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                                UNITED STATES
                     SECURITIES AND EXCHANGE COMMISSION
                           WASHINGTON, D.C. 20549

                                SCHEDULE 13D

                  UNDER THE SECURITIES EXCHANGE ACT OF 1934

                            (AMENDMENT NO. 6 )*
                                          ---
                                 Akorn, Inc.
- -------------------------------------------------------------------------------
                              (Name of Issuer)

                          Common Stock, no par value
- -------------------------------------------------------------------------------
                       (Title of Class of Securities)

                                 009728 10 6
                       ------------------------------
                               (CUSIP Number)


John N. Kapoor                     Copy to:  Christopher R. Manning
EJ Financial Enterprises, Inc.               Burke, Warren, MacKay
225 E. Deerpath, Suite 250                      & Serritella, P.C.
Lake Forest, IL 60045                        330 N. Wabash, 22nd Floor
                                             Chicago, IL 60611
- -------------------------------------------------------------------------------
                (Name, Address and Telephone Number of Person
              Authorized to Receive Notices and Communications)

                              December 30, 1997
                      ---------------------------------
                    (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 which is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(b)(3) or (4), check the following box /  /.

Check the following box if a fee is being paid with the statement  /  /.  (A
fee is not required only if the reporting person:  (1) has a previous statement
on file reporting beneficial ownership of more than five percent of the class
of securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such class.)
(See Rule 13d-7).

Note:  Six copies of this statement, including all exhibits, should be filed
with the Commission.  See Rule 13d-1(a) for other parties to whom copies are to
be sent.

*The remainder of this cover page shall be filed 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).

                      (Continued on following page(s))

                            Page  1  of  8  Pages
                                 ---    ---
     

<PAGE>   2

                                 SCHEDULE 13D

CUSIP NO.   009728 10 6                                   PAGE  2  OF  8  PAGES
           ----------------                                    ----   ----
===============================================================================
1    NAME OF REPORTING PERSON
     S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     John N. Kapoor Trust, dated September 20, 1989

- -------------------------------------------------------------------------------
2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                (a)  /X/
                                                                      (b)  / /
- -------------------------------------------------------------------------------
3    SEC USE ONLY


- -------------------------------------------------------------------------------
4    SOURCE OF FUNDS*

     BK

- -------------------------------------------------------------------------------
5    CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED              / /
     PURSUANT TO ITEMS 2(d) or 2(e)

- -------------------------------------------------------------------------------
6    CITIZENSHIP OR PLACE OF ORGANIZATION

     Illinois

- -------------------------------------------------------------------------------
NUMBER OF                       7     SOLE VOTING POWER
SHARES
BENEFICIALLY                          2,252,400 (But see Items 2 and 5)
OWNED BY                        -----------------------------------------------
EACH                            8     SHARED VOTING POWER
REPORTING
PERSON                                -0-
                                -----------------------------------------------
                                9     SOLE DISPOSITIVE POWER

                                      2,252,400 (But see Items 2 and 5)
                                -----------------------------------------------
                                10   SHARED DISPOSITIVE POWER

                                     -0-

- -------------------------------------------------------------------------------
11   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     2,252,400 (But see Items 2 and 5)

- -------------------------------------------------------------------------------
12   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11)     
     EXCLUDES CERTAIN SHARES*


- -------------------------------------------------------------------------------
13   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

     12.77%

- -------------------------------------------------------------------------------
14   TYPE OF REPORTING PERSON

     00

- -------------------------------------------------------------------------------
                    *SEE INSTRUCTIONS BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.


<PAGE>   3

                                 SCHEDULE 13D

CUSIP NO.  009728 10 6                                    PAGE  3  OF 8  PAGES
          ------------------                                   ----  ----
===============================================================================
1    NAME OF REPORTING PERSON
     S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     John N. Kapoor
- -------------------------------------------------------------------------------
2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a)  /X/
                                                                       (b)  / /
- -------------------------------------------------------------------------------
3    SEC USE ONLY


- -------------------------------------------------------------------------------
4    SOURCE OF FUNDS*


- -------------------------------------------------------------------------------
5    CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED               / /
     PURSUANT TO ITEMS 2(d) or 2(e)

  
- -------------------------------------------------------------------------------
6    CITIZENSHIP OR PLACE OF ORGANIZATION

     U.S.

