<PAGE>

                                 FIFTH AMENDMENT TO
                                  CREDIT AGREEMENT

     THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (this "Fifth Amendment") dated as
of May 1, 1998 is entered into by and among WELLPOINT HEALTH NETWORKS INC., a
Delaware corporation ("COMPANY"), each of the financial institutions that is a
signatory hereto (the "BANKS"), BANK OF AMERICA NATIONAL TRUST AND SAVINGS
ASSOCIATION, as administrative and bid agent for the Banks (in such capacity,
the "ADMINISTRATIVE AGENT"), NATIONSBANK OF TEXAS, N.A., as syndication agent
for the Banks (in such capacity, the "SYNDICATION AGENT"), and THE CHASE
MANHATTAN BANK, as documentation agent for the Banks (in such capacity the
"DOCUMENTATION AGENT"), and amends that certain Credit Agreement dated as of May
15, 1996 among the Company, the Banks, the Administrative Agent, Syndication
Agent and the Documentation Agent, as amended by a First Amendment to Credit
Agreement dated as of June 28, 1996, a Second Amendment to Credit Agreement
dated as of April 21, 1997. a Third Amendment to Credit Agreement dated as of
April 21, 1997 and a Fourth Amendment to Credit Agreement and Consent dated as
of July 21, 1997 as so amended, the "Agreement").

                                       RECITAL

     The Company has requested several amendments to the Agreement, and the
Banks and the Agents are willing to amend the Agreement on the terms and
conditions set forth herein.

     NOW, THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, the parties hereby agree as follows:

     1.   TERMS.  All terms used herein shall have the same meanings as in the
Agreement unless otherwise defined herein.  All references to the Agreement
shall mean the Agreement as hereby amended.

     2.   AMENDMENTS TO AGREEMENT.  The Agents and the Banks hereby agree that
the Agreement is amended as follows:

     2.1  The following new definitions are inserted in Section 1.01 of the
Agreement in proper alphabetical order as follows:

          "'Acquired EBITDA' means, with respect to any acquisition permitted
     under this Agreement, for any period, for the Company and its Subsidiaries
     (determined in accordance with GAAP), the sum of (a) consolidated pre-tax
     net income (exclusive of extraordinary gains and losses); PLUS, to the
     extent deducted in determining consolidated pre-tax net income, (b)
     Interest Expense, (c) amortization and (d) depreciation, all for such
     period, as each of the items specified above are reasonably allocable to
     the assets, capital stock, division or business group acquired in such
     acquisition."

          "'EBITDA' means, for the Company and its Subsidiaries (determined on a
     consolidated basis without duplication in accordance with GAAP), the sum of


                                         -1-
<PAGE>

     consolidated pre-tax net income (exclusive of extraordinary gains and
     losses) of the Company and its Subsidiaries for the four-quarter period
     ending on the date of determination plus (to the extent deducted in
     determining consolidated pre-tax net income) (a) Interest Expense for such
     period, (b) amortization for such period, (c) depreciation for such period,
     (d) up to $65,000,000 of restructuring charges or expenses incurred in
     connection with the Recapitalization and the Mirus Acquisition (determined
     on a pre-tax basis) and (e) up to $50,000,000 of non-cash restructuring
     charges or expenses (with any reserve constituting a cash charge) incurred
     in such period in connection with acquisitions permitted by the terms and
     conditions of this Agreement (determined on a pre-tax basis)."

          "'Pricing Funded Debt' means, as of any date of determination, for the
     Company and its Subsidiaries on a consolidated basis in accordance with
     GAAP, an amount equal to the sum of, without duplication, (a) all
     Indebtedness of such Persons plus (b) an amount equal to eight times the
     annual expense of such Persons in respect of any Operating Lease for the
     four-quarter period commencing on the date of determination plus (c) all
     Contingent Obligations of such Persons with respect to Funded Debt of
     others."

          "'Pricing Leverage Ratio' means the ratio of Pricing Funded Debt TO
     the sum of (a) EBITDAR plus (b) with respect to each acquisition permitted
     by this Agreement made during the four consecutive fiscal quarters
     immediately preceding any date of determination, the aggregate amount of
     Acquired EBITDAR for the period commencing on the first day of such four
     fiscal quarter period and ending on the date each such acquisition was
     made."

