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                                                                   Exhibit 10.39


                                PLEDGE AGREEMENT

      THIS PLEDGE AGREEMENT ("Agreement") effective the 31st day of January,
1999, by and among RainTree Healthcare Corporation, a Delaware corporation,
whose address is 15300 North 90th Street, Suite 100, Scottsdale, Arizona 85260
("Pledgor"), and Norwest Bank Minnesota, National Association, whose address is
Sixth & Marquette, Minneapolis, Minnesota 55479-0069 ("Pledgee").

                                   WITNESSETH:

      WHEREAS, Pledgor is the issuer of those certain 11% Senior Secured Notes
due 2003 (the "Notes") pursuant to that certain Indenture dated as of January
31, 1999 (the "Indenture"), by and among Pledgor, the Guarantors (as defined in
the Indenture), and Pledgee, as trustee under the Indenture;

      WHEREAS, Pledgor, as the owner of (i) 75% of the outstanding capital stock
of Quest Pharmacies, Inc., an Arizona corporation ("Quest"), (ii) an option to
acquire 25% of the outstanding capital stock of Quest (the "Option"), and (iii)
100% of the outstanding capital stock of Sunbelt Therapy Management Services,
Inc., an Arizona corporation ("Sunbelt"), will benefit from the transactions
contemplated by the Indenture and other financial accommodations derived
therefrom and desires to provide the pledge contemplated by this Agreement as
further consideration and inducement to the purchasers of the Notes to enter
into the transactions contemplated by the Indenture.

      WHEREAS, it is a requirement under the Indenture and a condition precedent
to the receipt by Pledgor of the financial accommodations thereunder that
Pledgor execute and deliver this Pledge Agreement and perform hereunder.

       NOW, THEREFORE, in consideration of the foregoing, and other valuable
consideration, the receipt, legal adequacy and sufficiency of which are hereby
acknowledged, Pledgor hereby agrees with Pledgee as follows:

      1. Definitions. All terms used in this Agreement which are not defined
herein, but are defined in the Indenture shall have the respective meanings
ascribed to such terms therein. The term "Pledged Stock" as used herein shall
mean and include all of the issued and outstanding shares of the capital stock
or other securities in Quest and Sunbelt (i) owned by Pledgor, as listed on
Schedule 1, annexed hereto (and any supplemental schedules attached hereto or
delivered to Pledgee from time to time), (ii) acquired by Pledgor upon exercise
of the Option, or (iii) voting trust certificates or other documents of any kind
evidencing any and all ownership or other interests of Pledgor in Quest and
Sunbelt.

      2. Pledge; Rights and Remedies.

      (a) As collateral security for the due payment and performance of all
indebtedness and other liabilities and obligations of Pledgor and the
Guarantors, whether now existing or hereafter arising (all hereinafter called
the "Obligations") provided for in the Indenture, the Notes, the Guarantee, the
Collateral Documents and all instruments, agreements and documents
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executed, issued, and delivered pursuant thereto (all hereinafter called the
"Financing Documents"), Pledgor hereby pledges, assigns, hypothecates, delivers,
and sets over to Pledgee, on behalf of the holders of the Notes, all of
Pledgor's right, title and interest in and to the Pledged Stock, and hereby
grants to Pledgee a security interest in all of its right, title and interest in
and to the Pledged Stock and in the proceeds thereof.

      (b) Upon the exercise of the Option, Pledgor shall deliver to Pledgee any
shares of capital stock of Quest acquired upon such exercise (the "Option
Stock"), with Pledgor's endorsement when necessary, and/or appropriate stock
powers duly executed in blank, to be held by Pledgee, subject to the terms
hereof, as further collateral security for the Obligations. Additionally,
Pledgor shall pledge, assign, hypothecate, deliver, and set over to Pledgee, on
behalf of the holders of the Notes, all of Pledgor's right, title and interest
in and to the Option Stock, and shall grant to Pledgee a security interest in
all of its right, title and interest in and to the Option Stock and in the
proceeds thereof. Upon the exercise of the Option, Pledgor shall also deliver to
Pledgee a supplemental Schedule 1 to this Agreement.

