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                                                                   EXHIBIT 10.20



                                 LOAN AGREEMENT

                               September 25, 1998



MedicalControl, Inc.
8625 King George
Suite 300
Dallas, Texas 75235

Ladies and Gentlemen:

         This Loan Agreement (the "LOAN AGREEMENT") will serve to set forth the
terms of the financing transactions by and between MEDICAL CONTROL, INC., a
Delaware corporation ("BORROWER"), and BANK ONE, TEXAS, NATIONAL ASSOCIATION
("BANK"):

         1. CREDIT FACILITIES. Subject to the terms and conditions set forth in
this Loan Agreement and the other agreements, instruments and documents
evidencing, securing, governing, guaranteeing and/or pertaining to the Loans, as
hereinafter defined (collectively, together with the Loan Agreement, referred to
hereinafter as the "LOAN DOCUMENTS"), Bank hereby agrees to lend to Borrower (a)
the amount of $1,600,000 (the "TERM LOAN") in a single advance on the date
hereof, and (b) (the "LINE OF CREDIT"), on a revolving basis from time to time
during the period commencing on the date hereof and continuing through the
maturity date of the promissory note evidencing this credit facility from time
to time, such amounts as Borrower may request hereunder; provided, however, the
total principal amount outstanding at any time under the Line of Credit shall
not exceed $500,000 (the Line of Credit and the Term Loan are collectively
referred to herein as the "CREDIT FACILITIES"). Subject to the terms and
conditions hereof, Borrower may borrow, repay and reborrow hereunder. The sums
advanced under the Loans shall be used for acquisition of a subsidiary and used
for general working capital purposes.

All advances under the Credit Facilities shall be collectively called the
"LOANS". Bank reserves the right to require Borrower to give Bank not less than
one (1) business day prior notice of each requested advance under the Line of
Credit, specifying (i) the aggregate amount of such requested advance, (ii) the
requested date of such advance, and (iii) the purpose for such advance, with
such advances to be requested in a form satisfactory to Bank. Borrower shall pay
to Bank upon the execution of this Agreement a facility fee in the amount of
$16,000. In addition, Borrower shall pay to Bank during the term of the Line of
Credit an unused fee equal to .25% per annum quarterly in arrears, of an amount
equal to $500,000 less the average outstanding balance under the Line of Credit.








LOAN AGREEMENT - Page 1

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         2. PROMISSORY NOTES. The Line of Credit and the Term Loan shall be
evidenced by one or more promissory notes (such promissory notes, together with
any renewals, extensions and increases thereof, the "Note") duly executed by
Borrower and payable to the order of Bank, in form and substance acceptable to
Bank. Interest on the Note shall accrue at the rate set forth therein. The
principal of and interest on the Note shall be due and payable in accordance
with the terms and conditions set forth in the Note and in this Loan Agreement.

         3. COLLATERAL. As collateral and security for the indebtedness
evidenced by the Note and any and all other indebtedness or obligations from
time to time owing by Borrower to Bank, Borrower shall grant, and hereby grants,
to Bank, its successors and assigns, a first and prior lien and security
interest in and to the property described hereinbelow, together with any and all
PRODUCTS AND PROCEEDS thereof (the "COLLATERAL"):

                  (a) All present and future accounts, chattel paper, documents,
         instruments, deposit accounts and general intangibles (including any
         right to payment for goods sold or services rendered arising out of the
         sale or delivery of personal property or work done or labor performed
         by Borrower), now or hereafter owned, held, or acquired by Borrower,
         together with any and all books of account, customer lists and other
         records relating in any way to the foregoing.

                  (b) All present and hereafter acquired inventory (including
         without limitation, all raw materials, work in process and finished
         goods) held, possessed, owned, held on consignment, or held for sale,
         lease, return or to be furnished under contracts of service, in whole
         or in part, by Borrower wherever located.

                  (c) All equipment and fixtures of whatsoever kind and
         character now or hereafter possessed, held, acquired, leased or owned
         by Borrower and used or usable in Borrower's business, together with
         all replacements, accessories, additions, substitutions and accessions
         to all of the foregoing.

                  (d) Any and all other assets, whether tangible or intangible,
         of Borrower.

The term "COLLATERAL" shall also include all records and data relating to any of
the foregoing (including, without limitation, any computer software on which
such records and data may be located). Borrower agrees to execute such security
agreements, assignments, deeds of trust and other agreements and documents as
Bank shall deem appropriate and otherwise require from time to time to more
fully create and perfect Bank's lien and security interests in the Collateral.