     2.2  The following definitions in Section 1.01 of the Agreement are amended
and restated in their entirety as follows:

          "'Fixed Charges' means, for any period, for the Company and its
     Subsidiaries on a consolidated basis in accordance with GAAP, an amount
     equal to the sum of, without duplication, (a) Interest Expense during the
     preceding four-quarter period ending on the date of determination PLUS
     (b) scheduled principal payments of Indebtedness for the succeeding
     four-quarter period commencing on the date of determination, other than
     payments in connection with the Mass Mutual Notes (unless renewable or
     extendible at the option of the obligor beyond such period)."

          "'Fixed Charge Coverage Ratio' means the ratio of (a) EBITDA to (b)
     Fixed Charges."

          "'Funded Debt' means, as of any date of determination, for the Company
     and its Subsidiaries on a consolidated basis in accordance with GAAP, an
     amount equal to the sum of, without duplication, (a) all Indebtedness of
     such Person plus (b) all Contingent Obligations of such Person with respect
     to Funded Debt of others."

          "'Leverage Ratio' means the ratio of Funded Debt TO the sum of (a)
     EBITDA plus (b) with respect to each acquisition permitted by this
     Agreement made during the four


                                         -2-
<PAGE>

     consecutive fiscal quarters immediately preceding any date of
     determination, the aggregate amount of Acquired EBITDA for the period
     commencing on the first day of such four fiscal quarter period and ending
     on the date each such acquisition was made."

     2.3  The definition of "Applicable Amount" in Section 1.01 of the Agreement
is amended by deleting "Leverage Ratio" and inserting "Pricing Leverage Ratio"
in lieu thereof.

     2.4  Section 7.01(b) of the Agreement (annual consolidating financial
statements) is amended and restated in its entirety as follows:

          "(b)  Intentionally left blank; and"

     2.5  Section 7.02(b) of the Agreement (investment portfolio reporting) is
amended and restated in its entirety as follows:

          "(b)  Intentionally left blank; and"

     2.6  Section 8.02(f) of the Agreement is amended and restated in its
entirety as follows:

          "(f)  additional Indebtedness of the Company incurred subsequent to
     the Closing Date; provided that at the time any such Indebtedness is
     incurred, no Default or Event of Default has occurred and is continuing or
     would result from the incurrence of such Indebtedness; and"

     2.7  Section 8.08 of the Agreement is amended and restated in its entirety
as follows:

          "8.08 LEVERAGE RATIO.  The Company shall not permit its Leverage
     Ratio to exceed 3.00 to 1 at any time."

     2.8  Section 8.12 of the Agreement is further amended by deleting "and" at
the end of subsection (j), deleting the period at the end of subsection (k) and
inserting "; and" in lieu thereof, and inserting a new subsection (l)
immediately after subsection (k) as follows:

          "(l)  Investments pursuant to guaranties or similar instruments of
     Subsidiary obligations required by HMO Regulators."

     2.9  Annex I to the Agreement is amended by deleting "Leverage Ratio"
wherever it appears and inserting "Pricing Leverage Ratio" in lieu thereof.

     2.10 Exhibit F to the Agreement is amended and restated in its entirety as
set forth in Exhibit F hereto.

     3.   REPRESENTATIONS AND WARRANTIES.  The Company represents and warrants
to the Banks and the Agents that, on and as of the date hereof, and after giving
effect to this Fifth Amendment:

     3.1  AUTHORIZATION.  The execution, delivery and performance of this Fifth


                                         -3-
<PAGE>

Amendment have been duly authorized by all necessary corporate action by the
Company and this Fifth Amendment has been duly executed and delivered by the
Company.

     3.2  BINDING OBLIGATION.  This Fifth Amendment is the legal, valid and
binding obligation of the Company enforceable against the Company, in accordance
with its terms, except as may be limited by bankruptcy, insolvency,
reorganization, moratorium or other similar laws relating to or limiting
creditors' rights generally or by equitable principles relating to
enforceability.

