of the interest factor (b)		53			50			53			39			35
Total fixed charges	$	240		$	195		$	198		$	141		$	133
Ratio:
Ratio of earnings to fixed charges		8.8			6.5			8.3			10.1			9.7

(a)	Interest expense includes amortization of debt discounts and deferred loan costs.
(b)	One-third of net rent expense is the portion of rental expense deemed representative of the interest factor.
(c)	Interest accrued on the liability recorded for uncertain tax positions is excluded from Interest expense.