LOAN AGREEMENT - Page 2

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         5. GUARANTORS. As a condition precedent to the Bank's obligation to
make the Loans to Borrower, Borrower agrees to cause MedicalControl Network
Solutions, Inc., Diversified Group Administrators, Inc., and PPO Management
Solutions, Inc. (whether one or more, the "GUARANTORS") to each execute and
deliver to Bank contemporaneously herewith a guaranty agreement, in form and
substance satisfactory to Bank.

         6. REPRESENTATIONS AND WARRANTIES. Borrower hereby represents and
warrants, and upon each request for an advance under the Credit Facilities,
further represents and warrants, to Bank as follows:

                  (a) Existence. Borrower is a corporation duly organized,
         validly existing and in good standing under the laws of the State of
         Delaware and all other states where it is doing business, and has all
         requisite power and authority to execute and deliver the Loan
         Documents.

                  (b) Binding Obligations. The execution, delivery, and
         performance of this Loan Agreement and all of the other Loan Documents
         by Borrower have been duly authorized by all necessary action by
         Borrower, and constitute legal, valid and binding obligations of
         Borrower, enforceable in accordance with their respective terms, except
         as limited by bankruptcy, insolvency or similar laws of general
         application relating to the enforcement of creditors' rights and except
         to the extent specific remedies may generally be limited by equitable
         principles.

                  (c) No Consent. The execution, delivery and performance of
         this Loan Agreement and the other Loan Documents, and the consummation
         of the transactions contemplated hereby and thereby, do not (i)
         conflict with, result in a violation of, or constitute a default under
         (A) any provision of its articles or certificate of incorporation or
         bylaws, if Borrower is a corporation, or its partnership agreement, if
         Borrower is a partnership, or any agreement or other instrument binding
         upon Borrower, or (B) any law, governmental regulation, court decree or
         order applicable to Borrower, or (ii) require the consent, approval or
         authorization of any third party.

                  (d) Financial Condition. Each financial statement of Borrower
         supplied to the Bank fully discloses and fairly presents Borrower's
         financial condition as of the date of each such statement. There has
         been no material adverse change in such financial condition or results
         of operations of Borrower subsequent to the date of the most recent
         financial statement supplied to the Bank.

                  (e) Litigation. There are no actions, suits or proceedings,
         pending or, to the knowledge of Borrower, threatened against or
         affecting Borrower or the properties of Borrower, before any court or
         governmental department, commission or board, which, if determined
         adversely to Borrower, would have a material adverse effect on the
         financial condition, properties, or operations of Borrower.




LOAN AGREEMENT - Page 3

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                  (f) Taxes; Governmental Charges. Borrower has filed all
         federal, state and local tax reports and returns required by any law or
         regulation to be filed by it and has either duly paid all taxes, duties
         and charges indicated due on the basis of such returns and reports, or
         made adequate provision for the payment thereof, and the assessment of
         any material amount of additional taxes in excess of those paid and
         reported is not reasonably expected.

                  (g) Year 2000 Changes. All devices, systems, machinery,
         information technology, computer software and hardware, and other date
         sensitive technology (jointly and severally the "SYSTEMS") necessary
         for Borrower and its subsidiaries to carry on its business as presently
         conducted and as contemplated to be conducted in the future are Year
         2000 Compliant or will be Year 2000 Compliant within a period of time
         calculated to result in no material disruption of any of Borrower's
         business operations. For purposes of these provisions, "Year 2000
         Compliant" means that such Systems are designed to be used prior to,
         during and after the Gregorian calendar year 2000 A.D. and will operate
         during each such time period without error relating to date data,
         specifically including any error relating to, or the product of, date
         data which represents or references different centuries or more than
         one century. Borrower will make written inquiry of each of its key
         suppliers, vendors, and customers, and will obtain in writing
         confirmations from all such persons, as to whether such persons have
         initiated programs to become Year 2000 Compliant and Borrower
         reasonably believes that all such persons will be or become so
         compliant. For purposes hereof, "key suppliers, vendors, and customers"
         refers to those suppliers, vendors, and customers of Borrower whose
         business failure would, with reasonable probability, result in a
         material adverse change in the business, properties, condition
         (financial or otherwise), or prospects of Borrower. For purposes of
         this paragraph, Bank, as a lender of funds under the terms of the
         Credit Facility, confirms to Borrower that Bank has initiated its own
         corporate-wide Year 2000 program with respect to its lending
         activities.