     3.3  NO LEGAL OBSTACLE TO AMENDMENT.  The execution, delivery and
performance of this Fifth Amendment will not (a) contravene the terms of the
Company's articles or certificate of incorporation, by-laws or other
organization document; (b) conflict with or result in any breach or
contravention of, or the creation of any Lien under, any document evidencing any
Contractual Obligation to which the Company is a party or any order, injunction,
writ or decree of any Governmental Authority to which the Company or its
Property is subject; or (c) violate any Governmental Rules where such violation
would reasonably be expected to have a Material Adverse Effect.

     3.4  INCORPORATION OF CERTAIN REPRESENTATIONS.  The representations and
warranties of the Company set forth in Article VI of the Agreement are true and
correct in all respects on and as of the date hereof as though made on and as of
the date hereof, except (a) to the extent such representations and warranties
expressly refer to an earlier date, in which case they shall be true and correct
as of such earlier date, and (b) that the Recapitalization itself shall not be
deemed to have a Material Adverse Effect for purposes of the representations and
warranties in Sections 6.11(b) and (c) of the Agreement.

     3.5  DEFAULT.  After giving effect to this Fifth Amendment, no Default or
Event of Default under the Agreement shall have occurred and be continuing.

     4.   CONDITIONS, EFFECTIVENESS.  The effectiveness of this Fifth Amendment
shall be subject to the compliance by the Company with its agreements herein
contained, and to the delivery of the following to the Administrative Agent in
form and substance satisfactory to the Administrative Agent:

     4.1  AUTHORIZED SIGNATORIES.  A certificate, signed by the Secretary or an
Assistant Secretary of the Company dated as of the date hereof, as to the
incumbency of the person or persons authorized to execute and deliver this Fifth
Amendment and any instrument or agreement required hereunder on behalf of the
Company.

     4.2  OTHER EVIDENCE.  Such other evidence with respect to the Company or
any other person as any Bank may reasonably request in connection with this
Fifth Amendment and the compliance with the conditions set forth herein.


                                         -4-
<PAGE>

5.   MISCELLANEOUS.

     5.1  EFFECTIVENESS OF AGREEMENT.  Except as hereby expressly amended, the
Agreement and each other Loan Document shall each remain in full force and
effect, and are hereby ratified and confirmed in all respects on and as of the
date hereof.

     5.2  NO WAIVER.  This Fifth Amendment is specific in time and in intent and
does not constitute, nor should it be construed as, a waiver of any other right,
power or privilege under the Loan Documents, or under any agreement, contract,
indenture, document or instrument mentioned in the Loan Documents; nor does it
preclude any exercise thereof or the exercise of any other right, power or
privilege, nor shall any future waiver of any right, power, privilege or default
hereunder, or under any agreement, contract, indenture, document or instrument
mentioned in the Loan Documents, constitute a waiver of any other default of the
same or of any other term or provision.

     5.3  COUNTERPARTS; ALL BANKS.  This Fifth Amendment may be executed in any
number of counterparts and all of such counterparts taken together shall be
deemed to constitute one and the same instrument.  This Fifth Amendment shall
become as of the date hereof upon the Company, the Majority Banks and the Agents
having signed a copy hereof, whether the same or counterparts, and the same
shall have been delivered to the Administrative Agent.

     5.4  JURISDICTION.  This Fifth Amendment shall be governed by and construed
under the laws of the State of California.

     IN WITNESS WHEREOF, the parties hereto have caused this Fifth Amendment to
be duly executed and delivered as of the date first written above.