- -------------------------------------------------------------------------------
NUMBER OF                       7     SOLE VOTING POWER
SHARES
BENEFICIALLY                          4,300,369 (But see Items 2 and 5)
OWNED BY                        -----------------------------------------------
EACH                            8     SHARED VOTING POWER
REPORTING
PERSON                                -0- (But see Items 2 and 5)
                                -----------------------------------------------
                                9      SOLE DISPOSITIVE POWER

                                       4,300,369 (But see Items 2 and 5)
                                -----------------------------------------------
                                10     SHARED DISPOSITIVE POWER

                                       -0- (But see Items 2 and 5)

- -------------------------------------------------------------------------------
11   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     4,300,369 (But see Items 2 and 5)

- -------------------------------------------------------------------------------
12   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11)
     EXCLUDES CERTAIN SHARES*


- -------------------------------------------------------------------------------
13   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

     24.39%

- -------------------------------------------------------------------------------
14   TYPE OF REPORTING PERSON

     IN

- -------------------------------------------------------------------------------
                    *SEE INSTRUCTIONS BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.


<PAGE>   4

                                 SCHEDULE 13D

CUSIP NO.  009728 10 6                                      PAGE 4  OF 8  PAGES
          -----------------                                     ----  ----
===============================================================================
1    NAME OF REPORTING PERSON
     S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     EJ Financial Investments VIII, L.P. 

- -------------------------------------------------------------------------------
2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a)  /X/
                                                                       (b)  / /

- -------------------------------------------------------------------------------
3    SEC USE ONLY


- -------------------------------------------------------------------------------
4    SOURCE OF FUNDS*


- -------------------------------------------------------------------------------
5    CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED               / /
     PURSUANT TO ITEMS 2(d) or 2(e)

- -------------------------------------------------------------------------------
6    CITIZENSHIP OR PLACE OF ORGANIZATION

     Delaware

- -------------------------------------------------------------------------------
NUMBER OF                       7     SOLE VOTING POWER
SHARES
BENEFICIALLY                          2,000,000 (But see Items 2 and 5)
OWNED BY                        -----------------------------------------------
EACH                            8     SHARED VOTING POWER
REPORTING
PERSON                                -0- (But see Items 2 and 5)
                                -----------------------------------------------
                                9     SOLE DISPOSITIVE POWER

                                      2,000,000 (But see Items 2 and 5)
                                -----------------------------------------------
                                10    SHARED DISPOSITIVE POWER

                                       -0- (But see Items 2 and 5)

- -------------------------------------------------------------------------------
11   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     2,000,000 (But see Items 2 and 5)

- -------------------------------------------------------------------------------
12   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11)
     EXCLUDES CERTAIN SHARES*


- -------------------------------------------------------------------------------
13   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

     11.34%

- -------------------------------------------------------------------------------
14   TYPE OF REPORTING PERSON

     PN

- -------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!
          INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
      (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.



<PAGE>   5


                                 SCHEDULE 13D

CUSIP NO.  009728 10 6                                      PAGE 5  OF 8  PAGES
          ----------------
===============================================================================
1    NAME OF REPORTING PERSON
     S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

     Editha Kapoor

- -------------------------------------------------------------------------------
2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*                 (a)  /X/
                                                                       (b)  / /
- -------------------------------------------------------------------------------
3    SEC USE ONLY


- -------------------------------------------------------------------------------
4    SOURCE OF FUNDS*

- -------------------------------------------------------------------------------
5    CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED               / /
     PURSUANT TO ITEMS 2(d) or 2(e)

- -------------------------------------------------------------------------------
6    CITIZENSHIP OR PLACE OF ORGANIZATION