         7. CONDITIONS PRECEDENT TO ADVANCES. Bank's obligation to make any
advance under this Loan Agreement and the other Loan Documents shall be subject
to the conditions precedent that, as of the date of such advance and after
giving effect thereto (i) all representations and warranties made to Bank in
this Loan Agreement and the other Loan Documents shall be true and correct, as
of and as if made on such date, (ii) no material adverse change in the financial
condition of Borrower since the effective date of the most recent financial
statements furnished to Bank by Borrower shall have occurred and be continuing,
(iii) no event has occurred and is continuing, or would result from the
requested advance, which with notice or lapse of time, or both, would constitute
an Event of Default (as hereinafter defined), and (iv) Bank's receipt of all
Loan Documents appropriately executed by Borrower and all other proper parties.

         8. AFFIRMATIVE COVENANTS. Until (i) the Note and all other obligations
and liabilities of Borrower under this Loan Agreement and the other Loan
Documents are fully paid and satisfied, and (ii) the Bank has no further
commitment to lend hereunder, Borrower agrees and covenants that it will, unless
Bank shall otherwise consent in writing:








LOAN AGREEMENT - Page 4

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                  (a) Accounts and Records. Maintain its books and records in
         accordance with generally accepted accounting principles.

                  (b) Right of Inspection. Permit Bank to visit its properties
         and installations and to examine, audit and make and take away copies
         or reproductions of Borrower's books and records, at all reasonable
         times.

                  (c) Right to Additional Information. Furnish Bank with such
         additional information and statements, lists of assets and liabilities,
         tax returns, and other reports with respect to Borrower's financial
         condition and business operations as Bank may request from time to
         time.

                  (d) Compliance with Laws. Conduct its business in an orderly
         and efficient manner consistent with good business practices, and
         perform and comply with all statutes, rules, regulations and/or
         ordinances imposed by any governmental unit upon Borrower its
         businesses, operations and properties (including, without limitation,
         all applicable environmental statutes, rules, regulations and
         ordinances).

                  (e) Taxes. Pay and discharge when due all of its indebtedness
         and obligations, including, without limitation, all assessments, taxes,
         governmental charges, levies and liens, of every kind and nature,
         imposed upon Borrower or its properties, income, or profits, prior to
         the date on which penalties would attach, and all lawful claims that,
         if unpaid, might become a lien or charge upon any of Borrower's
         properties, income, or profits; provided, however, Borrower will not be
         required to pay and discharge any such assessment, tax, charge, levy,
         lien or claim so long as (i) the legality of the same shall be
         contested in good faith by appropriate judicial, administrative or
         other legal proceedings, and (ii) Borrower shall have established on
         its books adequate reserves with respect to such contested assessment,
         tax, charge, levy, lien or claim in accordance with generally accepted
         accounting principles, consistently applied.

                  (f) Insurance. Maintain insurance, including but not limited
         to, fire insurance, comprehensive property damage, public liability and
         worker's compensation, and, within ten (10) days after the date of this
         Agreement will acquire business interruption and other insurance deemed
         necessary or otherwise required by Bank.

                  (g) Notice of Indebtedness. Promptly inform Bank of the
         creation, incurrence or assumption by Borrower of any actual or
         contingent liabilities not permitted under this Loan Agreement.

                  (h) Notice of Litigation. Promptly after the commencement
         thereof, notify Bank of all actions, suits and proceedings before any
         court or any governmental department, commission or board affecting
         Borrower or any of its properties.

                  (i) Notice of Material Adverse Change. Promptly inform Bank of
         (i) any and all material adverse changes in Borrower's financial
         condition, and (ii) all claims made against Borrower which could
         reasonably be expected to materially affect the financial condition of
         Borrower.






LOAN AGREEMENT - Page 5


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                  (j) Additional Documentation. Execute and deliver, or cause to
         be executed and delivered, any and all other agreements, instruments or
         documents which Bank may reasonably request in order to give effect to
         the transactions contemplated under this Loan Agreement and the other
         Loan Documents.

                  (k) Maintain Control. The Answer Partnership, Ltd., a Texas
         limited partnership, J. Ward Hunt, or any entity owned or controlled by
         J. Ward Hunt shall maintain ownership of not less than 50% of the
         outstanding voting stock of Borrower.

