<PAGE>

                                                                     EXHIBIT 4.3

         THIS SECURITY IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE
HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITORY OR A
NOMINEE THEREOF. THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A
SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE
REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITORY OR A NOMINEE
THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

                          MEDCO HEALTH SOLUTIONS, INC.

                          FORM OF ___ % NOTES DUE 2012

CUSIP No. _____________

No. ___                                                        $_______________

         Medco Health Solutions, Inc., a corporation duly organized and existing
under the laws of the State of Delaware (herein called the "Company", which term
includes any successor Person under the Indenture hereinafter referred to), for
value received, hereby promises to pay to CEDE & CO., or registered assigns, the
principal sum of _________________ Dollars on ________________, 2012, and to pay
interest thereon from _____________, 2002 or from the most recent Interest
Payment Date to which interest has been paid or duly provided for, semi-annually
on _____________ and _________________ in each year, commencing _______________,
2003, at the rate of ____ % per annum, until the principal hereof is paid or
made available for payment, provided, however, that any principal and premium,
and any such installment of interest, which is overdue shall bear interest at
the rate of ___% per annum (to the extent that the payment of such interest
shall be legally enforceable), from the dates such amounts are due until they
are paid or made available for payment, and such interest shall be payable on
demand. The interest so payable, and punctually paid or duly provided for, on
any Interest Payment Date will, as provided in such Indenture, be paid to the
Person in whose name this Security (or one or more Predecessor Securities) is
registered at the close of business on the Regular Record Date for such
interest, which shall be the ________________ or _______________________
(whether or not a Business Day), as the case may be, next preceding such
Interest Payment Date. Any such interest not so punctually paid or duly provided
for will forthwith cease to be payable to the Holder on such Regular Record Date
and may either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date for the payment of such Defaulted Interest to

<PAGE>


be fixed by the Trustee, notice whereof shall be given to Holders of Securities
of this series not less than 10 days prior to such Special Record Date, or be
paid at any time in any other lawful manner not inconsistent with the
requirements of any securities exchange on which the Securities of this series
may be listed, and upon such notice as may be required by such exchange, all as
more fully provided in said Indenture.

         Payment of the principal of (and premium, if any) and interest on this
Security will be made at the office or agency of the Company maintained for that
purpose in The City of New York, New York, in such coin or currency of the
United States of America as at the time of payment is legal tender for payment
of public and private debts.

         Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

         Unless the certificate of authentication hereon has been executed by
the Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

         IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated:

                                           Medco Health Solutions, Inc.

                                           By:  ____________________________
                                                Name:
                                                Title:

Attest:
_________________________
Name:
Title:

                                      -2-

<PAGE>

         This is one of the Securities of the series designated therein referred
to in the within-mentioned Indenture.

                                           U.S. Bank Trust National Association,
                                           As Trustee

                                           By: ____________________________
                                               Authorized Officer

                                      -3-

<PAGE>

         This Security is one of a duly authorized issue of securities of the
Company (herein called the "Securities"), issued and to be issued in one or more
series under an Indenture, dated as of ___________, 2002 (herein called the
"Indenture", which term shall have the meaning assigned to it in such
instrument), between the Company and U.S. Bank Trust National Association, as
Trustee (herein called the "Trustee", which term includes any successor trustee
under the Indenture), and reference is hereby made to the Indenture for a
statement of the respective rights, limitations of rights, duties and immunities
thereunder of the Company, the Trustee and the Holders of the Securities and of
the terms upon which the Securities are, and are to be, authenticated and
delivered. This Security is one of the series designated on the face hereof.

         The Securities of this series are subject to redemption at any time,
upon not less than 30 days' notice by mail, as a whole or from time to time in
part, at the election of the Company (provided, however, that, if the Company
shall have elected pursuant to the Indenture to defease the entire indebtedness
of this Security or certain restrictive covenants and Events of Defaults with
respect to this Security, prior to making such election to redeem the Securities
it shall have deposited in trust amounts sufficient to pay the Redemption
Price), on any date prior to their Stated Maturity at a Redemption Price equal
to the greater of (i) 100% of the principal amount of such Securities to be
redeemed, plus accrued interest thereon to the Redemption Date and (ii) as
determined by a Treasury Dealer (as defined below), whose determination shall be
binding absent manifest error, the sum of the present values of the remaining
scheduled payments of principal and interest thereon, assuming for this purpose
that the Securities remain outstanding until maturity (not including any portion
of such payments of interest accrued as of the Redemption Date) discounted to
the Redemption Date on a semiannual compounding basis (assuming a 360-day year
consisting of twelve 30-day months) at the Treasury Rate (as defined below),
plus ______ basis points, together in the case of any such redemption with
accrued interest to the Redemption Date, but interest installments whose Stated
Maturity is on or prior to such Redemption Date will be payable to the Holders
of such Securities, or one or more Predecessor Securities, of record at the
close of business on the relevant Record Dates referred to on the face hereof,
all as provided in the Indenture.

