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                                                                     EXHIBIT 3.1
 
                             ARTICLES OF AMENDMENT
                OF THE ARTICLES OF INCORPORATION OF IOMED, INC.
 
     Pursuant to the provisions of the provisions of the Utah Revised Business
Corporation Act (the "Act"), the undersigned corporation adopts the following
Articles of Amendment to its Articles of Incorporation:
 
     FIRST: The name of the corporation is IOMED, Inc.
 
     SECOND: Article II of the corporation's Articles of Incorporation is hereby
amended by adding thereto a new paragraph D, which shall read in its entirety as
set forth on Exhibit "A" to these Articles of Amendment, which by this reference
is incorporated herein as though set forth herein in full.
 
     THIRD: The foregoing amendment to the corporation's Articles of
Incorporation do not provide for an exchange, reclassification or cancellation
of issued shares of the corporation.
 
     FOURTH: Pursuant to the Act, the foregoing amendment to the corporation's
Articles of Incorporation was adopted by the Board of Directors of the
corporation on the 28th day of April, 1998.
 
     FIFTH: Pursuant to the Act, the foregoing amendment to the corporation's
Articles of Incorporation was adopted by the Board of Directors of the
corporation without shareholder action, and no such shareholder action was
required under the Act or the corporation's Articles of Incorporation.
 
     IN WITNESS WHEREOF, the undersigned has executed these Articles of
Amendment as of this 28th day of April, 1998.
 
                                          IOMED, INC.
 
                                          By:      /s/ ROBERT J. LOLLINI
                                               Robert J. Lollini
                                               Vice President and Chief
                                                   Financial Officer
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                                   EXHIBIT A
 
     "D. SERIES D NON-VOTING PREFERRED SHARES.  A total of 1,000,000 Preferred
     Shares shall be designated as "Series D Non-Voting Preferred Shares", and
     shall have the following preferences, limitations and relative rights:
 
     1. VOTING RIGHTS.  Except as otherwise expressly provided by law, the
holders of Series D Non-Voting Preferred Shares shall not have the right to vote
upon matters submitted to the shareholders of the corporation for consideration
and vote; provided, however, that such holders shall be entitled to notice of
any shareholders' meeting in accordance with the Bylaws of the Corporation.
 
     2. LIQUIDATION RIGHTS.  The Series D Non-Voting Preferred Shares shall not
have any liquidation or similar preference over the Common Stock in the event of
any voluntary or involuntary liquidation, dissolution or winding up of the
affairs of the Corporation. Upon any such liquidation, dissolution or winding
up, and after payment or provision for payment of the debt and other liabilities
of the Corporation, the holders of Series D Non-Voting Preferred Shares then
outstanding shall be entitled to receive, for each Common Share into which a
Series D Non-Voting Preferred Share is then convertible, the same amounts, if
any, as are received by the holders of Common Shares as the result of or in
connection with such liquidation, dissolution or winding up.
 
     3. DIVIDENDS.  The holders of shares of Series D Non-Voting Preferred
Shares shall be entitled, when and if declared by the Board of Directors, to
receive dividends and distributions out of any assets legally available
therefor. No dividend or distribution of cash, securities of other persons,
assets, or options or rights (not referred to in section 4(c) hereof) may be
declared or paid on the Common Shares unless at the same time an equivalent
dividend or distribution, as the case may be, is declared or paid on all
outstanding Series D Non-Voting Preferred Shares. No dividend or distribution of
cash, securities of other persons, assets or options or rights (not referred to
Section 4(c) hereof) may be declared or paid on the Series D Non-Voting
Preferred Shares unless at the same time an equivalent dividend or distribution,
as the case may be, is declared or paid on all outstanding Common Shares. In the
event a dividend or distribution is declared on the Common Shares, the dividend
or distribution on each Series D Non-Voting Preferred Share shall be paid at the
same rate per share based upon the number of Common Shares into which such share
of Series D Non-Voting Preferred Shares is convertible immediately prior to the
record date for such dividend or distribution. The right to dividends or
distributions on Series D Non-Voting Preferred Shares shall not be cumulative,
and no right shall accrue to holders of Series D Non-Voting Preferred Shares by
reason of the fact that dividends on said shares are not declared in any period.
 
     4. CONVERSION.  The holders of Series D Non-Voting Preferred Shares shall
have conversion rights as follows (the "Conversion Rights"):
 
          (a) Conversion. Subject to the adjustments set forth in subsection (c)
     below, each Series D Non-Voting Preferred Share shall be convertible, at
     the option of the holder thereof and at any time after the date of issuance
     of such share, at the office of the corporation or any transfer agent for
     the Series D Non-Voting Preferred Shares, into one fully paid and
     non-assessable Common Share (the "Conversion Rate").
 