         9. NEGATIVE COVENANTS. Until (i) the Note and all other obligations and
liabilities of Borrower under this Loan Agreement and the other Loan Documents
are fully paid and satisfied, and (ii) the Bank has no further commitment to
lend hereunder, Borrower will not, without the prior written consent of Bank:

                  (a) Nature of Business. Make any material change in the nature
         of its business as carried on as of the date hereof.

                  (b) Liquidations, Mergers, Consolidations. Liquidate, merge or
         consolidate with or into any other entity.

                  (c) Sale of Assets. Sell, transfer or otherwise dispose of any
         of its assets or properties, other than (i) in the ordinary course of
         business and (ii) transfers among Borrower and the Obligated Parties.

                  (d) Liens. Create or incur any lien or encumbrance on any of
         its assets, other than (i) liens and security interests securing
         indebtedness owing to Bank, (ii) liens for taxes, assessments or
         similar charges either (1) not yet due or (2) being contested in good
         faith by appropriate proceedings and for which Borrower has established
         adequate reserves, (iii) liens and security interest existing as of the
         date hereof which have been disclosed to and approved by the Bank in
         writing and (iv) liens and security interests on equipment securing the
         purchase price for such equipment.

                  (e) Indebtedness. Create, incur or assume any indebtedness for
         borrowed money or issue or assume any other note, debenture, bond or
         other evidences of indebtedness, or guarantee any such indebtedness or
         such evidences of indebtedness of others, other than (i) borrowings
         from Bank, (ii) borrowings outstanding on the date hereof and disclosed
         in writing to Bank, and (iii) the Subordinated Debt evidenced by the
         Convertible Subordinated Promissory Notes attached hereto as EXHIBIT
         "A" incurred in connection with the acquisition of subsidiary BHC, Inc.

                  (f) Change in Management. Allow Robert Brooks or J. Ward Hunt
         to cease active participation in the senior management of Borrower.

                  (g) Loans. Make any loans to any person or entity except
         advances of business expenses to employees in the ordinary course of
         business.




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                  (h) Transactions with Affiliates. Enter into any transaction,
         including, without limitation, the purchase, sale or exchange of
         property or the rendering of any service, with any Affiliate (as
         hereinafter defined) of Borrower, except in the ordinary course of and
         pursuant to the reasonable requirements of Borrower's business and upon
         fair and reasonable terms no less favorable to Borrower than would be
         obtained in a comparable arm's-length transaction with a person or
         entity not an Affiliate of Borrower. As used herein, the term
         "AFFILIATE" means any individual or entity directly or indirectly
         controlling, controlled by, or under common control with, another
         individual or entity.

                  (i) Dividends. Borrower agrees not to declare or pay any cash
         dividends on any shares of Borrower's capital stock, make any other
         distributions with respect to any payment on account of the purchase,
         redemption, or other acquisition or retirement of any shares of
         Borrower's capital stock, or make any other distribution, sale,
         transfer or lease of any of Borrower's assets other than in the
         ordinary course of business, unless any such amounts are directly
         utilized for the payment of principal or interest on indebtedness and
         obligations owing from time to time by Borrower to Bank.

         10. FINANCIAL COVENANTS. Until (i) the Note and all other obligations
and liabilities of Borrower under this Loan Agreement and the other Loan
Documents are fully paid and satisfied, and (ii) the Bank has no further
commitment to lend hereunder, Borrower and its subsidiaries, on a consolidated
basis, will maintain the following financial covenants:

                  (a) Minimum Income. Beginning January 1, 1999, Borrower will
         maintain income of not less than $1.00 for each fiscal quarter.

                  (b) Net Worth. Borrower will maintain, at all times, its total
         assets less its total liabilities at not less than $7,900,000.

                  (c) Debt Service. Borrower will maintain, as of the last day
         of each fiscal quarter, a ratio of (i) consolidated net income after
         taxes plus interest expense depreciation, amortization and other
         non-cash expenses for the twelve (12) month period ending with such
         fiscal quarter, less any capital expenditures during such twelve (12)
         month period to (ii) total interest expense and current maturities of
         long term debt and long term capital leases for such twelve (12) month
         period, of not less than 1.25 to 1.0.

                  (d) Funded Debt to Cash Flow. Borrower will maintain, as of
         the end of each fiscal quarter, a ratio of all outstanding debt of
         Borrower at the end of such fiscal quarter, to (ii) earnings before
         depreciation, amortization, and interest expense for the twelve (12)
         month period ending with such fiscal quarter, of not more than 2.5 to
         1.0.

