<PAGE>   1

                                                                  EXHIBIT 10.115

SOUTHERN CALIFORNIA BANK
Member FDIC

                            CHANGE IN TERMS AGREEMENT

<TABLE>
<CAPTION>

==================================================================================================================
Principal      Loan Date     Maturity     Loan No.     Call        Collateral   Account      Officer     Initials
------------------------------------------------------------------------------------------------------------------
<S>            <C>           <C>          <C>          <C>         <C>          <C>          <C>         <C>
$1,500,000.00                05-01-2000   4000928      50            5015                      382
------------------------------------------------------------------------------------------------------------------

References in the shaded area are for Lender's use only and do not limit the Applicability of this document to
 any particular loan or item.
==================================================================================================================
</TABLE>

<TABLE>
<S>                                                             <C>
Borrower:  OPTIMUMCARE CORPORATION (TIN: 33-0218003)            Lender:  SOUTHERN CALIFORNIA BANK
           30011 IVY GLENN DRIVE #219                                    ORANGE COUNTY CORPORATE BANKING
           LAGUNA NIGUEL, CA 92677                                       P.O. BOX 588
                                                                         LA MIRADA, CA 90637
==================================================================================================================
</TABLE>

PRINCIPAL AMOUNT: $1,500,000.00                DATE OF AGREEMENT: APRIL 27, 1999

DESCRIPTION OF EXISTING INDEBTEDNESS.
- Promissory Note dated April 14, 1995 in the original amount of $500,000.00.
- Change in Terms Agreement dated May 6, 1996 extending the maturity date to
  July 1, 1996.
- Change in Terms Agreement dated August 1, 1996 increasing the principal amount
  to $750,000.00 and extending the maturity date to March 1, 1997.
- Change in Terms Agreement dated January 28, 1997, extending the maturity
  date to June 1, 1997.
- Change in Terms Agreement dated May 15, 1997, increasing the principal amount
  to $1,500,000.00 and extending the maturity date to May 1, 1998.
- Change in Terms Agreement dated May 1, 1998 extending the maturity date to
  June 15, 1998.
- And Change in Terms Agreement dated May 27, 1998, extending the maturity date
  to May 1, 1999.

DESCRIPTION OF COLLATERAL.
- All Inventory, Chattel Paper, Accounts, Equipment, General Intangibles and
  Fixtures.

DESCRIPTION OF CHANGE IN TERMS.
- Maturity date shall be extended from May 1, 1999 to May 1, 2000.
- Interest shall accrue at Wall Street Journal Prime Rate + 0.50% and computed
  on a 365/360 basis.

DESCRIPTION OF CHANGE IN LOAN AGREEMENT/COVENANTS.
- Advances to Shareholders/Officers not to exceed $392,000.00.

PROMISE TO PAY. OPTIMUMCARE CORPORATION ("BORROWER") PROMISES TO PAY TO SOUTHERN
CALIFORNIA BANK ("LENDER"), OR ORDER, IN LAWFUL MONEY OF THE UNITED STATES OF
AMERICA, THE PRINCIPAL AMOUNT OF ONE MILLION FIVE HUNDRED THOUSAND & 00/100
DOLLARS ($1,500,000.00) OR SO MUCH AS MAY BE OUTSTANDING, TOGETHER WITH INTEREST
ON THE UNPAID OUTSTANDING PRINCIPAL BALANCE OF EACH ADVANCE. INTEREST SHALL BE
CALCULATED FROM THE DATE OF EACH ADVANCE UNTIL REPAYMENT OF EACH ADVANCE.

