SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549
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                        SCHEDULE 13D/A4 (Amendment No. 4)
          Under the Securities Exchange Act of 1934 (Amendment No. 4)*

                                   IOMED, INC.
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                                (Name of Issuer)

                     Common Stock, par value $0.01 per share
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                         (Title of Class of Securities)

                                    462028101
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                                 (CUSIP Number)

                                William F. Daniel
                              Elan Corporation, plc
                                Treasury Building
                            Lower Grand Canal Street
                                Dublin 2, Ireland
                                (353) 1-709-4000

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            (Name, Address and Telephone Number of Person Authorized
                     to Receive Notices and Communications)


                                 March 31, 2005
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             (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of ss.ss. 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the
following box [ ].

NOTE: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 240.13d-7 for other
parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).




                                  Page 1 of 8





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CUSIP No.  45325S-10-1
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       (1)         NAME OF REPORTING PERSONS
                   Elan Corporation, plc

                   I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only)
                   N/A
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       (2)         CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See
                   Instructions) 
                   (a) [ ]
                   (b)  [  ]
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       (3)         SEC USE ONLY

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       (4)         SOURCE OF FUNDS (See Instructions)
                   WC, OO
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       (5)         CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
                   PURSUANT TO ITEMS 2(d) or 2(e)  [  ]
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       (6)         CITIZENSHIP OR PLACE OF ORGANIZATION
                   Ireland
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    Number of      (7)     SOLE VOTING POWER
     Shares                -0-  (See Item 5)
                   -------------------------------------------------------------
  Beneficially     (8)     SHARED VOTING POWER
      Owned                -0-  (See Item 5)
                   -------------------------------------------------------------
     by Each       (9)     SOLE DISPOSITIVE POWER
    Reporting              -0-  (See Item 5)
                   -------------------------------------------------------------
   Person With     (10)    SHARED DISPOSITIVE POWER
                           -0-  (See Item 5)
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      (11)         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                   -0- (See Item 5)
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      (12)         CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES 
                   CERTAIN SHARES (See Instructions)  [  ]
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      (13)         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% (See
                   Item 5)
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      (14)         TYPE OF REPORTING PERSON (See Instructions) CO
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                                  Page 2 of 8





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CUSIP No.  45325S-10-1
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       (1)          NAME OF REPORTING PERSONS Elan International Services, Ltd.

                    I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only)
                    N/A
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       (2)          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP 
                    (See Instructions)
                    (a) [ ] 
                    (b) [ ]
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       (3)          SEC USE ONLY

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       (4)          SOURCE OF FUNDS (See Instructions)
                    WC, OO
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       (5)          CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
                    PURSUANT TO ITEMS 2(d) or 2(e)  [  ]
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       (6)          CITIZENSHIP OR PLACE OF ORGANIZATION
                    Bermuda
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    Number of       (7)     SOLE VOTING POWER
      Shares                -0-  (See Item 5)
                    ------------------------------------------------------------
Beneficially Owned  (8)     SHARED VOTING POWER
                            -0-  (See Item 5)
                    ------------------------------------------------------------
     by Each        (9)     SOLE DISPOSITIVE POWER
    Reporting               -0-  (See Item 5)
                    ------------------------------------------------------------
   Person With      (10)    SHARED DISPOSITIVE POWER
                            -0-  (See Item 5)
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       (11)         AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                    -0- (See Item 5)
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       (12)         CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
                    SHARES (See Instructions)  [  ]
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       (13)         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% (See
                    Item 5)
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       (14)         TYPE OF REPORTING PERSON (See Instructions) CO
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Item 1. Security and Issuer.

     Item 1 of the Schedule 13D is hereby amended and restated in its entirety
as follows:

     This Amendment No. 4 is filed by Elan Corporation, plc, an Irish public
limited company ("Elan"), and Elan's direct wholly-owned subsidiary, Elan
International Services, Ltd., a Bermuda exempted company ("EIS"), and relates to
the common stock, par value $.01 per share (the "Common Stock"), of Iomed, Inc.,
a Delaware corporation ("Issuer"). This Amendment No. 4 amends the Schedule 13D
filed with the Securities and Exchange Commission (the "Commission") on May 19,
1998, as amended by the Amendment No. 1 to Schedule 13D filed with the
Commission on June 25, 2004 by Elan and EIS, the Amendment No. 2 to Schedule 13D
filed with the Commission on July 16, 2004 by Elan and EIS and the Amendment No.
3 to Schedule 13D filed with the Commission on December 28, 2004 by Elan and EIS
(the "Schedule 13D"). The name and address of the principal executive offices of
the Issuer is Iomed, Inc., 3385 West 1820 South, Salt Lake City, Utah 84104.