                  (e) Capital Expenditures. Borrower will not make capital
         expenditures in excess of $500,000 during any fiscal year.

                  (f) Current Ratio. At all times, a ratio of (a) current
         assets, (excluding prepaid expenses) to (b) current liabilities of not
         less than 1.5 to 1.0.







LOAN AGREEMENT - Page 7

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                  (g) Maintain Contracts. Borrower shall not allow the net loss,
         in any year (after taking into account revenues from new clients), of
         clients which contributed more than an aggregate amount of $1,500,000
         in revenue to Borrower or its subsidiaries in the previous year.

As used herein, the term "SUBORDINATED DEBT" means any indebtedness owing by
Borrower which has been subordinated by written agreement to all indebtedness
now or hereafter owing by Borrower to Lender, such agreement to be in form and
substance acceptable to Lender. As used herein, "DISTRIBUTIONS" shall mean all
cash or cash equivalent dividends and other distributions made by Borrower to
its shareholders or partners, as the case may be, other than salary, bonuses and
other compensation for services. Unless otherwise specified, all accounting and
financial terms and covenants set forth above are to be determined according to
generally accepted accounting principles, consistently applied.

         11. REPORTING REQUIREMENTS. Until (i) the Note and all other
obligations and liabilities of Borrower under this Loan Agreement and the other
Loan Documents are fully paid and satisfied, and (ii) the Bank has no further
commitment to lend hereunder, Borrower will, unless Bank shall otherwise consent
in writing, furnish to Bank:

                  (a) Interim Financial Statements. As soon as available, and in
         any event within forty-five (45) days after the end of each quarter of
         each fiscal year of Borrower, a consolidated and consolidating balance
         sheet and income statement of Borrower as of the end of such fiscal
         quarter, all in form and substance and in reasonable detail
         satisfactory to Bank and duly certified (subject to year end review
         adjustments) by the President and/or Chief Financial Officer of
         Borrower (i) as being true and correct in all material aspects to the
         best of his or her knowledge, (ii) as having been prepared in
         accordance with generally accepted accounting principles, consistently
         applied, and (iii) as being consistent in all material respects with
         the information submitted by Borrower to the U.S. Securities and
         Exchange Commission pursuant to its Quarterly Report on Form 10QSB.

                  (b) Annual Financial Statements. As soon as available and in
         any event within one hundred twenty (120) days after the end of each
         fiscal year of Borrower, a consolidated and consolidating balance sheet
         and income statement of Borrower as of the end of such fiscal year, in
         each case audited by independent public accountants of recognized
         standing acceptable to Bank.

                  (c) Compliance Certificate. A certificate signed by Chairman,
         President, or Vice President, Finance of Borrower, within forty-five
         (45) days after the end of each quarter of each fiscal year, stating
         that Borrower is in full compliance with all of its obligations under
         this Loan Agreement and all other Loan Documents and is not in default
         of any term or provisions hereof or thereof, and demonstrating
         compliance with all financial ratios and covenants set forth in this
         Loan Agreement.





LOAN AGREEMENT - Page 8
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                  (d) Accounts Aging. An accounts receivable aging report within
         thirty (30) days after the end of each month of each fiscal year, in
         form and detail satisfactory to Bank.

                  (e) Audit Reports. True and complete copies of all audit
         reports submitted to Borrower.

                  (f) Adverse Events. Immediate notice of any Event of Default
         or any event which, with the passing of time or the giving of notice,
         or both, could constitute an Event of Default, and any other event
         which could reasonably be expected to have a material adverse effect
         upon Borrower or any Guarantor.

                  (g) Year 2000 Information. Furnish such additional
         information, statements and other reports with respect to Borrower's
         activities, course of action and progress towards becoming Year 2000
         Compliant as Bank may request from time to time. In the event of any
         change in circumstances that causes or will likely cause any of
         Borrower's representations and warranties with respect to Borrower or
         its subsidiaries being or becoming Year 2000 Complaint to no longer be
         true (hereinafter, referred to as a "CHANGE IN CIRCUMSTANCES") then
         Borrower shall promptly, and in any event within ten (10) days of
         receipt of information regarding a Change in Circumstances, provide
         Bank with written notice (the "Notice") that describes in reasonable
         detail the Change in Circumstances and how such Change in Circumstances
         caused or will likely cause Borrower's representations and warranties
         with respect to being or becoming Year 2000 Compliant to no longer be
         true. Borrower shall, within ten (10) days of a request, also provide
         Bank with any additional information Bank requests of Borrower in
         connection with the Notice and/or a Change in Circumstances.

