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                               AMENDMENT AGREEMENT


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

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

         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, the Agreement contains a provision (the "Payment Provision")
providing for the payment by CGI to PDK of an amount equal to PDK's Material
Cost (as defined in the Agreement) plus fifty percent (50%) for the Products (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 the 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


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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.

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

         1. The first 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 $1.20 per bottle and $.12 per packet of
         Products shipped to CGI (the "Basic Payment"), except as otherwise
         provided herein at 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 or packet and
         the related payment per bottle or packet as set forth above in this
         Section 2(a) (the "Excess Payment"). The Excess Payment is payable
         monthly, in arrears, within fifteen (15) days of the end of the month
         in which CGI received payment for the related Products.



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         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 to 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."

         3. Except as hereinabove 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:   /s/ Michael Krasnoff
                                               --------------------------------
                                                 Michael Krasnoff, President

                                                 COMPARE GENERIKS, INC.


                                            By:   /s/ Thomas A. Keith
                                               --------------------------------
                                                  Thomas A. Keith, President

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