Item 2. Identity and Background.

     Item 2 of the Schedule 13D is hereby amended and restated in its entirety
as follows:

     This Schedule 13D is filed by Elan and EIS, in respect of Common Stock that
was beneficially owned directly by EIS.

     Elan's principal place of business is Treasury Building, Lower Grand Canal
Street, Dublin 2, Ireland. Elan is a worldwide biopharmaceutical company. EIS's
principal place of business is 102 St. James Court, Flatts, Smiths, FL 04
Bermuda. EIS is an investment holding company.

     Schedule A to this Schedule 13D sets forth the (a) name, (b) residence or
business address, (c) present principal occupation or employment and the name,
principal business and address of any corporation or other organization in which
such employment is conducted and (d) citizenship or place of organization of
each executive officer, director and controlling person of Elan and EIS.

     Except as set forth below, during the last five years, neither Elan or EIS
nor, to their knowledge, any person identified on Schedule A to this Schedule
13D: (i) has been convicted in a criminal proceeding (excluding traffic
violations or similar misdemeanors); or (ii) was a party to a civil proceeding
of a judicial or administrative body of competent jurisdiction, as a result of
which proceeding it was or is subject to a judgment, decree or final order
enjoining future violations of, or prohibiting or mandating activities subject
to, United States federal or state securities laws, or finding any violation
with respect to such laws.

     On February 8, 2005, the Securities and Exchange Commission (the "SEC")
filed a civil action against Elan in the United States District Court for the
District of Columbia (the "Court") (Civil Action No. 05-282). In the complaint,
the SEC alleged that Elan violated the antifraud provisions of the federal
securities laws for failing to disclose material information about Elan's
financial results in periodic reports filed with the SEC and in quarterly
earnings press releases disseminated to investors. Without admitting or denying
the allegations in the action, Elan consented to the entry of a final judgment
that permanently enjoins Elan from violating the antifraud provisions of the
federal securities laws, Section 10(b) of the Securities Exchange Act of 1934
(the "Exchange Act") and Rule 10b-5 thereunder, as well as reporting and
internal control provisions, Sections 13(a) and 13(b)(2)(B) of the Exchange Act
and Rules 12b-20, 13a-1 and 13a-16 thereunder. The judgment ordered Elan to pay
$1 in disgorgement and a $15 million civil penalty. The final judgment was
entered by the Court on February 10, 2005.



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Item 4. Purpose of Transaction.

     The fifth paragraph of Item 4 of the Schedule 13D is hereby amended by
adding the following at the end:

By letter dated January 16, 2003, EIS notified the Issuer that the individual
EIS had previously designated to serve on the Issuer's Board of Directors should
no longer be considered EIS's designee and that EIS reserved the right to
designate a new EIS designee to the Board. EIS never exercised its right to
designate a different director and, by letter dated December 23, 2004, EIS
renounced its right to designate a director to serve on the Issuer's Board of
Directors.

Item 5. Interest in Securities of Issuer.

     Item 5 of the Schedule 13D is hereby amended and restated in its entirety
as follows:

     (a) None.

     (b) None.

     (c) On March 31, 2005, EIS sold an aggregate of 854,291 shares of Common
Stock in open market transactions for a price per share of $1.70.

     (d) Not applicable.

     (e) EIS ceased to be the beneficial owner of more than five percent of the
Common Stock on March 31, 2005.




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                                   SIGNATURES

     After reasonable inquiry and to the best of its knowledge and belief, each
of the undersigned certifies that the information set forth in this statement is
true, complete and correct.

Date:  April 29, 2005


                                ELAN CORPORATION, PLC





                                By:    /s/ William F. Daniel
                                       ------------------------------------
                                       Name:   William F. Daniel
                                       Title:  EVP and Company Secretary



                                ELAN INTERNATIONAL SERVICES, LTD.





                                By:    /s/ Kevin Insley
                                       ------------------------------------
                                       Name:   Kevin Insley
                                       Title:  President






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                                   SCHEDULE A

The (a) name, (b) business address, (c) present principal occupation or
employment and the name, principal business and address of any corporation or
other organization in which such employment is conducted and (d) citizenship of
each executive officer and director (other than Messrs. Armen, Boushel, Crowley,
Gillespie, Groom, McGowan, McIntyre, McLaughlin, Selkoe and Thornburgh and Ms.
Gray) of Elan are set forth below:

1.   (a) G. Kelly Martin, (b) 875 Third Avenue, New York, New York 10022, (c)
     President and Chief Executive Officer, and (d) United States.

