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                                                                     EXHIBIT 3.1

                           CERTIFICATE OF DESIGNATION,
                            PREFERENCES AND RIGHTS OF
                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK
                                       OF
                          ACCREDO HEALTH, INCORPORATED

                         Pursuant to Section 151 of the
                        Delaware General Corporation Law


         Accredo Health, Incorporated, a corporation organized under the laws of
the State of Delaware (the "Corporation"), hereby certifies that, pursuant to
the authority conferred upon the Board of Directors by the Certificate of
Incorporation, as amended, of the Corporation, the Board of Directors on April
17, 2003, adopted the following resolution creating a series of 100,000 shares
of Preferred Stock designated as Series A Junior Participating Preferred Stock:

         RESOLVED, that pursuant to the authority granted to and vested in the
Board of Directors of this Corporation (the "Board") in accordance with the
provisions of its Certificate of Incorporation, as amended, a series of
Preferred Stock of the Corporation be and it hereby is created, and that the
designation and amount thereof and the voting rights or powers, preferences and
relative, participating, optional and other special rights of the shares of such
series, and the qualifications, limitations or restrictions thereof are as
follows:

         1. Series A Junior Participating Preferred Stock. There is hereby
established a series of Preferred Stock, par value $1.00 per share, of the
Corporation, and the designation and certain terms, powers, preferences and
other rights of the shares of such series, and certain qualifications,
limitations and restrictions thereon, are hereby fixed as follows:

             (i) The distinctive serial designation of this series shall be
"Series A Junior Participating Preferred Stock" (hereinafter called "this
Series"). Each share of this Series shall be identical in all respects with the
other shares of this Series except as to the dates from and after which
dividends thereon shall be cumulative.

             (ii) The number of shares in this Series shall initially be
100,000, which number may from time to time be increased or decreased (but not
below the number then outstanding) by the Board of Directors. Shares of this
Series purchased by the Corporation shall be canceled and shall revert to
authorized but unissued shares of Preferred Stock undesignated as to series.
Shares of this Series may be issued in fractional shares, which fractional
shares shall entitle the holder, in proportion to such holder's fractional
share, to all rights of a holder of a whole share of this Series.

             (iii) The holders of full or fractional shares of this Series shall
be entitled to receive, when and as declared by the Board of Directors, but only
out of funds legally available therefor, dividends, (A) on each date that
dividends or other distributions (other



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than dividends or distributions payable in Common Stock of the Corporation) are
payable on or in respect of Common Stock comprising part of the Reference
Package (as defined below), in an amount per whole share of this Series equal to
the aggregate amount of dividends or other distributions (other than dividends
or distributions payable in Common Stock of the Corporation) that would be
payable on such date to a holder of the Reference Package and (B) on the last
day of March, June, September and December in each year, in an amount per whole
share of this Series equal to the excess (if any) of $1.00 over the aggregate
dividends paid per whole share of this Series during the three-month period
ending on such last day. Each such dividend shall be paid to the holders of
record of shares of this Series on the date, not exceeding 60 days preceding
such dividend or distribution payment date, fixed for that purpose by the Board
of Directors in advance of payment of each particular dividend or distribution.
Dividends on each full and each fractional share of this Series shall be
cumulative from the date such full or fractional share is originally issued;
provided that any such full or fractional share originally issued after a
dividend record date and on or prior to the dividend payment date to which such
record date relates shall not be entitled to receive the dividend payable on
such dividend payment date or any amount in respect of the period from such
original issuance to such dividend payment date.

             The term "Reference Package" shall initially mean 10,000 shares of
Common Stock, par value $.01 per share ("Common Stock"), of the Corporation. In
the event the Corporation shall at any time (A) declare or pay a dividend on any
Common Stock payable in Common Stock, (B) subdivide any Common Stock or (C)
combine any Common Stock into a smaller number of shares, then and in each such
case the Reference Package after such event shall be the Common Stock that a
holder of the Reference Package immediately prior to such event would hold
thereafter as a result thereof.

             Holders of shares of this Series shall not be entitled to any
dividends, whether payable in cash, property or stock, in excess of full
cumulative dividends, as herein provided, on this Series.