         12. EVENTS OF DEFAULT. Each of the following shall constitute an "EVENT
OF DEFAULT" under this Loan Agreement:

                  (a) The failure, refusal or neglect of Borrower to pay when
         due any part of the principal of, or interest on, the Note or any other
         indebtedness or obligations owing to Bank by Borrower from time to
         time.

                  (b) The failure of Borrower or any Obligated Party (as defined
         below) to timely and properly observe, keep or perform any covenant,
         agreement, warranty or condition required herein or in any of the other
         Loan Documents, if such failure shall continue for thirty (30) days
         after notice to Borrower of such failure.

                  (c) The occurrence of an event of default under any of the
         other Loan Documents or under any other agreement now existing or
         hereafter arising between Bank and Borrower.





LOAN AGREEMENT - Page 9

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                  (d) Any representation contained herein or in any of the other
         Loan Documents made by Borrower or any Obligated Party is false or
         misleading in any material respect.

                  (e) The occurrence of any event which permits the acceleration
         of the maturity of any indebtedness in excess of $50,000 owing by
         Borrower to any third party under any agreement or understanding unless
         such occurrence is rectified within five (5) days.

                  (f) If Borrower or any Obligated Party: (i) becomes insolvent,
         or makes a transfer in fraud of creditors, or makes an assignment for
         the benefit of creditors, or admits in writing its inability to pay its
         debts as they become due; (ii) generally is not paying its debts as
         such debts become due; (iii) has a receiver, trustee or custodian
         appointed for, or take possession of, all or substantially all of the
         assets of such party, either in a proceeding brought by such party or
         in a proceeding brought against such party and such appointment is not
         discharged or such possession is not terminated within sixty (60) days
         after the effective date thereof or such party consents to or
         acquiesces in such appointment or possession; (iv) files a petition for
         relief under the United States Bankruptcy Code or any other present or
         future federal or state insolvency, bankruptcy or similar laws (all of
         the foregoing hereinafter collectively called "APPLICABLE BANKRUPTCY
         LAW") or an involuntary petition for relief is filed against such party
         under any Applicable Bankruptcy Law and such involuntary petition is
         not dismissed within sixty (60) days after the filing thereof, or an
         order for relief naming such party is entered under any Applicable
         Bankruptcy Law, or any composition, rearrangement, extension,
         reorganization or other relief of debtors now or hereafter existing is
         requested or consented to by such party; (v) fails to have discharged
         within a period of thirty (30) days any attachment, sequestration or
         similar writ levied upon any property of such party; or (vi) fails to
         pay within thirty (30) days any final money judgment against such
         party.

                  (g) The liquidation, dissolution, or, without the prior
         written consent of Bank, which consent shall not be unreasonably
         withheld, the merger or consolidation of Borrower or any Obligated
         Party.

                  (h) Either Robert Brooks or J. Ward Hunt ceases active
         participation in the management of Borrower.

                  (i) The entry of any judgment against Borrower or the issuance
         or entry of any attachment or other lien against any of the property of
         Borrower for an amount in excess of $50,000, if undischarged, unbonded
         or undismissed within thirty (30) days after such entry.

Nothing contained in this Loan Agreement shall be construed to limit the events
of default enumerated in any of the other Loan Documents and all such events of
default shall be cumulative. The term "OBLIGATED PARTY", as used herein, shall
mean any party other than Borrower who secures, guarantees and/or is otherwise
obligated to pay all or any portion of the indebtedness evidenced by the Note.





