Pursuant to Rule 424(b)(3)

File No. 333-102909

SUPPLEMENT TO PROSPECTUS

DATED FEBRUARY 12, 2003

PACIFICARE HEALTH SYSTEMS, INC.

$135,000,000 3% CONVERTIBLE SUBORDINATED DEBENTURES

DUE 2032 AND 3,214,283 SHARES OF COMMON STOCK ISSUABLE

UPON CONVERSION OF THE DEBENTURES

      The Prospectus, dated February 12, 2003, is hereby supplemented as follows to restate, in its entirety, the “Selling Securityholders” section on pages 47-49 of the Prospectus.

      The date of this Prospectus Supplement is February 28, 2003.

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SELLING SECURITYHOLDERS

      We originally issued the debentures to the initial purchasers, Morgan Stanley & Co. Incorporated and Goldman Sachs & Co., in a private placement in November 2002 and in connection with the exercise in part by the initial purchasers of their option to purchase additional debentures in December 2002. The debentures were immediately resold by the initial purchasers in transactions exempt from registration under Rule 144A under the Securities Act. Selling securityholders, which term includes their transferees, pledgees, donees or their successors, may from time to time offer and sell the debentures and the common stock into which the debentures are convertible pursuant to this prospectus or any applicable prospectus supplement.

      The following table sets forth certain information concerning the principal amount of debentures beneficially owned and the number of shares of common stock issuable upon conversion of those debentures that may be offered from time to time under this prospectus by the selling securityholders named in the table. We prepared this table based on the information supplied to us by the selling securityholders named in the table and we have not sought to verify such information. This table only reflects information regarding selling securityholders who have provided us with such information. We expect that we will update this table as we receive more information from holders of the debentures who have not yet provided us with their information. We will supplement or amend this prospectus to include additional selling securityholders upon request and upon provision of all required information to us. Information concerning the selling securityholders may change from time to time and any changed information will be set forth in supplements to this prospectus if and when necessary.

      The number of shares of common stock issuable upon conversion of the debentures shown in the table below assumes conversion of the full amount of debentures held by each selling securityholder at an initial conversion rate of 23.8095 shares per $1,000 principal amount of debentures. This conversion price is subject to adjustment in certain events. Accordingly, the number of conversion shares may increase or decrease from time to time. The percentages of common stock beneficially owned and being offered are based on the number of shares of our common stock that were outstanding as of January 28, 2003. Because the selling securityholders may offer all or some portion of the debentures or the shares of common stock issuable upon conversion of the debentures pursuant to this prospectus, we have assumed for purposes of the table below that the selling securityholders will sell all of the debentures and all of the shares of common stock offered by this prospectus pursuant to this prospectus. In addition, the selling securityholders identified below may have sold, transferred or otherwise disposed of all or a portion of their debentures in transactions exempt from the registration requirements of the Securities Act since the date on which they provided the information to us regarding their holdings. As of January 28, 2003, we had $135,000,000 in principal amount of the debentures and 36,130,000 shares of common stock outstanding.

      Based upon information provided by the selling securityholders, none of the selling securityholders nor any of their affiliates, officers, directors or principal equity holders has held any position or office or has had any material relationship with us within the past three years.

	Principal					Shares of				Common Stock Owned
	Amount of					Common		Conversion		Upon Completion of
	Debentures					Stock		Shares of		the Offering
	Beneficially		Percentage of			Beneficially		Common
	Owned and		Debentures			Owned Before		Stock		Number of
Name	Offered		Outstanding			the Offering(1)		Offered		Shares		Percentage
Grace Brothers Management, LLC	$	2,750,000		2	%		—		65,476		—		*
Highbridge International LLC	$	1,250,000		*			—		29,761		—		*
Cobra Fund U.S.A., LP	$	222,000		*			—		5,285		—		*
Cobra Master Fund Ltd.	$	1,778,000		1	%		—		42,333		—		*
AIG DKR SoundShore Opportunity Holding Fund Ltd.	$	1,000,000		*			—		23,809		—		*
KBC Financial Products USA Inc.	$	450,000		*			—		10,714		—		*
McMahan Securities Co. L.P.	$	4,700,000		3	%		—		111,904		—		*