     USA

- -------------------------------------------------------------------------------
NUMBER OF                       7     SOLE VOTING POWER
SHARES
BENEFICIALLY                          63,600 (But see Items 2 and 5)
OWNED BY                        -----------------------------------------------
EACH                            8     SHARED VOTING POWER
REPORTING
PERSON                                -0- (But see Items 2 and 5)
                                -----------------------------------------------
                                9     SOLE DISPOSITIVE POWER

                                      63,600 (But see Items 2 and 5)
                                -----------------------------------------------
                                10    SHARED DISPOSITIVE POWER

                                      -0- (But see Items 2 and 5)

- -------------------------------------------------------------------------------
11   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     63,600 (But see Items 2 and 5)

- -------------------------------------------------------------------------------
12   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11)
     EXCLUDES CERTAIN SHARES*



- -------------------------------------------------------------------------------
13   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

     .36% (But see Items 2 and 5)

- -------------------------------------------------------------------------------
14   TYPE OF REPORTING PERSON

     IN

- -------------------------------------------------------------------------------
                    *SEE INSTRUCTIONS BEFORE FILLING OUT!
         INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
     (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.



<PAGE>   6


This Amendment No. 6 (the "Amendment") to Schedule 13D is filed jointly by the
John N. Kapoor Trust, dated September 20, 1989 (the "Trust"), of which John N.
Kapoor is Trustee and sole beneficiary, John N. Kapoor, Editha Kapoor, wife of
John N. Kapoor, and EJ Financial Investments VIII, L.P., a Delaware limited
partnership ("EJ VIII"), of which John N. Kapoor is managing general partner
and Editha Kapoor is the other general partner.  This Amendment relates to the
common stock, no par value ("Akorn Common Stock") of Akorn, Inc., a Louisiana
corporation ("Akorn"), and is being filed pursuant to Rule 13d-2 of the General
Rules and Regulations under the Securities Exchange Act of 1934, as amended.

Item 2  IDENTITY AND BACKGROUND.  The Trust is an Illinois trust, dated  
        September 20, 1989, of which John N. Kapoor is the Trustee and
        sole beneficiary.  EJ VIII is a Delaware limited partnership which was
        formed to hold the investment in the Issuer.  The address of EJ VIII's
        principal business and principal office is 225 East Deerpath, Suite 250,
        Lake Forest, Illinois 60045.  John N. Kapoor and Editha Kapoor are each
        residents of the United States.  At the present time, John N. Kapoor is
        President and Chairman of the Board of Directors of EJ Financial        
        Enterprises Inc., a Delaware corporation ("EJ"), 225 East Deerpath,
        Suite 250, Lake Forest, Illinois 60045.  At the present time, Editha
        Kapoor is a consultant for EJ.  During the last five years, neither the
        Trust, John N. Kapoor, Editha Kapoor nor EJ VIII (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 and, as a result of
        such proceeding, was or is subject to a judgment, decree or final order
        in joining future violations of or prohibiting or mandating activity
        subject to, federal or state securities laws or finding any violations
        with respect to such laws.

Item 3  SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION. On December 30, 1997
        in consideration of a payment of $2,000,000 by the Trust to Akorn, the
        Trust exercised the Warrant held by the Trust and received 1,000,000
        shares of Akorn's Common Stock.  The funds for this purchase came from
        a loan by The Northern Trust Bank to the Trust pursuant to an existing
        line of credit.  In addition, on December 23, 1997, the Trust made
        gifts of 44,600 shares of Akorn's Common Stock to various entities and
        persons, including gifts of 33,600 shares of Akorn Common Stock to
        Editha Kapoor in her capacity as trustee of four trusts established for
        the benefit of the children of John Kapoor and Editha Kapoor (the
        "Childrens' Trusts").  Finally, in consideration of Kapoor's
        service on Akorn's board of directors, on February 28, 1997, Kapoor
        received vested options to purchase 5,000 shares of Akorn Common
        Stock at an exercise price of $2.28 per share.


