Document:

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                                                                    EXHIBIT 4.3

                    AMENDMENT TO CONVERTIBLE PROMISSORY NOTE

         THIS AMENDMENT (the "Amendment") to that certain Convertible
Promissory Note (the "Note"), dated June 30, 2001, in the original principal
amount of $_________, is made as of this 31st day of March, 2003, by and
between CONTINUCARE CORPORATION, a Florida corporation (the "Company") and
_______________ (the "Holder").

                                    RECITALS

         WHEREAS, in accordance with Article VII of the Note, the Company and
the Holder desire to amend the Note to (i) revise Schedule I, the schedule of
payments of principal, (ii) extend the Maturity Date (as defined below) of the
Note to October 31, 2006, and (iii) increase the interest rate on the last
installment payment of principal set forth on Schedule I to the Note from 7%
per annum to 9% per annum.

         NOW, THEREFORE, in consideration of the premises and for other good
and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

         1.       In Section 1 of the Note, the definition of "Maturity Date"
is hereby amended by deleting such definition in its entirety and substituting
therefor a new definition to read as follows:

                  "Maturity Date shall mean October 31, 2006."

         2.       In Section 1 of the Note, the following definitions shall be
added:

                           "First Installment" shall mean the aggregate
         principal amount of $______________ due and payable by the Company to
         the Holder on October 31, 2004, as set forth on Schedule 1 to this
         Note.

                           "Second Installment" shall mean the aggregate
         principal amount of $______________ due and payable by the Company to
         the Holder on October 31, 2005, as set forth on Schedule 1 to this
         Note.

                           "Third Installment" shall mean the aggregate
         principal amount of $______________ due and payable by the Company to
         the Holder on October 31, 2006, as set forth on Schedule 1 to this
         Note.

         3.       Section 2.1(a) of the Note is hereby amended by deleting such
Section 2.1(a) in its entirety and substituting therefor a new Section 2.1(a)
to read as follows:

                  "Section 2.1      Interest.

                           (a)      This Security shall bear interest as
         follows (each referred to as a "Coupon Rate"): (i) 7% per annum on the
         First Installment and Second Installment, and (ii) effective as of
         April 1, 2003, 9% per annum on the Third

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         Installment, until such installment of principal becomes due and
         payable, and on any overdue installment of principal and (to the
         extent that payment of such interest is enforceable under applicable
         law) on any overdue installment of interest at the applicable Coupon
         Rate, compounded quarterly, payable quarterly in arrears on July 31,
         October 31, January 31 and April 30 of each year (each, an "Interest
         Payment Date") commencing on January 31, 2002, to the Person in whose
         name this Security or any Predecessor Security is registered, at the
         close of business on the regular record date for such interest
         installment, which shall be July 15, October 15, January 15 and April
         15 (whether or not a Business Day), as the case may be, next preceding
         such Interest Payment Date (each a "Regular Record Date").

         4.       Schedule I of the Note is hereby amended by deleting such
Schedule I in its entirety and substituting therefor a new schedule to read as
follows:

                                  "Schedule I

                              Payment of Principal

<TABLE>
<CAPTION>
                      Date              Amount of Principal Matured

                    <S>                 <C>
                    10/31/2004                   $

                    10/31/2005                   $

                    10/31/2006                   $
</TABLE>

         5.       Except as specifically amended hereby, the Note is and
remains unmodified and in full force and effect and is hereby ratified and
confirmed.

         6.       This Amendment shall be deemed a contract made under the laws
of the State of Florida and for all purposes shall be governed by and construed
in accordance with the laws of such State applicable to contracts made and to
be performed entirely within such State.

         7.       This Amendment may be executed in counterparts and each of
such counterparts shall for all purposes be deemed to be an original, and such
counterparts shall constitute but one and the same instrument.

                                   * * * * *

                                      -2-
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         IN WITNESS WHEREOF, the parties have executed this Amendment as of the
date first written above.

                           THE COMPANY:

                           CONTINUCARE CORPORATION

                           By:
                              -------------------------------------------------
                           Name: Spencer Angel
                           Title: Chief Executive Officer and President

                           HOLDER:

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

                                      -3-<PAGE>
                                                                   EXHIBIT 10.1

                                   AGREEMENT

         THIS AGREEMENT, dated as of March 31, 2003, by and among Continucare
Corporation (the "Company"), a Florida corporation, Phillip Frost, M.D., an
individual and principal shareholder of the Company ("Frost"), Frost Gamma
Investments Trust (the "Gamma Trust") and Frost Nevada Investments Trust (the
"Nevada Trust").