                                  [Signatures omitted]




(Signatures continue)


                                         -5-
<PAGE>

                                                                       EXHIBIT F

                           FORM OF COMPLIANCE CERTIFICATE

                                                                          [DATE]

TO:  Bank of America National Trust
     and Savings Association, as Administrative Agent

Re:  Compliance Certificate

Ladies and Gentlemen:

     This Certificate is given in accordance with Section 7.02(a) of that
certain Credit Agreement dated as of May 15, 1996 (as from time to time amended,
extended, restated, modified or supplemented, the "Credit Agreement";
capitalized terms used herein shall have the meanings assigned to them in the
Credit Agreement), among WellPoint Health Networks Inc., the Banks party
thereto, Bank of America National Trust and Savings Association, as
Administrative Agent, NationsBank of Texas, N.A., as Syndication Agent, and
Chemical Bank, as Documentation Agent.  I the undersigned Responsible Officer
hereby certify that:

          (a)   I am the _______ ________ of the Company;

          (b)   The Company hereby selects the [PRICING LEVERAGE RATIO] [DEBT
     RATING] as the method for determining the Applicable Amount;

          (c)   The enclosed consolidated balance sheet, related consolidated
     statement of income, shareholders' equity and cash flows and the enclosed
     consolidating balance sheets and the related statements of income are
     complete and correct and fairly present, in accordance with GAAP, the
     financial position and the results of operations of the Company and the
     Subsidiaries for the periods indicated;

          (d)   We have reviewed the terms of the Credit Agreement and have
     made or caused to be made under our supervision, a review in reasonable
     detail of the transactions and financial condition of the Company during
     the accounting period covered by the enclosed financial statements;

          (e)   No event or condition exists which constitutes an Event of
     Default or Default as of the date of this certificate except as set forth
     below;

          (f)   The representations and warranties set forth in Article VI of
     the Credit Agreement are true, correct and complete in all material
     respects on and as of the date of this Certificate to the same extent as
     though made on and as of the date hereof; and


                                         F-1
<PAGE>

          (g)   The Company is in compliance with all of the terms and
     conditions of the Credit Agreement except as set forth below.

          (h)   The calculations in Attachment No. 1 to this Certificate are
     true, correct and complete.

          (i)   Pursuant to Section 7.03(f) of the Credit Agreement, the
     Company's Debt Ratings as of the date of this certificate are ____, in the
     case of Moody's, and ____, in the case of S&P.

          (j)   Pursuant to Section 8.01(i) of the Credit
     Agreement, the aggregate principal amount of Indebtedness
     secured by any and all purchase money security interests
     on any Property acquired or held by the Company or its
     Subsidiaries in the Ordinary Course of Business is                 $
                                                                         -------

          (k)   Pursuant to Section 8.01(j) of the Credit
     Agreement, the aggregate amount of Indebtedness secured
     by Liens in respect of Capital Leases on Property subject
     to such Capital Leases is                                   $
                                                                  ---------

          (l)   Pursuant to Section 8.02(d) of the Credit
     Agreement, the aggregate amount of Indebtedness of
     Subsidiaries of the Company (exclusive of Indebtedness
     permitted under Section 8.02(e) and Contingent Obligations
     of the Company and Subsidiaries of the Company in respect
     of such Indebtedness) is                                    $
                                                                  ---------

          (m)   Pursuant to Section 8.04(h) of the Credit Agreement, the
     net book value in the aggregate of all dispositions of Property during
     the current fiscal year is ______% of the Company's Total Assets as
     shown on its consolidated balance sheet for the previous fiscal year.

          (n)   Pursuant to Section 8.08 of the Credit
     Agreement, the Company's Leverage Ratio is                  $
                                                                  ---------

          (o)   Pursuant to Section 8.09 of the Credit Agreement,
     the Company's Fixed Charge Ratio is                         $
                                                                  ---------

          (p)   Pursuant to Section 8.10 of the Credit Agreement,
     the Company's Net Worth is                                  $
                                                                  ---------

          (q)   Pursuant to Section 8.12(j) of the Credit
     Agreement, the aggregate outstanding amount of Investments
     is                                                          $
                                                                  ---------


                                         F-2
<PAGE>

          Described below (or in a separate attachment hereto) are the
     exceptions, if any, to paragraphs (d) and (f), listing in detail, the
     nature of the conditions or event, the period during which it has existed
     and the action which the Company has taken, is taking or proposes to take
     with respect to each such condition or event:

          ----------------------------------------------------------

          ----------------------------------------------------------

          ----------------------------------------------------------

          ----------------------------------------------------------

          ----------------------------------------------------------

     The foregoing certifications are made and delivered this ____ day of
     _________, ____.