      (c) If Pledgor shall become entitled to receive or shall receive any stock
or voting trust certificate (including, without limitation, any certificate
representing a stock dividend or a distribution in connection with any
reclassification, increase, or reduction of capital), option or rights, whether
as an addition to, in substitution of, or in exchange for any Pledged Stock, or
otherwise, Pledgor shall accept any such instruments as Pledgee's agent, shall
hold them in trust for Pledgee, and shall deliver them forthwith to Pledgee in
the exact form received, with Pledgor's endorsement when necessary, and/or
appropriate stock powers duly executed in blank, to be held by Pledgee, subject
to the terms hereof, as further collateral security for the Obligations.

      (d) Any or all shares of the Pledged Stock held by Pledgee hereunder may,
at the option of Pledgee, be registered in the name of Pledgee or its nominee as
pledgee, and Pledgee or its nominee may thereafter, without notice, and after
the occurrence of any Event of Default defined or specified in the Financing
Documents, exercise all available voting and corporate rights at any meeting of
Quest or Sunbelt and exercise any and all rights of conversion, exchange,
subscription, or any other rights, privileges, or options pertaining to any of
the Pledged Stock as if it were the absolute owner thereof including, without
limitation, the right to receive dividends payable thereon and the right to
exchange, at its discretion, any and all of the Pledged Stock upon the merger,
consolidation, reorganization, recapitalization, or other readjustment of any
corporation issuing any of such securities or upon the exercise by any such
issuer of any right, privilege, or option pertaining to any of the Pledged
Stock, and in connection therewith, to deposit and deliver any and all of the
Pledged Stock with any committee, depository, transfer agent, registrar or other
designated agency upon such terms and conditions as it may determine, all
without liability except to account for property actually received by it, but
Pledgee shall have no duty to exercise any of the aforesaid rights, privileges,
or options and shall not be responsible for any failure or omission to do so or
delay in so doing.

      (e) In the event of the occurrence of any Event of Default defined or
specified in the Financing Documents or other default or breach under the
Obligations, Pledgee shall have the right to require that all cash dividends
payable with respect to any part of the Pledged Stock be


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paid to Pledgee to be held by Pledgee as additional security hereunder until
applied to the Obligations.

      (f) In the event of the occurrence of any Event of Default defined or
specified in the Financing Documents or other default or breach under the
Obligations, Pledgee, without demand of performance or other demand,
advertisement, or notice of any kind (except the notice specified below of the
time and place of public or private sale) to or upon Pledgor or any other person
or entity, including without limitation, any trustee (all and each of which
demands, advertisements and/or notices are, to the extent permitted by law,
hereby expressly waived), may forthwith collect, receive, appropriate, and
realize upon the Pledged Stock, or any part thereof, and/or may forthwith sell,
assign, give an option or options to purchase, contract to sell, or otherwise
dispose of and deliver the Pledged Stock, or any part thereof, in one or more
parcels at public or private sale or sales, in whatever order Pledgee may
select, at any exchange, broker's board or at any of Pledgee's offices of
elsewhere at such prices and on such terms (including, without limitation, a
requirement that any purchaser of all or any part of the Pledged Stock shall be
required to purchase the securities constituting the Pledged Stock for
investment and without any intention to make a distribution thereof) as it may
deem best, for cash or on credit or for future delivery without assumption of
any credit risk, with the right of Pledgee or any purchaser upon any such sale
or sales, whether public or private, to purchase the whole or any part of the
Pledged Stock so sold, free of any right or equity of redemption in Pledgor,
which right or equity is hereby expressly waived and released.

      (g) The proceeds of any collection, recovery, receipt, appropriation,
realization, sale or other disposition, shall be applied as follows:

            First, to the reasonable costs and expenses of every kind incurred
      in connection therewith or incidental to the care, safekeeping, or
      otherwise of any and all of the Pledged Stock or in any way relating to
      the rights of Pledgee hereunder, including reasonable attorneys' fees and
      legal expenses.

            Second, to the satisfaction of the Obligations in such order as set
      forth in the Indenture.

            Third, to the payment of any other amounts required by applicable
      law; and

            Fourth, to Pledgor, to the extent of the surplus proceeds, if any.
      Pledgee shall have no duty to account to Pledgor unless a surplus exists
      upon liquidation of the Pledged Stock and any other collateral.

      (h) Pledgee need not give more than five (5) business days' notice of the
time and place of any public sale or of the time after which a private sale may
take place and such notice shall be deemed to be reasonable notification of such
matters.