         "Treasury Rate" means the semiannual equivalent yield to maturity of
the Treasury Security referred to below that corresponds to the Treasury Price
referred to below (calculated in accordance with standard market practice and
computed as of the second trading day preceding the Redemption Date). "Treasury
Security" means the United States Treasury security that the Treasury Dealer
determines would be appropriate to use, at the time of determination and in
accordance with standard market practice, in pricing the Securities being
redeemed in a tender offer based on a spread to United States Treasury yields.
"Treasury Price" means the bid-side price for the Treasury Security as of the
third

                                      -4-

<PAGE>

trading day preceding the Redemption Date, as set forth in the daily statistical
release (or any successor release) published by the Federal Reserve Bank of New
York on that trading day and designated "Composite 3:30 p.m. Quotations for
U.S. Government Securities", except that (i) if that release (or any successor
release) is not published or does not contain that price information on that
trading day; or (ii) if the Treasury Dealer determines that price information is
not reasonably reflective of the actual bid-side price for the Treasury Security
prevailing at 3:30 p.m., New York City time, on that trading day, then Treasury
Price will instead mean the bid-side price for the Treasury Security at or
around 3:30 p.m., New York City time, on that trading day (expressed on a next
trading day settlement basis) as determined by the Treasury Dealer through such
alternative means as the Treasury Dealer considers to be appropriate under the
circumstances. "Treasury Dealer" means _______________________ (or its
successor) or, if ________________________ (or its successor) refuses to act as
Treasury Dealer for these purposes or ceases to be a primary U.S. Government
securities dealer, another nationally recognized investment banking firm that is
a primary U.S. Government securities dealers specified by the Company for these
purposes.

         In the event of redemption of this Security in part only, a new
Security or Securities of this series and of like tenor for the unredeemed
portion hereof will be issued in the name of the Holder hereof upon the
cancellation hereof.

         The Indenture contains provisions for defeasance at any time of the
entire indebtedness of this Security or certain restrictive covenants and Events
of Default with respect to this Security, in each case upon compliance with
certain conditions set forth in the Indenture.

         If an Event of Default with respect to Securities of this series shall
occur and be continuing, the principal of the Securities of this series may be
declared due and payable in the manner and with the effect provided in the
Indenture.

         The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of a majority in principal amount of the Securities at
the time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in principal amount
of the Securities of each series at the time Outstanding, on behalf of the
Holders of all Securities of such series, to waive compliance by the Company
with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences. Any such consent or waiver by the Holder of
this Security shall be conclusive and binding upon such Holder and upon all
future Holders of this Security and of any Security issued upon the registration
of transfer hereof or in

                                      -5-

<PAGE>

exchange herefor or in lieu hereof, whether or not notation of such consent or
waiver is made upon this Security.

         As provided in and subject to the provisions of the Indenture, the
Holder of this Security shall not have the right to institute any proceeding
with respect to the Indenture or for the appointment of a receiver or trustee or
for any other remedy thereunder, unless such Holder shall have previously given
the Trustee written notice of a continuing Event of Default with respect to the
Securities of this series, the Holders of not less than 25% in principal amount
of the Securities of this series at the time Outstanding shall have made written
request to the Trustee to institute proceedings in respect of such Event of
Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee
shall not have received from the Holders of a majority in principal amount of
Securities of this series at the time Outstanding a direction inconsistent with
such request, and shall have failed to institute any such proceeding, for 60
days after receipt of such notice, request and offer of indemnity. The foregoing
shall not apply to any suit instituted by the Holder of this Security for the
enforcement of any payment of principal hereof or any premium or interest hereon
on or after the respective due dates expressed herein.

         No reference herein to the Indenture and no provision of this Security
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of and any premium and
interest on this Security at the times, place and rate, and in the coin or
currency, herein prescribed.

         As provided in and subject to the provisions of the Indenture, a
director, officer, employee, incorporator or stockholder, as such, of the
Company shall not have any liability for any obligations of the Company under
this Security or the Indenture. By accepting this Security, each Holder shall
waive and release all such liability. The waiver and release shall be part of
the consideration for the issue of the Securities.

         As provided in the Indenture and subject to certain limitations therein
set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for registration of transfer at the
office or agency of the Company in any place where the principal of and any
premium and interest on this Security are payable, duly endorsed by, or
accompanied by a written instrument of transfer in form satisfactory to the
Company and the Security Registrar duly executed by, the Holder hereof or his
attorney duly authorized in writing, and thereupon one or more new Securities of
this series and of like tenor, of authorized denominations and for the same
aggregate principal amount, will be issued to the designated transferee or
transferees.

         The Securities of this series are issuable only in registered form
without coupons in denominations of $1,000 and any integral multiple thereof. As

                                      -6-

<PAGE>

provided in the Indenture and subject to certain limitations therein set forth,
Securities of this series are exchangeable for a like aggregate principal amount
of Securities of this series and of like tenor of a different authorized
denomination, as requested by the Holder surrendering the same.

         No service charge shall be made for any such registration of transfer
or exchange, but the Company may require payment of a sum sufficient to cover
any tax or other governmental charge payable in connection therewith.

         Prior to due presentment of this Security for registration of transfer,
the Company, the Trustee and any agent of the Company or the Trustee may treat
the Person in whose name this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

         All terms used in this Security which are defined in the Indenture
shall have the meanings assigned to them in the Indenture.

                                      -7-