          (b) Mechanics of Conversion. Before any holder of the Series D
     Non-Voting Preferred Shares shall be entitled to convert the same into
     Common Shares, such holder shall surrender the certificate or certificates
     therefor, duly endorsed, at the office of the Corporation or of any
     transfer agent for the Series D Non-Voting Preferred Shares, and shall give
     written notice by mail, postage prepaid, to the Corporation at its
     principal corporate office. The written notice shall state the holder's
     election to convert Series D Non-Voting Preferred Shares and shall state
     therein the name or names in which the certificate or certificates for
     Common Shares are to be issued. The Corporation shall, as soon as
     practicable thereafter, issue, or cause to be issued, and deliver at such
     office to such holder, or to the nominee or nominees of such holder, a
     certificate or certificates for the number of Common Shares to which such
     holder shall be entitled. Such conversion shall be deemed to have been made
     immediately prior to the close of business on the date of the surrender of
     the shares to be converted, and the person or persons
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     entitled to receive the Common Shares issuable upon such conversion shall
     be treated for all purposes as the record holder or holders of such Common
     Shares as of such date.
 
          (c) Adjustment Upon Split, Subdivision, Etc.
 
             (i) In the event the Corporation should, at any time or from time
        to time after the date on which any Series D Non-Voting Preferred Shares
        are issued, fix a record date for the effectuation of a split or
        subdivision of the outstanding Common Shares or the determination of
        holders of Common Shares entitled to receive a dividend or other
        distribution payable in additional Common Shares or in other securities
        or rights convertible or exercisable into, or exchangeable for,
        additional Common Shares (such other securities or rights hereinafter
        referred to as "Common Share Equivalents") without payment of any
        consideration by such holder for the additional Common Shares or the
        Common Share Equivalents (including the additional Common Shares
        issuable upon conversion, exercise or exchange thereof), then, as of
        such record date (or the date of such dividend, distribution, split or
        subdivision if no record date is fixed), the Conversion Rate of the
        Series D Non-Voting Preferred Shares shall be appropriately adjusted so
        that the number of Common Shares issuable on conversion of each Series D
        Non-Voting Preferred Share shall be increased in proportion to such
        increase of outstanding Common Shares (including Common Shares
        represented by Common Share Equivalents in the manner of (ii) below).
 
             (ii) In the case of a dividend or other distribution payable in
        Common Share Equivalents, the following provisions shall apply for
        purposes of subparagraph (c)(i):
 
                A. The aggregate maximum number of Common Shares deliverable
           upon the conversion or exercise of, or in exchange for, such Common
           Share Equivalents shall be deemed to have been issued and to be
           outstanding as of the record date therefor (or the date of such
           dividend or distribution if no record date is fixed), but no further
           adjustment shall be made for the actual issuance of Common Shares
           upon the conversion, exercise or exchange of such Common Share
           Equivalents.
 
                B. In the event of any change in the number of Common Shares
           deliverable upon the conversion or exercise of, or in exchange for,
           such Common Share Equivalents, including without limitation a change
           resulting from the antidilution provisions thereof, the Conversion
           Rate then in effect for the Series D Non-Voting Preferred Shares
           shall forthwith be readjusted to such Conversion Rate as would have
           been obtained had the adjustment which was made in connection with
           such Common Share Equivalents which were not converted, exercised or
           exchanged prior to such change been made upon the basis of such
           change, but no further adjustment shall be made for the actual
           issuance of Common Shares upon the conversion, exercise or exchange
           of such Common Share Equivalents.
 
                C. Upon the expiration or termination of any Common Share
           Equivalents, the Conversion Rate for the Series D Non-Voting
           Preferred Shares shall forthwith be readjusted to such Conversion
           Rate as would have been obtained had the adjustment which was made in
           connection with such Common Share Equivalents been made upon the
           basis of the issuance of only the number of Common Shares actually
           issued upon the conversion, exercise or exchange of such Common Share
           Equivalents.
 
             (iii) If the number of Common Shares outstanding at any time after
        the date on which any Series D Non-Voting Preferred Shares are issued is
        decreased by a combination of the outstanding Common Shares, then,
        following the record date of such combination, the Conversion Rate for
        the Series D Non-Voting Preferred Shares shall be appropriately
        decreased in proportion to such decrease in outstanding shares.
 