      3. Rights of Pledgor. Unless and until an Event of Default as defined in
the Financing Documents or other default or breach under the Obligations shall
have occurred and be continuing, Pledgor shall be entitled:


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      (a) To vote all or any part of the Pledged Stock at any and all
shareholder meetings of Quest and/or Sunbelt, as the case may be, and to execute
consents in respect thereof, and to consent to, ratify, or waive notice of any
or all shareholder meetings of Quest and/or Sunbelt, as the case may be, with
the same force and effect as if this Pledge Agreement had not been made and, if
necessary and upon the receipt of the written request from Pledgor thereof,
Pledgee shall from time to time execute and deliver appropriate proxies for that
purpose, provided that Pledgor covenants and agrees not to vote the Pledged
Stock in a manner which would create an Event of Default or create circumstances
which, with the passage of time and/or the giving of notice, would create an
Event of Default under the Financing Documents, the Obligations or any other
documents related thereto, and

      (b) To receive and collect or to have paid overall dividends declared or
paid on the Pledged Stock, except (i) dividends or distributions constituting
stock dividends, (ii) dividends or distributions in kind, or (iii) liquidating
dividends (either partial or complete), provided that any and all such excepted
dividends and distributions shall constitute additional collateral for the
purposes of this Pledge Agreement and shall be delivered and pledged with
Pledgee in accordance with Section 2(c) hereof.

      4. Representations. Pledgor represents and warrants that;

      (a) Pledgor is, as of the date hereof, the legal and beneficial owner of
all of the Pledged Stock and the legal owner of the Option. The Pledged Stock
represents 75% and 100%, respectively, of all of the outstanding shares of
capital stock of Quest and Sunbelt, and, other than the Option and the Option
Stock, there are no other securities or voting trust certificates or other
documents of any kind evidencing any ownership or other interest in Quest and
Sunbelt. No person or entity other than Pledgor has any subscription, warrant or
other right to acquire or reserve any of the foregoing.

      (b) All of the shares of the Pledged Stock have been duly and validly
issued, are fully paid and non-assessable, and are owned by Pledgor free and
clear of any pledge, mortgage, hypothecation, lien, charge, encumbrance, or any
security interest in such shares or the proceeds thereof except for the security
interest granted to Pledgee hereunder.

      (c) No authorization, approval or other action by, and no notice to or
filing with, any governmental authority or regulatory body is required to be
obtained or made by Pledgor either (i) for the pledge by Pledgor of the Pledged
Stock pursuant to this Agreement or for the execution, delivery or performance
of this Agreement by Pledgor, or (ii) for the exercise by Pledgee of the voting
or other rights provided for in this Agreement or the remedies in respect of the
Pledged Stock pursuant to this Agreement, subject to applicable state and
federal securities laws.

      (d) Neither the execution or delivery of this Agreement, nor the
consummation of the transactions contemplated hereby, nor the compliance with or
performance of the terms and conditions of this Agreement by Pledgor is
prevented by, limited by, conflicts with or will result in the breach or
violation of or a default under the terms, conditions or provisions of any
material mortgage, security agreement, indenture, evidence of indebtedness, loan
or financing agreement,


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trust agreement, stockholder agreement, or other agreement or instrument to
which Pledgor is a party or by which it is bound.

      (e) Any assignee of all or any portion of the Pledged Stock is entitled to
receive payments with respect thereto without any defense, counterclaim,
set-off, abatement, reduction, recoupment or other claims arising out of the
action of Pledgor.

      (f) There are no actions, suits or proceedings (whether or not purportedly
on behalf of Pledgor) pending or, to the knowledge of Pledgor, threatened or
affecting Pledgor that involve the Pledged Stock.

      (g) All consents or approvals, if any, required as a condition precedent
to or in connection with the due and valid execution, delivery and performance
by Pledgor of this Agreement have been obtained, subject to applicable state and
federal securities laws.

      5. Covenants.

      (a) Pledgor hereby covenants that so long as the Obligations shall be
outstanding and unpaid, in whole or in part, Pledgor will not, without the prior
written consent of Pledgee, sell, convey, or otherwise dispose of any shares of
the Pledged Stock, the Option, the Option Stock or any interest herein, nor will
Pledgor create, incur, or permit to exist any pledge, mortgage, lien, charge,
encumbrance, or any security interest whatsoever with respect to any of the
Pledged Stock, the Option, the Option Stock or the proceeds thereof other than
that created or permitted by the Financing Documents or hereby.