PAYMENT. BORROWER WILL PAY THIS LOAN ON DEMAND, OR IF NO DEMAND IS MADE, IN ONE
PAYMENT OF ALL OUTSTANDING PRINCIPAL PLUS ALL ACCRUED UNPAID INTEREST ON MAY 1,
2000. IN ADDITION, BORROWER WILL PAY REGULAR MONTHLY PAYMENTS OF ACCRUED UNPAID
INTEREST BEGINNING JUNE 1, 1999, AND ALL SUBSEQUENT INTEREST PAYMENTS ARE DUE ON
THE SAME DAY OF EACH MONTH AFTER THAT. The annual interest rate for this
Agreement is computed on a 365/360 basis; that is, by applying the ratio of the
annual interest rate over a year of 360 days, multiplied by the outstanding
principal balance, multiplied by the actual number of days the principal balance
is outstanding. Borrower will pay Lender at Lender's address shown above or at
such other place as Lender may designate in writing. Unless otherwise agreed or
required by applicable law, payments will be applied first to accrued unpaid
interest, then to principal, and any remaining amount of any unpaid collection
costs and late charges.

VARIABLE INTEREST RATE. The interest rate on this Agreement is subject to change
from time to time based on changes in an independent index which is the WALL
STREET JOURNAL PRIME RATE (the "Index"). The Index is not necessarily the lowest
rate charged by Lender on its loans. If the Index becomes unavailable during the
term of this loan, Lender may designate a substitute index after notice to
Borrower. Lender will tell Borrower the current Index rate upon Borrower's
request. Borrower understands that Lender may make loans based on other rates as
well. The interest rate change will not occur more often than each DAY. THE
INDEX CURRENTLY IS 7.750%. THE INTEREST RATE TO BE APPLIED TO THE UNPAID
PRINCIPAL BALANCE OF THIS AGREEMENT WILL BE AT A RATE OF 0.500 PERCENTAGE POINTS
OVER THE INDEX, RESULTING IN AN INITIAL RATE OF 8.250%. NOTICE: Under no
circumstances will the interest rate on this Agreement be more than the maximum
rate allowed by applicable law.


                                       1

<PAGE>   2

PREPAYMENT; MINIMUM INTEREST CHARGE. Borrower agrees that all loan fees and
other prepaid finance charges are earned fully as of the date of the loan and
will not be subject to refund upon early payment (whether voluntary or as a
result of default), except as otherwise required by law. In any event, even upon
full prepayment of this Agreement, Borrower understands that Lender is entitled
to a MINIMUM INTEREST CHARGE OF $250.00. Other than Borrower's obligation to pay
any minimum interest charge, Borrower may pay without penalty all or a portion
of the amount owed earlier than it is due. Early payments will not, unless
agreed to by Lender in writing, relieve Borrower of Borrower's obligation to
continue to make payments of accrued unpaid interest. Rather, they will reduce
the principal balance due.

LATE CHARGE. If a payment is 10 DAYS OR MORE LATE, Borrower will be charged
5.000% OF THE REGULARLY SCHEDULED PAYMENT OR $5.00, WHICHEVER IS GREATER.