          (d) Recapitalizations.  If at any time or from time to time there
     shall be a recapitalization of the Common Shares (other than a subdivision,
     combination or merger or sale of assets transaction provided for elsewhere
     in this Section 4), provision shall be made so that the holders of the
     Series D Non-Voting Preferred Shares shall thereafter be entitled to
     receive, with respect to each Common Share acquired
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     upon conversion of the Series D Non-Voting Preferred Shares, the number of
     shares of stock or other securities or property of the Corporation or
     otherwise, to which a holder of Common Shares would have been entitled on
     such recapitalization. In any such case, appropriate adjustment shall be
     made in the application of the provisions of this Section 4 with respect to
     the rights of the holders of the Series D Non-Voting Preferred Shares after
     the recapitalization to the end that the provisions of this Section 4 shall
     be applicable after the recapitalization in a manner which is, as nearly
     equivalent as may be practicable, equivalent to the manner in which this
     Section 4 applied prior to the recapitalization.
 
          (e) No Impairment.  The Corporation will not, by amendment of its
     Articles of Incorporation or Bylaws or through any reorganization,
     recapitalization, transfer of assets, consolidation, merger, dissolution,
     issuance or sale of securities, agreement or any other voluntary action,
     avoid or seek to avoid the observance or performance by the Corporation of
     its obligations hereunder, but will, at all times and in good faith, take
     such actions as may be necessary to carry out the intent of the provisions
     of this Section 4.
 
          (f) No Fractional Shares and Certificates as to Adjustments.
 
             (i) No fractional shares shall be issued upon conversion of the
        Series D Non-Voting Preferred Shares, and the number of Common Shares to
        be issued shall be rounded to the nearest whole share, determined on the
        basis of the total number of Series D Non-Voting Preferred Shares which
        the holder is at the time converting into Common Shares and the number
        of Common Shares issuable upon such aggregate conversion.
 
             (ii) Upon the occurrence of each adjustment or readjustment of the
        Conversion Rate of the Series D Non-Voting Preferred Shares pursuant to
        this Section 4, the Corporation, at its expense, shall promptly compute
        such adjustment or readjustment in accordance with he terms hereof and
        prepare and furnish to each holder of Series D Non-Voting Preferred
        Shares a certificate setting forth such adjustment or readjustment and
        showing in detail the facts upon which such adjustment or readjustment
        is based. The Corporation shall, upon the written request of any holder
        of Series D Non-Voting Preferred Shares, furnish or cause to be
        furnished to such holder a like certificate setting forth (A) such
        adjustment and readjustment, (B) the Conversion Rate at the time in
        effect, and (C) the number of Common Shares and the amount, if any, of
        other property which at the time would be received upon the conversion
        of a Series D Non-Voting Preferred Share.
 
          (g) Notice of Record Date.  In the event of any taking by the
     Corporation of a record of the holders of any class of securities for the
     purpose of determining the holders thereof who are entitled to receive any
     dividend (other than a cash dividend) or other distribution, any right to
     subscribe for, purchase or otherwise acquire any shares of any class or any
     other securities of property, or to receive any other right, the
     Corporation shall mail to each holder of Series D Non-Voting Preferred
     Shares, at least 10 days prior to the date specified therein, a notice
     specifying the date on which any such record is to be taken for the purpose
     of such dividend, distribution or right, and the amount and character of
     such dividend, distribution or right.
 
          (h) Reservation of Common Shares Issuable Upon Conversion.  The
     Corporation shall at all times reserve and keep available out of its
     authorized but unissued Common Shares, solely for the purpose of effecting
     the conversion of the Series D Non-Voting Preferred Shares, such number of
     its Common Shares as shall from time to time be sufficient to effect the
     conversion of all outstanding Series D Non-Voting Preferred Shares. If at
     any time the number of authorized but unissued Common Shares shall not be
     sufficient to effect the conversion of all then outstanding Series D
     Non-Voting Preferred Shares, the Corporation will take such corporate
     action as may, in the opinion of its counsel, be necessary to increase its
     authorized but unissued Common Shares to such number of shares as shall be
     sufficient for such purposes.
 
          (i) Notices.  Any notice required by the provisions of this Section 4
     to be given to the holders of Series D Non-Voting Preferred Shares shall be
     deemed given if deposited in the United States mail, postage prepaid, and
     addressed to each holder of record at his, her or its address, as such
     address then appears on the books of the Corporation."
 
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