                                   WITNESSETH

         WHEREAS, the Company and Merrill Lynch Business Financial Services
Inc. ("Lender") have agreed to amend that certain WCMA Loan and Security
Agreement, dated as of March 9, 2000, to, among other things, extend the
maturity date of the loan from March 31, 2003 to March 31, 2004 (the "Loan");

         WHEREAS, Frost personally guaranteed the Loan in March 2000, however,
such guarantee will expire on March 31, 2003;

         WHEREAS, as an inducement to, and as a condition precedent to the
Lender agreeing to extend the maturity date of the Loan, the Lender requires
that Frost execute and deliver a personal guarantee, whereby Frost shall
continue to guarantee the payment when due and performance of the Loan (the
"Guarantee");

         WHEREAS, Frost has agreed to deliver the Guarantee in consideration of
the Company issuing to the Gamma Trust 1,500,000 shares of common stock and
increase the interest rate of that certain convertible promissory note in the
principal amount of $797,162, dated July 31, 2001 (the "Frost Note"), from 7%
per annum to 9% per annum.

         WHEREAS, if the maturity date of the Loan is not extended, the Company
will be in default of the Loan;

         WHEREAS, the Company has considered various alternatives to deal with
the Loan, including, among other things, obtaining additional third-party
financing; however, due to the Company's current cash flow issues, the Company
has not been able to secure additional financing;

         WHEREAS, the Company is an obligor under a series of convertible
promissory notes, dated June 30, 2001, in the aggregate principal amount of
$3,407,926.84 payable to entities (collectively the "Pecks Entities")
affiliated with Pecks Management, Ltd. (collectively the "Pecks Notes");

         WHEREAS, the Company is an obligor under a convertible promissory
note, dated June 30, 2001, in the principal amount of $504,878.05 payable to
Carret & Company (the "Carret Note");

         WHEREAS, the Pecks Entities and Carret & Company have agreed to extend
the maturity dates under the Pecks Notes and Carret Note to October 31, 2006,
and to defer the due dates for and make changes to the annual principal
installments under the Pecks Notes and Carret

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Note, in consideration of increasing the interest rate on the last installment
of the Pecks Notes and Carret Note from 7% to 9% and issuing 300,000 and 44,400
shares of the Company's common stock to the Pecks Entities and Carret &
Company, respectively;

         WHEREAS, upon due consideration and discussions regarding these
issues, and exploring the costs and benefits and availability (or lack thereof)
of other alternatives, the Board of Directors believes that it is in the best
interest of the Company and its shareholders to enter into this Agreement.

         NOW, THEREFORE, in consideration of the foregoing, the mutual
covenants and agreement set forth, and other good and valuable consideration,
the receipt of which is hereby acknowledged, the parties hereto agree as
follows:

SECTION 1.        ISSUANCE OF SHARES

         1.1      Description of Transaction. In exchange for the Guarantee,
the Company agrees to (i) issue to the Gamma Trust 1,500,000 shares of the
Company's common stock (the "Shares") and (ii) amend the Frost Note, in the
form attached hereto as Exhibit A (the "Frost Note Amendment"), to, effective
as of April 1, 2003, increase the interest rate of the Frost Note from 7% per
annum to 9% per annum.

         1.2      Closing. The closing (the "Closing") of this transaction
shall be effective on March 31, 2003 (the "Effective Date"). Subsequent to
Frost's execution of the Guarantee, the following documents shall be delivered:
(i) the Company shall direct its transfer agent to deliver stock certificates
to the Gamma Trust representing an aggregate of 1,500,000 shares of the
Company's Common Stock, and (ii) the Company shall deliver to Frost the Frost
Note Amendment.

SECTION 2.        REPRESENTATIONS AND WARRANTIES OF THE COMPANY

         The Company hereby represents and warrants to Frost the following:

         2.1      Authorization and Non-Contravention. This Agreement is a
valid and binding obligation of the Company, enforceable against the Company in
accordance with its terms, except as such enforceability may be limited by
bankruptcy laws and general principles of equity. The execution, delivery and
performance of this Agreement and the issuance of the Shares, have been duly
authorized by all necessary action of the Company.

