Filing under Rule 424(b)(3)
Registration File No. 333-77569

 
Pricing Supplement No. 4
Dated January 30, 2001
(to Prospectus dated August 3,
2000 and Prospectus Supplement
dated September 7, 2000)

Merck & Co., Inc.
Medium-Term Notes, Series D
Floating Rate Notes

Principal Amount	$26,000,000
Trade Date:	January 30, 2001
Settlement Date (Original Issue Date):	February 6, 2001
Stated Maturity:	February 6, 2041
Interest Rate Basis:	3-month LIBOR
Spread:	Minus 45 basis points
Initial Interest Rate:	3-month LIBOR, determined as if the original issue date were an interest reset date, minus the spread
Interest Reset Dates:	The 6th day of February, May, August and November of each year
Interest Payment Dates:	The 6th day of February, May, August and November of each year, commencing May 6, 2001
Issue Price:	100.00% of the principal amount
Underwriter's Discount:	1.00% of the principal amount
Net Proceeds to Merck:	99.00% of the principal amount
Calculation Agent:	U.S. Bank Trust National Association
CUSIP:	58933N AQ 2

Optional
Repayment Dates:  
The notes will be repaid at the option of the holder on the optional repayment dates (subject to prior notice) and at the repayment prices as shown below:

Optional Repayment Dates	Repayment Price
February 6, 2011	99.00%
February 6, 2014	99.25%
February 6, 2017	99.50%
February 6, 2020	99.75%
February 6, 2023 and February 6 of each third year thereafter until maturity	100.00%

Underwriter: Morgan Stanley & Co. Incorporated

MORGAN STANLEY DEAN WITTER