                             Page  6  of  8  Pages
                                 ----   ----

<PAGE>   7



Item 4  PURPOSE OF TRANSACTION. On December 30, 1997, the Trust exercised its
        Warrant to acquire 1,000,000 shares of Akorn common stock at an
        aggregate purchase price of $2,000,000.  The Warrant was scheduled to
        expire on December 31, 1997.


Item 5  INTEREST IN SECURITIES OF THE ISSUER.
        ------------------------------------

            (a)  As of the date hereof, (i) the Trust owns (A)  2,232,400 
                 shares of Akorn Common Stock representing 12.77% of the
                 issued and outstanding shares of Akorn Common Stock, and
                 (B) options to purchase 20,000 shares of Akorn Common Stock
                 representing .1% of the issued and outstanding shares of Akorn
                 Common Stock; (ii) John N. Kapoor owns (A) presently
                 exercisable options to purchase 47,969 shares of Akorn Common
                 Stock representing .27% of the issued and outstanding shares of
                 Akorn Common Stock, (B) an indirect interest in 20,000
                 presently exercisable options held by the Trust representing
                 .1% of the issued and outstanding shares of Akorn Common Stock,
                 (C) 2,232,400 shares of Akorn Common Stock representing 12.77%
                 of the issued and outstanding shares of Akorn Common Stock
                 through the Trust, and (D) 2,000,000 shares of Akorn Common
                 Stock, representing 11.3% of the issued and outstanding shares
                 of Akorn Common Stock in his capacity as General Partner of EJ
                 VIII; (iii) Editha Kapoor owns 63,600 shares of Akorn Common
                 Stock representing .2% of the issued and outstanding shares of
                 Akorn Common Stock in her capacity as Trustee of four trusts
                 established for the benefit of the children of John Kapoor and
                 Editha Kapoor (the "Childrens' Trusts"); and (iv) EJ VIII owns
                 2,000,000 shares of Akorn Common Stock representing 11.3% of
                 the issued and outstanding shares of Akorn Common Stock.
 
            (b)  The Trust has sole voting and dispositive power over 
                 2,252,000 shares of Akorn Common Stock and does not share
                 voting power or dispositive power over any other shares of
                 Akorn Common Stock.  John N. Kapoor has sole voting and
                 dispositive power over 4,300,369 shares of Akorn Common Stock
                 (comprised of the shares of Akorn Common Stock held by the
                 Trust and EJ VIII and the Option Shares).  Editha Kapoor has
                 sole voting and dispositive power over 63,600 shares of Akorn
                 Common Stock representing the shares held in the Childrens'
                 Trusts.  EJ VIII has sole voting and dispositive power over
                 2,000,000 shares of Akorn Common Stock and does not share
                 voting or  dispositive power over any other shares of Akorn
                 Common Stock.

            (c)  Except as set forth above, the Reporting Persons
                 do not beneficially own any shares of Akorn Common Stock and
                 have effected no transactions in shares of Akorn Common Stock
                 during the preceding 60 days.

            (d)  Inapplicable.

            (e)  Inapplicable.

                             Page  7  of  8  Pages
                                 ----   ----


<PAGE>   8

                                  SIGNATURE


     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.


                                        John N. Kapoor Trust
                                        dated September 20, 1989


January 8, 1998                         By: /s/ John N. Kapoor, Trustee
                                           ----------------------------
                                           John N. Kapoor as Trustee

                                            /s/ John N. Kapoor
January 8, 1998                            -----------------------------
                                           John N. Kapoor

                                            /s/ Editha Kapoor
January 8, 1998                            -----------------------------
                                           Editha Kapoor



                                           EJ FINANCIAL INVESTMENTS VIII, L.P.



January 8, 1998                            By: /s/ John N. Kapoor
                                              --------------------------        
                                              John N. Kapoor, Managing
                                              General Partner




                             Page  8  of  8  Pages
                                 ----   ----