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         13. REMEDIES. Upon the occurrence of any one or more of the foregoing
Events of Default, (a) the entire unpaid balance of principal of the Note,
together with all accrued but unpaid interest thereon, and all other
indebtedness owing to Bank by Borrower at such time shall, at the option of
Bank, become immediately due and payable without further notice, demand,
presentation, notice of dishonor, notice of intent to accelerate, notice of
acceleration, protest or notice of protest of any kind, all of which are
expressly waived by Borrower, and (b) Bank may, at its option, cease further
advances under the Note provided, however, concurrently and automatically with
the occurrence of an Event of Default under SUBPARAGRAPH (F) in the immediately
preceding paragraph (i) further advances under the Note shall cease, and (ii)
the Note and all other indebtedness owing to Bank by Borrower at such time
shall, without any action by Bank, become due and payable, without further
notice, demand, presentation, notice of dishonor, notice of acceleration, notice
of intent to accelerate, protest or notice of protest of any kind, all of which
are expressly waived by Borrower. All rights and remedies of Bank set forth in
this Loan Agreement and in any of the other Loan Documents may also be exercised
by Bank, at its option to be exercised in its sole discretion, upon the
occurrence of an Event of Default.

         14. RIGHTS CUMULATIVE. All rights of Bank under the terms of this Loan
Agreement shall be cumulative of, and in addition to, the rights of Bank under
any and all other agreements between Borrower and Bank (including, but not
limited to, the other Loan Documents), and not in substitution or diminution of
any rights now or hereafter held by Bank under the terms of any other agreement.

         15. WAIVER AND AGREEMENT. Neither the failure nor any delay on the part
of Bank to exercise any right, power or privilege herein or under any of the
other Loan Documents shall operate as a waiver thereof, nor shall any single or
partial exercise of such right, power or privilege preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. No
waiver of any provision in this Loan Agreement or in any of the other Loan
Documents and no departure by Borrower therefrom shall be effective unless the
same shall be in writing and signed by Bank, and then shall be effective only in
the specific instance and for the purpose for which given and to the extent
specified in such writing. No modification or amendment to this Loan Agreement
or to any of the other Loan Documents shall be valid or effective unless the
same is signed by the party against whom it is sought to be enforced.

         16. BENEFITS. This Loan Agreement shall be binding upon and inure to
the benefit of Bank and Borrower, and their respective successors and assigns,
provided, however, that Borrower may not, without the prior written consent of
Bank, assign any rights, powers, duties or obligations under this Loan Agreement
or any of the other Loan Documents.

         17. NOTICES. All notices, requests, demands or other communications
required or permitted to be given pursuant to this Agreement shall be in writing
and given by (i) personal delivery, (ii) expedited delivery service with proof
of delivery, or (iii) United States mail, postage prepaid, registered or
certified mail, return receipt requested, sent to the intended addressee at the
address set forth on the signature page hereof and shall be deemed to have been
received either, in the case of personal delivery, as of the time of personal
delivery, in the case of expedited delivery service, as of the date of first
attempted delivery at the address and in the 




LOAN AGREEMENT - Page 11


<PAGE>   12


manner provided herein, or in the case of mail, upon deposit in a depository
receptacle under the care and custody of the United States Postal Service.
Either party shall have the right to change its address for notice hereunder to
any other location within the continental United States by notice to the other
party of such new address at least thirty (30) days prior to the effective date
of such new address.

         18. CONSTRUCTION. THIS LOAN AGREEMENT AND THE OTHER LOAN DOCUMENTS HAVE
BEEN EXECUTED AND DELIVERED IN THE STATE OF TEXAS, SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS, AND SHALL BE
PERFORMABLE BY THE PARTIES HERETO IN THE COUNTY IN TEXAS WHERE THE BANK'S
ADDRESS SET FORTH ON THE SIGNATURE PAGE HEREOF IS LOCATED.

         19. INVALID PROVISIONS. If any provision of this Loan Agreement or any
of the other Loan Documents is held to be illegal, invalid or unenforceable
under present or future laws, such provision shall be fully severable and the
remaining provisions of this Loan Agreement or any of the other Loan Documents
shall remain in full force and effect and shall not be affected by the illegal,
invalid or unenforceable provision or by its severance.

         20. EXPENSES. Borrower shall pay all costs and expenses (including,
without limitation, reasonable attorneys' fees) in connection with (i) any
action required in the course of administration of the indebtedness and
obligations evidenced by the Loan Documents, and (ii) any action in the
enforcement of Bank's rights upon the occurrence of Event of Default.

         21. PARTICIPATION OF THE LOANS. Borrower agrees that Bank may, at its
option, sell interests in the Loans and its rights under this Loan Agreement to
a financial institution or institutions and, in connection with each such sale,
Bank may disclose any financial and other information available to Bank
concerning Borrower to each perspective purchaser.

         22. ENTIRE AGREEMENT. This Loan Agreement (together with the other Loan
Documents) contains the entire agreement among the parties regarding the subject
matter hereof and supersedes all prior written and oral agreements and
understandings among the parties hereto regarding same.