             So long as any shares of this Series are outstanding, no dividend
(other than a dividend in Common Stock or in any other stock ranking junior to
this Series as to dividends and upon liquidation) shall be declared or paid or
set aside for payment or other distribution declared or made upon the Common
Stock or upon any other stock ranking junior to this Series as to dividends or
upon liquidation, nor shall any Common Stock nor any other stock of the
Corporation ranking junior to or on a parity with this Series as to dividends or
upon liquidation be redeemed, purchased or otherwise acquired for any
consideration (or any moneys be paid to or made available for a sinking fund for
the redemption of any shares of any such stock) by the Corporation (except by
conversion into or exchange for stock of the Corporation ranking junior to this
Series as to dividends and upon liquidation), unless, in each case, the full
cumulative dividends (including the dividend to be due upon payment of such
dividend, distribution, redemption, purchase or other acquisition) on all
outstanding shares of this Series shall have been, or shall contemporaneously
be, paid.



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             (iv) In the event of any merger, consolidation, reclassification or
other transaction in which the shares of Common Stock are exchanged for or
changed into other stock or securities, cash and/or any other property, then in
any such case the shares of this Series shall at the same time be similarly
exchanged or changed in an amount per whole share equal to the aggregate amount
of stock, securities, cash and/or any other property (payable in kind), as the
case may be, that a holder of the Reference Package would be entitled to receive
as a result of such transaction.

             (v) In the event of any liquidation, dissolution or winding up of
the affairs of the Corporation, whether voluntary or involuntary, the holders of
full and fractional shares of this Series shall be entitled, before any
distribution or payment is made on any date to the holders of the Common Stock
or any other stock of the Corporation ranking junior to this Series upon
liquidation, to be paid in full an amount per whole share of this Series equal
to the greater of (A) $1.00 or (B) the aggregate amount distributed or to be
distributed prior to such date in connection with such liquidation, dissolution
or winding up to a holder of the Reference Package (such greater amount being
hereinafter referred to as the "Liquidation Preference"), together with accrued
dividends to such distribution or payment date, whether or not earned or
declared. If such payment shall have been made in full to all holders of shares
of this Series, the holders of shares of this Series as such shall have no right
or claim to any of the remaining assets of the Corporation.

             In the event the assets of the Corporation available for
distribution to the holders of shares of this Series upon any liquidation,
dissolution or winding up of the Corporation, whether voluntary or involuntary,
shall be insufficient to pay in full all amounts to which such holders are
entitled pursuant to the first paragraph of this Section (v), no such
distribution shall be made on account of any shares of any other class or series
of Preferred Stock ranking on a parity with the shares of this Series upon such
liquidation, dissolution or winding up unless proportionate distributive amounts
shall be paid on account of the shares of this Series, ratably in proportion to
the full distributable, amounts for which holders of all such parity shares are
respectively entitled upon such liquidation, dissolution or winding up.

             Upon the liquidation, dissolution or winding up of the Corporation,
the holders of shares of this Series then outstanding shall be entitled to be
paid out of assets of the Corporation available for distribution to its
stockholders all amounts to which such holders are entitled pursuant to the
first paragraph of this Section (v) before any payment shall be made to the
holders of Common Stock or any other stock of the Corporation ranking junior
upon liquidation to this Series.

             For the purposes of this Section (v), the consolidation or merger
of, or binding share exchange by, the Corporation with any other corporation
shall not be deemed to constitute a liquidation, dissolution or winding up of
the corporation.

             (vi) The shares of this Series shall not be redeemable.


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             (vii) In addition to any other vote or consent of stockholders
required by law or by the Certificate of Incorporation of the Corporation, each
whole share of this Series shall, on any matter, vote as a class with any other
capital stock comprising part of the Reference Package and voting on such matter
and shall have the number of votes thereon that a holder of the Reference
Package would have.

         IN WITNESS WHEREOF, Accredo Health, Incorporated has caused this
Certificate of Designation to be executed as of April 25, 2003.


                                        ACCREDO HEALTH, INCORPORATION




                                        By: /s/ Thomas W. Bell, Jr.
                                           -------------------------------------
                                        Name:  Thomas W. Bell, Jr.
                                        Title: Senior Vice President and
                                               General Counsel