DEFAULT. Borrower will be in default if any of the following happens: (a)
Borrower fails to make any payment when due. (b) Borrower breaks any promise
Borrower has made to Lender, or Borrower fails to comply with or to perform when
due any other term, obligation, covenant, or condition contained in this
Agreement or any agreement related to this Agreement, or in any other agreement
or loan Borrower has with Lender. (c) Borrower defaults under any loan,
extension of credit, security agreement, purchase or sales agreement, or any
other agreement, in favor of any other creditor or person that may materially
affect any of Borrower's property or Borrower's ability to repay this Note or
perform Borrower's obligations under this Note or any of the Related Documents.
(d) Any representation or statement made or furnished to Lender by Borrower or
on Borrower's behalf is false or misleading in any material respect either now
or at the time made or furnished. (e) Borrower becomes insolvent, a receiver is
appointed for any part of Borrower's property, Borrower makes an assignment for
the benefit of creditors, or any proceeding is commenced either by Borrower or
against Borrower under any bankruptcy or insolvency laws. (f) Any creditor tries
to take any of Borrower's property on or in which Lender has a lien or security
interest. This includes a garnishment of any of Borrower's accounts with Lender.
(g) Any guarantor dies or any of the other events described in this default
section occurs with respect to any guarantor of this Agreement. (h) A material
adverse change occurs in Borrower's financial condition, or Lender believes the
prospect of payment or performance of the Indebtedness is impaired. (i) Lender
in good faith deems itself insecure.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Agreement and all accrued unpaid interest immediately due,
without notice, and then Borrower will pay that amount. Upon Borrower's failure
to pay all amounts declared due pursuant to this section, including failure to
pay upon final maturity, Lender, at its option, may also , if permitted under
applicable law, increase the variable interest rate on this Agreement to 5.500
percentage points over the Index. Lender may hire or pay someone else to help
collect this Agreement if Borrower does not pay. Borrower also will pay Lender
that amount. This includes, subject to any limits under applicable law, Lender's
attorneys' fees and Lender's legal expenses whether or not there is a lawsuit,
including attorneys' fees and legal expenses for bankruptcy proceedings
(including efforts to modify or vacate any automatic stay or injunction),
appeals, and any anticipated post-judgment collection services. Borrower also
will pay any court costs, in addition to all other sums provided by law. THIS
AGREEMENT HAS BEEN DELIVERED TO LENDER AND ACCEPTED BY LENDER IN THE STATE OF
CALIFORNIA. IF THERE IS A LAWSUIT, BORROWER AGREES UPON LENDER'S REQUEST TO
SUBMIT TO THE JURISDICTION OF THE COURTS OF ORANGE COUNTY, THE STATE OF
CALIFORNIA. LENDER AND BORROWER HEREBY WAIVE THE RIGHT TO ANY JURY TRIAL IN ANY
ACTION, PROCEEDING, OR COUNTERCLAIM BROUGHT BY EITHER LENDER OR BORROWER AGAINST
THE OTHER. SUBJECT TO THE PROVISIONS ON ARBITRATION, THIS AGREEMENT SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
CALIFORNIA.

DISHONORED ITEM FEE. Borrower will pay a fee to Lender of $16.00 if Borrower
makes a payment on Borrower's loan and the check or preauthorized charge with
which Borrower pays is later dishonored.

RIGHT OF SET OFF. Borrower grants to Lender a contractual security interest in,
and hereby assigns, conveys, delivers, pledges, and transfers to Lender all
Borrower's right, title and interest in and to, Borrower's accounts with Lender
(whether checking, savings, or some other account), including without limitation
all accounts held jointly with someone else and all accounts Borrower may open
in the future, excluding however all IRA and Keogh accounts, and all trust
accounts for which the grant of a security interest would be prohibited by law.
Borrower authorizes Lender, to the extent permitted by applicable law, to charge
or set off all sums owing on this Agreement against any and all such accounts.


                                       2

<PAGE>   3

LINE OF CREDIT. This Agreement evidences a revolving line of credit. Advances
under this Agreement may be requested only in writing by Borrower or by an
authorized person. All communications, instructions, or directions by telephone
or otherwise to Lender are to be directed to Lender's office shown above. The
following party or parties are authorized to request advances under the line of
credit until Lender receives from Borrower at Lender's address shown above
written notice of revocation of their authority: EDWARD A. JOHNSON, PRESIDENT.
Borrower agrees to be liable for all sums either: (a) advanced in accordance
with the instructions of an authorized person or (b) credited to any of
Borrower's accounts with Lender. The unpaid principal balance owing on this
Agreement at any time may be evidenced by endorsements on this Agreement or by
Lender's internal records, including daily computer print-outs. Lender will have
no obligation to advance funds under this Agreement if: (a) Borrower or any
guarantor is in default under the terms of this Agreement or any agreement that
Borrower or any guarantor has with Lender, including any agreement made in
connection with the signing of this Agreement; (b) Borrower or any guarantor
ceases doing business or is insolvent; (c) any guarantor seeks, claims or
otherwise attempts to limit, modify or revoke such guarantor's guarantee of this
Agreement or any other loan with Lender; or (d) Borrower has applied funds
provided pursuant to this Agreement for purposes other than those authorized by
Lender; or (e) Lender in good faith deems itself insecure under this Agreement
or any other agreement between Lender and Borrower.