      (b) Pledgor warrants and will defend Pledgee's right, title, special
property and security interest in and to the Pledged Stock against the claims of
any person, firm, corporation, or other entity.

      6. Sale of Pledged Stock. Pledgor recognizes that Pledgee may be unable to
effect a public sale of all or a part of the Pledged Stock, and may be compelled
to resort to one or more private sales to a restricted group of purchasers who
will be obligated to agree, among other things, to acquire such securities for
their own account, for investment and not with a view to the distribution or
resale thereof. Pledgor acknowledges that any such private sales may be at
prices and on terms less favorable to the seller than if sold at public sales
and agrees that such private sales shall be deemed to have been made in a
commercially reasonable manner, and that Pledgee has no obligation to delay sale
of any such securities for the period of time necessary to permit the issuer of
such securities to register such securities for public sale under the Securities
Act.

      7. Cooperation. Pledgor shall at any time and from time to time, upon
request of Pledgee, execute and deliver such further documents and do such
further acts and things as Pledgee may reasonably request in order to effectuate
the purposes of this Pledge Agreement, including, without limitation, delivering
to Pledgee on the date hereof or at any time hereafter irrevocable proxies in
respect of the Pledged Stock in the form of Exhibit A annexed hereto.


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      8. General.

      (a) Beyond the exercise of reasonable care to assure the safe custody of
the Pledged Stock while held hereunder, Pledgee shall have no duty or liability
to preserve rights pertaining thereto and shall be relieved of all
responsibility for the Pledged Stock upon surrendering it to Pledgor.

      (b) No course of dealing between Pledgor and Pledgee, nor any failure to
exercise, nor any delay in exercising, on the part of Pledgee, any right, power,
or privilege, whether now existing or hereafter arising hereunder or under the
Financing Documents or the Obligations, shall operate as a waiver thereof; nor
shall any single or partial exercise or any right, power, or privilege hereunder
or thereunder preclude any other or further exercise thereof or the exercise of
any other right, power, or privilege.

      (c) The rights and remedies herein provided, and provided in the Financing
Documents and in all other agreements, instruments, and documents delivered or
to be delivered pursuant to any of the foregoing or the Obligations, are
cumulative and are in addition to, and not exclusive of, any rights or remedies
provided by law, including without limitation, the rights and remedies of a
secured party under the Uniform Commercial Code.

      (d) The provisions of this Pledge Agreement are severable, and if any
clause or provision shall be held invalid or unenforceable in whole or in part
in any jurisdiction, then such invalidity or unenforceability shall affect only
such clause or provision, or part thereof, in such jurisdiction, and shall not
in any manner affect such clause or provision in any other jurisdiction, or any
other clause or provision of this Pledge Agreement in any jurisdiction.

      (e) This Pledge Agreement shall inure to the benefit of, and be binding
upon, the successors and assigns of the parties hereto. Notwithstanding the
foregoing, Pledgor shall not have the right to assign or delegate any of its
rights or obligations hereunder without the prior written consent of Pledgee,
and any purported assignment or delegation in the absence of such consent shall
be void.

      (f) This Pledge Agreement shall be governed by and construed in accordance
with the laws of the State of Arizona.

      (g) Pledgor recognizes that the Holders of the Notes have relied on the
pledge and security interest granted herein by Pledgor in extending credit and
making the financial accommodations to the Pledgor, and Pledgor agrees that such
reliance by the Holders of the Notes shall be sufficient consideration for this
pledge.

      (h) This Agreement may be signed in any number of counterparts with the
same effect as if the signatures thereto and hereto were upon the same
instrument.

      (i) The section headings used herein are for convenience only and shall
not be read or construed as limiting the substance or generality of this
Agreement.

      (j) All notices, requests, approvals, consents and other communications
required or permitted to be made hereunder shall, except as otherwise provided,
be in writing and may be


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delivered personally or sent by telegram, telecopy, facsimile, telex, first
class mail or overnight courier, postage prepaid, to the parties addressed as
follows:

            To Pledgor:             RainTree Healthcare Corporation
                                    15300 North 90th Street
                                    Suite 100
                                    Scottsdale, Arizona 85260

                                    With a copy to:

                                    Squire, Sanders & Dempsey L.L.P.
                                    Two Renaissance Square
                                    40 North Central Avenue, Suite 2700
                                    Phoenix, Arizona 85004
                                    Attn:  Christopher D. Johnson, Esq.