                              WELLPOINT HEALTH NETWORKS INC.,
                              A DELAWARE CORPORATION

                              By:
                                   ------------------------------
                              Name:
                                     ----------------------------
                              Title:
                                     ----------------------------


                                         F-3
<PAGE>

                                  ATTACHMENT NO. 1
                             TO COMPLIANCE CERTIFICATE

     This attachment is as of ______________ and, in the case of the Fixed
Charge Coverage Ratio, the Leverage Ratio and the Pricing Leverage Ratio set
forth below, pertains to the four-quarter period from ________ ________ to
_______ __________ (the "Period"; the last day of the Period is referred to
herein as the "Period End Date").  Financial covenant information is provided
for only those covenants which are required to be tested as of the Period End
Date.  All amounts are as of the Period End Date except as noted and are
calculated on a consolidated basis for the Company and its Subsidiaries..

     Capitalized terms used herein without definition shall have the meanings
set forth in the Credit Agreement dated as of May 15, 1996 (such agreement, as
it may be amended, supplemented, restated or otherwise modified from time to
time, the "Credit Agreement") by and among WellPoint Health Networks Inc., the
Banks party thereto, Bank of America National Trust and Savings Association, as
Administrative Agent, NationsBank of Texas, N.A., as Syndication Agent, and The
Chase Manhattan Bank, as Documentation Agent.  Section references are to the
sections of the Credit Agreement.


I.   DISPOSITIONS OF ASSETS (Section 8.04(h))

     A.   Total Assets for previous fiscal year:                 $
                                                                  ---------

     B.   10% of Line I.A:                                       $

                                                                  ---------
     C.   Net book value of dispositions of Property during

          current fiscal year:                                   $
                                                                  ---------

          MAXIMUM PERMITTED DISPOSITIONS:  LINE I.C NOT TO EXCEED LINE I.B

II.  LEVERAGE RATIO (Section 8.08)

     A.   Funded Debt:

          1.   Indebtedness:                                     $
                                                                  ---------

          2.   Contingent Obligations re Funded Debt of Others:  $
                                                                  ---------

          3.   Funded Debt (Lines: A1 + A2):                     $
                                                                  ---------


                                         F-1-1
<PAGE>

     B.   EBITDA

          1.   Consolidated pre-tax net income (exclusive of
                extraordinary gains and losses):                 $
                                                                  ---------
          2.   Interest Expense:

               a.   Related to Indebtedness:                     $
                                                                  ---------

               b.   Related to Swap Contracts:                   $
                                                                  ---------

               c.   Total Interest Expense (Lines B2.a+B2.b):    $
                                                                  ---------

          3.   Depreciation:                                     $
                                                                  ---------

          4.   Amortization:                                     $
                                                                  ---------

          5.   Up to $65,000,000 of restructuring charges or
               expenses in connection with the Recapitalization
               and the Mirus Acquisition (determined on a
               pre-tax basis):                                   $
                                                                  ---------

          6.   Up to $50,000,000 of non-cash restructuring
               charges or expenses (with any reserve
               constituting a cash charge) incurred in such
               period in connection with acquisitions permitted
               by the terms and conditions of this Agreement
               (determined on apre-tax basis):                   $
                                                                  ---------

          7.   EBITDA (Lines B1+B2.c+B3+B4+B5+B6):               $
                                                                  ---------
                                                                  ---------

     C.   Acquired EBITDA with respect to acquired Persons:

          1.   Consolidated pre-tax net income (exclusive of
               extraordinary gains and losses):                  $
                                                                  ---------

          2    Interest Expense:

               a.   Related to Indebtedness:                     $
                                                                  ---------

               b.   Related to Swap Contracts:                   $
                                                                  ---------

               c.   Total Interest Expense (Lines C2.a+C2.b):    $
                                                                  ---------

          3.   Depreciation:                                     $
                                                                  ---------

          4.   Amortization:                                     $
                                                                  ---------


                                         F-1-2
<PAGE>

          5.   Acquired EBITDA (Lines C1+C2.c+C3+C4):            $
                                                                  ---------
                                                                  ---------