ARBITRATION. Lender and Borrower agree that all disputes, claims and
controversies between them, whether individual, joint, or class in nature,
arising from this Agreement or otherwise, including without limitation contract
and tort disputes, shall be arbitrated pursuant to the Rules of the American
Arbitration Association, upon request of either party. No act to take or dispose
of any collateral securing this Agreement shall constitute a waiver of this
arbitration agreement or be prohibited by this arbitration agreement. This
includes, without limitation, obtaining injunctive relief or a temporary
restraining order; invoking a power of sale under any deed of trust or mortgage;
obtaining a writ of attachment or imposition of a receiver; or exercising any
rights relating to personal property, including taking or disposing of such
property with or without judicial process pursuant to Article 9 of the Uniform
Commercial Code. Any disputes, claims, or controversies concerning the
lawfulness or reasonableness of any act, or exercise of any right, concerning
any collateral securing this Agreement, including any claim to rescind, reform,
or otherwise modify any agreement relating to the collateral securing this
Agreement, shall also be arbitrated, provided however that no arbitrator shall
have the right or the power to enjoin or restrain any act of any party. Lender
and Borrower agree that in the event of an action for judicial foreclosure
pursuant to California Code of Civil Procedure Section 726, or any similar
provision in any other state, the commencement of such an action will not
constitute a waiver of the right to arbitrate and the court shall refer to
arbitration as much of such action, including counterclaims, as lawfully may be
referred to arbitration. Judgment upon any award rendered by any arbitrator may
be entered in any court having jurisdiction. Nothing in this Agreement shall
preclude any party from seeking equitable relief from a court of competent
jurisdiction. The statute of limitations, estoppel, waiver, laches, and similar
doctrines which would otherwise be applicable in an action brought by a party
shall be applicable in any arbitration proceeding, and the commencement of an
arbitration proceeding shall be deemed the commencement of an action for these
purposes. The Federal Arbitration Act shall apply to the construction,
interpretation, and enforcement of this arbitration provision.

CONTINUING VALIDITY. Except as expressly changed by this Agreement, the terms of
the original obligation or obligations, including all agreements evidenced or
securing the obligation(s), remain unchanged and in full force and effect.
Consent by Lender to this Agreement does not waive Lender's right to strict
performance of the obligation(s) as changed, nor obligate Lender to make any
future change in terms. Nothing in this Agreement will constitute a satisfaction
of the obligation(s). It is the intention of Lender to retain as liable parties
all makers and endorsers of the original obligation(s), including accommodation
parties, unless a party is expressly released by Lender in writing. Any maker or
endorser, including accommodation makers, will not be released by virtue of this
Agreement. If any person who signed the original obligation does not sign this
Agreement below, then all persons signing below acknowledge that this Agreement
is given conditionally, based on the representation to Lender that the
non-signing party consents to the changes and provisions of this Agreement or
otherwise will not be released by it. This waiver applies not only to any
initial extension, modification or release, but also to all such subsequent
actions.


                                       3

<PAGE>   4

MISCELLANEOUS PROVISIONS. This Agreement is payable on demand. The inclusion of
specific default provisions or rights of Lender shall not preclude Lender's
right to declare payment of this Agreement on its demand. Lender may delay or
forgo enforcing any of its rights or remedies under this Agreement without
losing them. Borrower and any other person who signs, guarantees or endorses
this Agreement, to the extent allowed by law, waive any applicable statute of
limitations, presentment, demand for payment, protest and notice of dishonor.
Upon any change in the terms of this Agreement, and unless otherwise expressly
stated in writing, no party who signs

this Agreement, whether as maker, guarantor, accommodation maker or endorser,
shall be released from liability. All such parties agree that Lender may renew
or extend (repeatedly and for any length of time) this loan, or release any
party or guarantor or collateral; or impair, fail to realize upon or perfect
Lender's security interest in the collateral; and take any other action deemed
necessary by Lender without the consent of or notice to anyone. All such parties
also agree that Lender may modify this loan without the consent of or notice to
anyone other than the party with whom the modification is made.