2.   (a) Shane Cooke, (b) Treasury Building, Lower Grand Canal Street, Dublin 2,
     Ireland, (c) Executive Vice President and Chief Financial Officer, and (d)
     Ireland.

3.   (a) William F. Daniel (b) Treasury Building, Lower Grand Canal Street,
     Dublin 2, Ireland, (c) Executive Vice President and Company Secretary, and
     (d) Ireland.

4.   (a) Richard Collier, (b) 3500 Horizon Drive, King of Prussia, PA 19406, (c)
     Executive Vice President and General Counsel, and (d) United States.

5.   (a) Paul Breen, (b) Treasury Building, Lower Grand Canal Street, Dublin 2,
     Ireland, (c) Executive Vice President, Global Services and Operations, and
     (d) Ireland.

The (a) name, (b) business address, (c) present principal occupation or
employment and the name, principal business and address of any corporation or
other organization in which such employment is conducted and (d) citizenship of
each director (other than Messrs. Martin and Daniel) of Elan are set forth
below:

1.   (a) Garo A. Armen, Ph.D., (b) 630 Fifth Avenue, Suite 2167, New York, New
     York 10111, (c) Chairman of the Board and Chief Executive Officer of
     Antigenics, Inc., and (d) United States.

2.   (a) Brendan E. Boushel, (b) 9 Upper Mount Street, Dublin 2, Ireland, (c)
     Retired, and (d) Ireland.

3.   (a) Laurence G. Crowley, (b) c/o Elan Corporation, plc, Treasury Building,
     Lower Grand Canal Street, Dublin 2, Ireland, (c) Governor (Chairman) Bank
     of Ireland, and (d) Ireland.

4.   (a) Alan R. Gillespie, Ph.D., (b) c/o Elan Corporation, plc, Treasury
     Building, Lower Grand Canal Street, Dublin 2, Ireland, (c) Chairman, Ulster
     Bank Limited, and (d) United Kingdom.

5.   (a) Ann Maynard Gray, (b) c/o Elan Corporation, plc, Treasury Building,
     Lower Grand Canal Street, Dublin 2, Ireland, (c) Retired, and (d) United
     Kingdom.

6.   (a) John Groom, (b) c/o Elan Corporation, plc, Treasury Building, Lower
     Grand Canal Street, Dublin 2, Ireland, (c) Retired, and (d) United Kingdom.

7.   (a) Kieran McGowan, (b) c/o Elan Corporation, plc, Treasury Building, Lower
     Grand Canal Street, Dublin 2, Ireland, (c) Retired, and (d) Ireland.

8.   (a) Kevin M. McIntyre, M.D., (b) c/o Elan Corporation, plc, Treasury
     Building, Lower Grand Canal Street, Dublin 2, Ireland, (c) Associate
     Clinical Professor of Medicine at Harvard Medical 



                                  Page 7 of 8


     School, and (d) United States.

9.   (a) Kyran McLaughlin, (b) Davy House, 49 Dawson Street, Dublin 2, Ireland,
     (c) Head of Equities and Corporate Finance, Davy Stockbrokers, and (d)
     Ireland.

10.  (a) Dennis J. Selkoe, M.D., (b) c/o Elan Corporation, plc, Treasury
     Building, Lower Grand Canal Street, Dublin 2, Ireland, (c) Professor of
     Neurology and Neuroscience at Harvard Medical School, and (d) United
     States.

11.  (a) Richard L. Thornburgh, (b) c/o Elan Corporation, plc, Treasury
     Building, Lower Grand Canal Street, Dublin 2, Ireland, (c) Counsel to the
     law firm of Kirkpatrick & Lockhart LLP, and (d) United States.

The (a) name, (b) business address, (c) present principal occupation or
employment and the name, principal business and address of any corporation or
other organization in which such employment is conducted and (d) citizenship of
each executive officer and director of EIS are set forth below:

1.   (a) Kevin Insley, (b) c/o 102 St. James Court, Flatts, Smiths FL 04,
     Bermuda, (c) Director, President and Chief Financial Officer, and (d)
     United Kingdom.

2.   (a) Debra Moore Buryj, (b) c/o 102 St. James Court, Flatts, Smiths FL 04,
     Bermuda, (c) Director and Vice President and, (d) United States.

3.   (a) David J. Doyle, (b) c/o Clarendon House, 2 Church Street, Hamilton HM
     11, Bermuda, (c) Director of EIS, and principal occupation is lawyer, law
     firm of Conyers, Dill & Pearman, Clarendon House, 2 Church Street, Hamilton
     HM 11, Bermuda, and (d) Bermuda.




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