     C.   Leverage Ratio (Line II.A3 DIVIDED BY [Line II.B7 +
           Line II.C5]):                                              to 1.00

     MAXIMUM PERMITTED LEVERAGE RATIO:                           3.00 TO 1.00

III. FIXED CHARGE COVERAGE RATIO (Section 8.09)

     A    Fixed Charges:

          1.   Interest Expense (Line II.B2.c):                  $
                                                                  ---------

          2.   Schedule principal payments on Indebtedness
               during succeeding four quarters:                  $
                                                                  ---------

          3.   Fixed Charges (Lines A1 + A2):                    $
                                                                  ---------

     B.   Fixed Charge Coverage: Ratio (Line II.B7 DIVIDED BY 
          Line III.A3) =                                         ____ to 1.00

     MINIMUM PERMITTED FIXED CHARGE COVERAGE:                    3:00 TO 1.00

IV.  MINIMUM NET WORTH (Section 8.10)

     A.   Net Worth

          1.   Capital Stock:                                    $
                                                                  ---------

          2.   Treasury Shares:                                  $
                                                                  ---------

          3.   Additional Paid In Capital:                       $
                                                                  ---------

          4.   Surplus and Retained Earnings:                    $
                                                                  ---------

          5.   Actual Net Worth (Lines A1 - A2 + A3 +A 4):       $
                                                                  ---------

     B.   Minimum Net Worth at Final Recapitalization Date
          (the greater of (i) 75% of the Company's Net Worth as
          of the Final Recapitalization Date and (ii)
          $500,000,000):                                         $
                                                                  ---------

     C.   Fifty Percent of Net Income from and after January 1,
          1996:                                                  $
                                                                  ---------

     D.   Total Required Minimum Net Worth (Lines IV.B + IV.C):  $
                                                                  ---------

     MINIMUM PERMITTED NET WORTH:  LINE IV.A.5 TO BE GREATER THAN LINE IV.D


                                         F-1-3
<PAGE>

III. PRICING LEVERAGE RATIO

     A.   Pricing Funded Debt

          1.   Indebtedness:                                     $
                                                                  ---------

          2.   Operating Lease expense, multiplied by eight:     $
                                                                  ---------

          3.   Contingent Obligations re Funded Debt of Others:  $
                                                                  ---------

          4.   Funded Debt (Lines: A1 +A 2+A3):                  $
                                                                  ---------

     B.   EBITDAR

          1.   Consolidated pre-tax net income (exclusive of
               extraordinary gains and losses) (Line II.B.1):         $
                                                                       ---------

          2    Interest Expense (Line II.B.2.c):                 $
                                                                  ---------

          3.   Depreciation (Line II.B.3):                       $
                                                                  ---------

          4.   Amortization (Line II.B.4):                       $
                                                                  ---------

          5.   Operating Lease expense:                          $
                                                                  ---------

          6.   Recapitalization and Mirus Acquisition
               restructuring charges or expenses (Line II.B.5):  $
                                                                  ---------

          7.   Other non-cash restructuring charges or expenses
               incurred in such period in connection with
               permitted acquisitions (Line II.B.6):             $
                                                                  ---------

          8.   EBITDAR (Lines B1+B2.c+B3+B4+B5+B6+B7):           $
                                                                  ---------
                                                                  ---------

          C.   Acquired EBITDAR with respect to acquired Persons:

          1.   Consolidated pre-tax net income (exclusive of
               extraordinary gains and losses) (Line II.C.1):         $
                                                                       ---------

          2    Interest Expense (Line II.C.2.c):                 $
                                                                  ---------

          3.   Depreciation (Line II.C.3):                       $
                                                                  ---------

          4.   Amortization(Line II.C.4):                        $
                                                                  ---------

          5.   Operating Lease expense:                          $
                                                                  ---------


                                         F-1-4
<PAGE>

          6.   Acquired EBITDAR (Lines C1+C2.c+C3+C4+C5):        $
                                                                  ---------
                                                                  ---------

     D.   Pricing Leverage Ratio (Line III.A4 DIVIDED BY
          [Line III.B.8 + Line III.C6]):                         _____ to 1.00



                                         F-1-5