         23. CONFLICTS. In the event any term or provision hereof is
inconsistent with or conflicts with any provision of the other Loan Documents,
the terms and provisions contained in this Loan Agreement shall be controlling.

         24. COUNTERPARTS. This Loan Agreement may be separately executed in any
number of counterparts, each of which shall be an original, but all of which,
taken together, shall be deemed to constitute one and the same instrument.

         25. ARBITRATION. Bank and Borrower agree that upon the written demand
of either party, whether made before or after the institution of any legal
proceedings, but prior to the rendering of any judgment in that proceeding, all
disputes, claims and controversies between 






LOAN AGREEMENT - Page 12


<PAGE>   13


them, whether individual, joint, or class in nature, arising from this Loan
Agreement, the Notes or any other Loan Document or otherwise, including, without
limitation, contract disputes and tort claims, shall be resolved by binding
arbitration pursuant to the Commercial Rules of the American Arbitration
Association. Any arbitration proceeding held pursuant to this arbitration
provision shall be conducted in the city nearest the Borrower's address having
an AAA regional office, or at any other place selected by mutual agreement of
the parties. No act to take or dispose of any Collateral shall constitute a
waiver of this arbitration agreement or be prohibited by this arbitration
agreement. The arbitration provision shall not limit the right of either party
during any dispute, claim or controversy to seek, use, and employ ancillary, or
preliminary rights and/or remedies, judicial or otherwise, for the purposes of
realizing upon, preserving, protecting, foreclosing upon or proceeding under
forcible entry and detainer for possession of, any real or personal property,
and any such action shall not be deemed an election of remedies. Such remedies
include, 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 receivership, 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 or when applicable, a judgment by confession of judgment. Any
disputes, claims or controversies concerning the lawfulness or reasonableness of
an act, or exercise of any right or remedy concerning any Collateral, including
any claim to rescind, reform, or otherwise modify any agreement relating to the
Collateral, shall also be arbitrated; provided, however, that no arbitrator
shall have the right or the power to enjoin or restrain any act of either party.
Judgment upon any award rendered by any arbitrator may be entered in any court
having jurisdiction. Nothing in this arbitration provision shall preclude either
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 any action for these purposes.
The Federal Arbitration Act (Title 9 of the United States Code) shall apply to
the construction, interpretation, and enforcement of this arbitration provision.

         26. JURY WAIVER. TO THE EXTENT PERMITTED UNDER APPLICABLE LAW THE
UNDERSIGNED AND BANK (BY ITS ACCEPTANCE HEREOF) HEREBY VOLUNTARILY, KNOWINGLY,
IRREVOCABLY AND UNCONDITIONALLY WAIVE ANY RIGHT TO HAVE A JURY PARTICIPATE IN
RESOLVING ANY DISPUTE (WHETHER BASED UPON CONTRACT, TORT OR OTHERWISE) BETWEEN
OR AMONG THE UNDERSIGNED AND BANK ARISING OUT OF OR IN ANY WAY RELATED TO THIS
DOCUMENT OR ANY OTHER RELATED DOCUMENT. THIS PROVISION IS A MATERIAL INDUCEMENT
TO BANK TO PROVIDE THE FINANCING DESCRIBED HEREIN OR IN THE OTHER LOAN
DOCUMENTS.









LOAN AGREEMENT - Page 13

<PAGE>   14



         If the foregoing correctly sets forth our mutual agreement, please so
acknowledge by signing and returning this Loan Agreement to the undersigned.

                                       Very truly yours,

                                       BANK ONE, TEXAS, N.A.

                                       By: /s/ BURTON FRENCH
                                          --------------------------------------
                                          Burton French, Vice President


                                       BANK'S ADDRESS:

                                       1717 Main Street, 3rd Floor
                                       Dallas, Texas 75201
                                       Attn:  Burton French

         ACCEPTED as of the date first written above.

                                       BORROWER:

                                       MEDICALCONTROL, INC.


                                       By: /s/ J. WARD HUNT
                                          --------------------------------------
                                       Name: J. Ward Hunt
                                            ------------------------------------
                                       Title: President and CEO
                                             -----------------------------------

                                       BORROWER'S ADDRESS:

                                       8625 King George
                                       Suite 300
                                       Dallas, Texas 75235




LOAN AGREEMENT - Page 14