SECTION 3.        REPRESENTATIONS AND WARRANTIES OF FROST, THE GAMMA TRUST AND
                  THE NEVADA TRUST

         Each of Frost, the Gamma Trust and the Nevada Trust hereby represents
and warrants to the Company the following:

         3.1      Authorization and Non-Contravention. This Agreement is a
valid and binding obligation of Frost, the Gamma Trust and the Nevada Trust,
enforceable against Frost, the

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Gamma Trust and the Nevada Trust in accordance with its terms, except as such
enforceability may be limited by bankruptcy laws and general principles of
equity.

         3.2      Investment Representations.

                  (a)      The Gamma Trust is acquiring the Shares for its own
account, for investment. Each of Frost, the Gamma Trust and the Nevada Trust
has had access to all information deemed material with respect to an
acquisition of the Shares.

                  (b)      Each of Frost, the Gamma Trust and the Nevada Trust
understands and acknowledges that the Shares have not been registered under the
Securities Act, or the securities laws of any state or foreign jurisdiction
and, unless so registered, may not be offered, sold, transferred, or otherwise
disposed of except pursuant to an exemption from, or in a transaction not
subject to, the registration requirements of the Securities Act and any
applicable securities laws of any state or foreign jurisdiction.

                  (c)      Each of Frost, the Gamma Trust and the Nevada Trust
understands that the Shares issued pursuant to this Agreement will be in
unregistered form only and that any certificates delivered to it in respect of
the Securities will bear a legend substantially to the following effect:

         THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
         REGISTERED UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE
         "SECURITIES ACT"), OR ANY STATE SECURITIES LAW, AND SUCH SECURITIES
         MAY NOT BE OFFERED, SOLD, TRANSFERRED, PLEDGED, HYPOTHECATED, OR
         OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION
         STATEMENT OR PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT
         SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND
         APPLICABLE STATE SECURITIES LAWS.

SECTION 4.        GENERAL

         4.1      Amendments, Waivers and Consents. No failure or delay on the
part of any party hereto in exercising any right, power or remedy hereunder
shall operate as a waiver thereof. The remedies provided for herein are
cumulative and are not exclusive of any remedies that may be available to any
party hereto at law or in equity or otherwise. This Agreement may be amended
only with the prior written consent of the Company and Frost.

         4.2      Governing Law. This Agreement shall be deemed to be a
contract made under, and shall be construed in accordance with, the laws of the
State of Florida, without giving effect to conflicts of laws principles
thereof.

         4.3      Section Headings. The descriptive headings in this Agreement
have been inserted for convenience only and shall not be deemed to limit or
otherwise affect the construction of any provision thereof or hereof.

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         4.4      Counterparts. This Agreement may be executed simultaneously
in any number of counterparts, each of which when so executed and delivered
shall be taken to be an original; but such counterparts shall together
constitute but one and the same document.

         4.5      Notices and Demands. Any notice or demand which is required
or provided to be given under this Agreement shall be deemed to have been
sufficiently given and received for all purposes when received and may be
delivered by hand, telecopy, telex or other method of facsimile, certified or
registered mail, postage and charges prepaid, return receipt requested, or by
overnight delivery.

         4.6      Severability. Each provision of this Agreement shall be
interpreted in such a manner as to be effective and valid under applicable law,
but if any provision of this Agreement shall be deemed prohibited or invalid
under such applicable law, such provision shall be ineffective only to the
extent of such prohibition or invalidity, and such prohibition or invalidity
shall not invalidate the remainder of such provision or the other provisions of
this Agreement.

         4.7      Integration. This Agreement, including the exhibits,
documents and instruments referred to herein or therein, constitutes the entire
agreement, and supersedes all other prior agreements and understandings, both
written and oral, among the parties with respect to the subject matter hereof,
including, without limitation, the letter of intent between the parties hereto
in respect of the transactions contemplated herein.

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement
effective on the date first written above.

                                    /s/ Phillip Frost, M.D.
                                    -------------------------------------------
                                    Phillip Frost, M.D., individually

                                    FROST GAMMA INVESTMENTS TRUST

                                    By:    /s/ Phillip Frost, M.D.
                                       ----------------------------------------
                                    Name: Phillip Frost, M.D.
                                    Title: Trustee

                                    FROST NEVADA INVESTMENTS TRUST

                                    By:    /s/ Phillip Frost, M.D.
                                       ----------------------------------------
                                    Name: Phillip Frost, M.D.
                                    Title: Trustee

                                    CONTINUCARE CORPORATION

                                    By:     /s/ Spencer J. Angel
                                       ----------------------------------------
                                       Spencer J. Angel, President

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                                   EXHIBIT A

                              FROST NOTE AMENDMENT

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