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                                                                   Exhibit 10.83

                               AMENDMENT AGREEMENT

         AMENDMENT AGREEMENT, dated as of November 1, 1998 by and between PDK
Labs Inc., a New York corporation, with offices at 145 Ricefield Lane,
Hauppauge, New York 11788 ("PDK") and Compare Generiks, Inc., a Delaware
corporation, with offices at 300 Oser Avenue, Hauppauge, New York 11788 ("CGI").

         WHEREAS, PDK and CGI have heretofore entered into an Exclusive Supply
and Licensing Agreement, dated as of March 24, 1997 (the "Agreement"); as
amended April 1, 1998;

         WHEREAS, Section 2(d) of the Agreement requires CGI to pay invoices
within sixty (60) days of the date of shipment of the related Products (as
defined in the Agreement);

         WHEREAS, the Agreement contains a provision permitting PDK to suspend
its obligations to perform under the Agreement in the event of an Event of Force
Majeure (as defined in the Agreement);

         WHEREAS, CGI is in default of the provisions of Section 2(d) of the
Agreement requiring CGI to pay invoices within sixty (60) days from the date of
shipment of the related Products and, in addition, an Event of Force Majeure (as
defined in the Agreement) has occurred and, in consideration for PDK agreeing to
waive (a) the breach by CGI of provisions contained in Section 2(d) of the
Agreement, and (b) its right to suspend performance of its obligations under the
Agreement, the parties hereto desire to (i) amend the Payment Provision to
provide for the payment by CGI to PDK of a higher amount, and (ii) amend the
Agreement to reflect PDK's agreement not to sell any products containing either
ephedrine or pseudoephedrine to convenience stores or to any suppliers of
convenience stores during the Term (as defined in the Agreement).

         The terms which are not defined herein shall have the respective
meanings ascribed to them in the Agreement.


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         NOW, THEREFORE, for valid and good consideration, the parties hereto
agree as follows:

         1)       The sentence of Section 2(a) of the Agreement shall be deleted
                  in its entirety and shall be replaced with the following four
                  sentences:

                  "(a) In consideration for the waiver by PDK of (i) its rights
                  with respect to the continuing breach by CGI of the payment
                  provisions of Section 2(d) of this Agreement, and (ii) the
                  right to suspend performance of its obligations under this
                  Agreement as a result of the occurrence of an Event of Force
                  Majeure (as defined in Section 5 below), CGI agrees to pay PDK
                  $1.50 per bottle of Products shipped to CGI (the "Basic
                  Payment"), except as otherwise provided herein a paragraphs 2
                  and 6; provided that said waiver shall not constitute a waiver
                  of PDK's right to terminate this Agreement and the License
                  hereunder or to exercise any rights available to PDK upon
                  reoccurrence or continuance of such acts or events. In
                  addition to the Basic Payment, CGI shall also pay PDK the
                  difference between 93% of the sales price as invoiced to the
                  customer of each bottle and $1.50 per bottle (the AExcess
                  Payment@). The Excess Payment is payable monthly, in arrears,
                  within 15 days of the end of the month in which CGI received
                  payment for the related Products."

         2)       The following paragraph shall be added to Section 6 of the
                  Agreement as paragraph (b) thereof:

                  "(b) In consideration for the amendment by the parties hereto
                  the provisions of Section 2(a) above, PDK hereby agrees and
                  acknowledges that from and after the date of this Amendment
                  Agreement PDK shall not sell, manufacture, market or
                  distribute any products containing ephedrine or
                  pseudoephedrine to convenience stores or to any suppliers of
                  convenience stores during the Term."


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         3)       Except as herein above amended, all of the terms and
                  provisions of the Agreement shall remain in full force and
                  effect.

         4)       This Amendment shall be governed by and construed in
                  accordance with the laws of the State of New York, without
                  regard to principles of conflicts of law.


         IN WITNESS WHEREOF, the parties have executed this Amendment Agreement
as of the day and year first above written.


                                           PDK LABS INC.


                                           By: ______________________________
                                                 Reginald Spinello, President




                                           COMPARE GENERIKS, INC.


                                           By: ______________________________
                                                 Thomas A. Keith, President