PRIOR TO SIGNING THIS AGREEMENT, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS
OF THIS AGREEMENT, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. BORROWER
AGREES TO THE TERMS OF THE AGREEMENT AND ACKNOWLEDGES RECEIPT OF A COMPLETED
COPY OF THE AGREEMENT.

BORROWER:

OPTIMUMCARE CORPORATION

BY: EDWARD A JOHNSON
    ---------------------------
    EDWARD A JOHNSON, PRESIDENT

                                       4
<PAGE>   5


SOUTHERN CALIFORNIA BANK
Member FDIC

                     DISBURSEMENT REQUEST AND AUTHORIZATION

<TABLE>
<CAPTION>
===================================================================================================================
Principal         Loan Date   Maturity    Loan No.     Call         Collateral  Account      Officer      Initials
-------------------------------------------------------------------------------------------------------------------
<S>               <C>         <C>         <C>          <C>          <C>         <C>          <C>          <C>
$1,500,000.00                 05-01-2000  4000928                     50         5015                     382
-------------------------------------------------------------------------------------------------------------------

References in the shaded area are for Lender's use only and do not limit the
applicability of this document to any particular loan or item.
===================================================================================================================
</TABLE>

<TABLE>
<S>                                                      <C>
Borrower:  OPTIMUMCARE CORPORATION (TIN: 33-0218003)     Lender:  SOUTHERN CALIFORNIA BANK
           30011 IVY GLENN DRIVE #219                             ORANGE COUNTY CORPORATE BANKING
           LAGUNA NIGUEL, CA 92677                                P.O. BOX 588
                                                                  LA MIRADA, CA 90637
==================================================================================================
</TABLE>

LOAN TYPE. This is a Variable Rate (0.500% over WALL STREET JOURNAL PRIME RATE,
making an initial rate of 8.250%), Revolving Line of Credit Loan to a
Corporation for $1,500,000.00 due on May 1, 2000.

PRIMARY PURPOSE OF LOAN.  The primary purpose of this loan is for:

                 Personal, Family or Household Purposes or Personal Investment
           ---

            X    Business (Including Real Estate Investment).
           ---

SPECIFIC PURPOSE. The specific purpose of this loan is: Short term working
capital needs.

DISBURSEMENT INSTRUCTIONS. Borrower understands that no loan proceeds will be
disbursed until all of Lender's conditions for making the loan have been
satisfied. Please disburse the loan proceeds of $1,500,000.00 as follows:

         Undisbursed Funds:                     $1,500,000.00

         Amount paid on Borrower's account:             $0.00
                                                -------------
         Note Principal:                        $1,500,000.00
                                                =============

CHARGES PAID IN CASH. Borrower has paid or will pay in cash as agreed the
following charges:

         Prepaid Finance Charges Paid in Cash:                       $3,750.00
                  $3,750.00 Loan Fee

                                                                     ---------
         Total Charges Paid in Cash:                                 $3,750.00
                                                                     =========

FINANCIAL CONDITION. BY SIGNING THIS AUTHORIZATION, BORROWER REPRESENTS AND
WARRANTS TO LENDER THAT THE INFORMATION PROVIDED ABOVE IS TRUE AND CORRECT AND
THAT THERE HAS BEEN NO MATERIAL ADVERSE CHANGE IN BORROWER'S FINANCIAL CONDITION
AS DISCLOSED IN BORROWER'S MOST RECENT FINANCIAL STATEMENT TO LENDER. THIS
AUTHORIZATION IS DATED APRIL 27, 1999.

BORROWER:

OPTIMUMCARE CORPORATION


By: EDWARD A. JOHNSON
    ----------------------------
    EDWARD A. JOHNSON, PRESIDENT


                                       5