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	Principal					Shares of				Common Stock Owned
	Amount of					Common		Conversion		Upon Completion of
	Debentures					Stock		Shares of		the Offering
	Beneficially		Percentage of			Beneficially		Common
	Owned and		Debentures			Owned Before		Stock		Number of
Name	Offered		Outstanding			the Offering(1)		Offered		Shares		Percentage
Calamos® Market Neutral Fund-Calamos® Investment Trust	$	12,450,000		9	%		—		296,428		—		*
Drake Offshore Master Fund, Ltd.	$	4,000,000		3	%		—		95,238		—		*
Victus Capital, LP	$	1,000,000		*			—		23,809		—		*
MFS Total Return Fund	$	2,000,000		1	%		—		47,619		—		*
Man Convertible Bond Master Fund, Ltd.	$	3,997,000		3	%		—		95,166		—		*
Consulting Group Capital Markets Funds	$	1,200,000		*			—		28,571		—		*
BNP Paribas Equity Strategies SNC	$	4,461,000		3	%		26,801		106,214		26,801		*
CooperNeff Convertible Strategies (Cayman) Master Fund, LP	$	2,761,000		2	%		—		65,738		—		*
UFJ Investments Asia Limited	$	250,000		*			—		5,952		—		*
Laurel Ridge Capital LP	$	100,000		*			—		2,380		—		*
St. Thomas Trading, Ltd.	$	7,253,000		5	%		—		172,690		—		*
SG Cowen Securities Corporation	$	1,000,000		*			—		23,809		—		*
S.A.C. Capital Associates, LLC	$	2,000,000		1	%		—		47,619		—		*
D.E. Shaw Valence Portfolios, L.P.	$	2,400,000		2	%		—		57,142		—		*
D.E. Shaw Investment Group, L.P.	$	600,000		*			—		14,285		—		*
OCM Convertible Trust	$	240,000		*			—		5,714		—		*
Delta Air Lines Master Trust (c/o Oaktree Capital Management, LLC)	$	80,000		*			—		1,904		—		*
State Employees’ Retirement Fund of the State of Delaware	$	105,000		*			—		2,499		—		*
Partner Reinsurance Company Ltd.	$	80,000		*			—		1,904		—		*
Chrysler Corporation Master Retirement Trust	$	355,000		*			—		8,452		—		*
Motion Picture Industry Health Plan — Active Member Fund	$	25,000		*			—		595		—		*
Motion Picture Industry Health Plan — Retiree Member Fund	$	15,000		*			—		357		—		*
Vanguard Convertible Securities Fund, Inc.	$	385,000		*			—		9,166		—		*
Delta Pilots D & S Trust (c/o Oaktree Capital Management, LLC)	$	50,000		*			—		1,190		—		*
Microsoft Corporation	$	135,000		*			—		3,214		—		*
Qwest Occupational Health Trust	$	30,000		*			—		714		—		*
Canyon Value Realization MAC 18, Ltd. (RMF)	$	500,000		*			—		11,904		—		*
Canyon Value Realization Fund, L.P.	$	2,000,000		1	%		—		47,619		—		*
Canyon Value Realization Fund (Cayman), Ltd.	$	4,500,000		3	%		—		107,142		—		*
Canyon Capital Arbitrage Master Fund, Ltd.	$	3,000,000		2	%		—		71,428		—		*
JP Morgan Securities Inc.	$	7,000,000		5	%		—		166,666		—		*
Amaranth LLC	$	7,225,000		5	%		5,100		172,023		5,100		*

S-3

	Principal					Shares of				Common Stock Owned
	Amount of					Common		Conversion		Upon Completion of
	Debentures					Stock		Shares of		the Offering
	Beneficially		Percentage of			Beneficially		Common
	Owned and		Debentures			Owned Before		Stock		Number of
Name	Offered		Outstanding			the Offering(1)		Offered		Shares		Percentage
Argent Classic Convertible Arbitrage Fund L.P.	$	2,000,000		1	%		—		47,619		—		*
Argent Classic Convertible Arbitrage Fund (Bermuda) Ltd.	$	7,500,000		6	%		—		178,571		—		*
LLT Limited	$	78,000		*			—		1,857		—		*
Btop Equity Opportunity	$	80,000		*			—		1,904		—		*
Btcs — Convertible Arbitrage	$	20,000		*			—		476		—		*
Forest Multi-Strategy Master Fund SPC, on behalf of Series F, Multi-Strategy Segregated Portfolio	$	59,000		*			—		1,404		—		*
Forest Fulcrum Fund LLP	$	167,000		*			—		3,976		—		*
B.G.I. Global Investors c/o Forest Investment Management LLC	$	62,000		*			—		1,476		—		*
Zurich Master Hedge Fund c/o Forest Investment Management LLC	$	100,000		*			—		2,389		—		*
Forest Global Convertible Fund Series A-5	$	822,000		*			—		19,571		—		*
Lyxor Master Fund c/o Forest Investment Management LLC	$	217,000		*			—		5,166		—		*
Reylay 11 Holdings c/o Forest Investment Management LLC	$	31,000		*			—		738		—		*
RBC Alternative Assets LP c/o Forest Investment Management LLC	$	47,000		*			—		1,119		—		*
Sphinx Convertible Arbitrage c/o Forest Investment Management LLC	$	17,000		*			—		404		—		*
Grace Convertible Arbitrage Fund, Ltd	$	3,600,000		1	%		—		85,714		—		*
Sunrise Partners Limited Partnership	$	13,525,000		10	%		—		322,023		—		*
Jeffries & Co. Inc.	$	1,100,000		1	%		—		26,190		—		*
Sturgeon Limited	$	578,000		*			—		13,761		—		*
Morgan Stanley Capital Service Inc.	$	3,213,000		2	%		—		76,499		—		*
Deutsche Bank Securities Inc.	$	13,600,000		10	%		—		323,809		—		*
Quest Global Master Fund Ltd.	$	600,000		*			—		14,285		—		*
Topanga XI	$	2,787,000		2	%		—		66,375		—		*

(1)	Figures in this column do not include the shares of common stock issuable upon conversion of the debentures listed in the column to the right.
*	Less than one percent

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