            To Pledgee:

                                    Norwest Bank Minnesota, National Association
                                    Corporate Trust Services
                                    Sixth & Marquette
                                    Minneapolis, Minnesota  55479-0069

      Such notices, requests and other communications sent as provided
hereinabove shall be effective when received by the addressee thereof, unless
sent by registered or certified mail, postage prepaid, in which case they shall
be effective exactly three business days after being deposited in the United
States mail. The parties hereto may change their addresses by giving notice
thereof to the other parties hereto in conformity with this section.

                            [SIGNATURE PAGE FOLLOWS]


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      IN WITNESS WHEREOF, the parties have caused this Pledge Agreement to be
duly executed and delivered as of the day and first year first written above.

                                    RAINTREE HEALTHCARE CORPORATION
                                                          (PLEDGOR)

                                    By: _______________________________________
                                    Name:    Clayton Kloehr
                                    Title:   Senior Vice President - Finance
                                             and Treasurer


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<PAGE>   9
                                    NORWEST BANK MINNESOTA, NATIONAL
                                    ASSOCIATION
                                                           (PLEDGEE)

                                    By:   _____________________________________
                                    Name: _____________________________________
                                    Title:_____________________________________


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<PAGE>   10
      Schedule 1 to Pledge Agreement dated January 31, 1999, from Raintree
Healthcare Corporation to Norwest Bank Minnesota, National Association.

                              LIST OF PLEDGED STOCK

<TABLE>
<CAPTION>
      NAME OF ISSUER              CLASS OF SHARES            NUMBER OF SHARES
      --------------              ---------------            ----------------
<S>                               <C>                   <C>
Quest Pharmacies, Inc., an        Common                  7,500 (Cert. No. 1)
Arizona corporation

Sunbelt Therapy Management        Common                 10,000 (Cert. No. C - 1)
Services, Inc., an Arizona
corporation
</TABLE>



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                                    Exhibit A

                                IRREVOCABLE PROXY

      KNOW ALL MEN BY THESE PRESENTS that the undersigned does hereby make,
constitute and appoint Norwest Bank Minnesota, National Association (the
"Pledgee") and each of Pledgee's officers and employees, its true and lawful
attorneys, for it and in its name, place and stead, to act as its proxy in
respect of all of its shares of capital stock of Quest Pharmacies, Inc., an
Arizona corporation ("Quest"), and Sunbelt Therapy Management Services, Inc., an
Arizona corporation ("Sunbelt") (Quest and Sunbelt are hereinafter referred to
as the "Corporation"), which the undersigned now or hereafter may own or hold,
including, without limitation, the right, on behalf of the undersigned, to
demand the call by any proper officer of the Corporation pursuant to the
provisions of its Articles of incorporation or By-Laws and as permitted by law
of a meeting of its shareholders and at any such meeting of shareholder, annual,
general or special, to vote for the transaction of any and all business that may
come before such meeting, or at any adjournment thereof, including, without
limitation, the right to vote for (i) the consolidation merger or other
consolidation with or into the Corporation, (ii) the sale of all or any part of
the assets of the Corporation and/or (iii) the liquidation and dissolution of
the corporation; giving and granting to its said attorneys full power and
authority to do and perform each and every act and thing whether necessary or
desirable to be done in and about the premises, as fully as the undersigned
might or could do if personally present with full power of substitution,
appointment and revocation, hereby ratifying and confirming all that the
undersigned's said attorneys shall do or cause to be done by virtue hereof.

      This Proxy is given to Pledgee and to its officers and employees in
consideration of certain obligations of the Corporation and the undersigned to
Pledgee, and in order to carry out the covenant of the undersigned contained in
a certain Pledge Agreement of even date herewith with Pledgee. This Proxy is
coupled with an interest, shall not be revocable or revoked by the undersigned,
shall be binding upon successors and assigns of the undersigned until the
payment in full of all of the indebtedness, obligations or liabilities to
Pledgee of the Corporation, and may be exercised only after a default in payment
of principal or interest when due of any such indebtedness or the occurrence of
any other Event of Default as defined or specified in the Financing Documents,
or other default or breach under the Obligations, referred to in the Pledge
Agreement.

      IN WITNESS WHEREOF, the undersigned has executed this Irrevocable Proxy
this 31st day of January, 1999.

                                    RAINTREE HEALTHCARE CORPORATION

                                    By:   _____________________________________
                                    Name: _____________________________________
                                    Title:_____________________________________


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