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                                SECOND AMENDMENT

           SECOND AMENDMENT dated as of August 13, 1998, (the "Amendment"), with
respect to the Credit Agreement dated as of August 20, 1997 (such agreement as
it has been amended prior to the date hereof, the "Credit Agreement"), by and
among PDK LABS INC. and FUTUREBIOTICS, INC., as Co-Borrowers (the
"Co-Borrowers"), and EUROPEAN AMERICAN BANK, a New York banking corporation
("EAB"), as Agent and as a Bank and the Banks party hereto.

                                    RECITALS

           The Co-Borrowers have requested and the Banks have agreed, subject to
the terms and conditions of this Amendment, to waive and amend certain
provisions of the Credit Agreement as herein set forth. Capitalized terms used
herein and not defined herein shall have the meanings given to them in the
Credit Agreement.

           Accordingly, in consideration of the premises and of the mutual
covenants and agreements hereinafter set forth, the parties hereto agree as
follows:

           I.        Amendments.

           Section 1.1. Section 1.1 of the Credit Agreement is hereby amended by
inserting the following definitions therein immediately prior to the definition
of "Debt":

                     "Consulting Agreement" means a consulting agreement to be 
executed by and between PDK and Michael Krasnoff having a term of not less than
three (3) years pursuant to which Mr. Krasnoff shall provide consulting
services to PDK in the areas of marketing, finance, administration and mergers
and acquisitions at least sixteen (16) Business Days per month and which shall
include a non-compete agreement which will prohibit Mr. Krasnoff from being
employed by or from providing consulting services to any competitor of PDK,
which agreement shall be reasonably satisfactory to the Banks.

           Section 1.2. The definition of the term "Revolving Credit Commitment"
contained in Section 1.1 of the Credit Agreement is hereby amended by deleting
the chart therefrom and by substituting the following in its place:

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           Bank                              Commitment
           ----                              ----------

           EAB                               $5,300,000

           National Bank of Canada           $2,350,000

           Bank Leumi USA                    $2,350,000

           Section 1.3. The definition of the term "Revolving Credit Note"
contained in Section 1.1 of the Credit Agreement is hereby amended by inserting
the following phrase at the end thereof: ", or any note issued in substitution
or replacement thereof."

           Section 1.4. The  definition  of the term "Term Note" contained in 
Section 1.1 of the Credit Agreement is hereby amended by inserting the
following phrase at the end thereof: ", or any note issued in substitution or
replacement thereof."

           Section 1.5. Article 6 of the Credit Agreement is hereby amended by 
inserting the following in a new Section 6.20 at the end thereof:

                     Section 6.20. Year 2000. Any reprogramming or other
                     corrective modifications required to permit the proper
                     functioning, in and following the year 2000, of (i)
                     Co-Borrower's and their Subsidiaries' computer systems and
                     (ii) equipment containing embedded microchips (including
                     systems and equipment supplied by others or with which the
                     Co-Borrowers' or their Subsidiaries' systems interface) and
                     the testing of all such systems and equipment, as so
                     reprogrammed, will be completed by January 1, 1999. The
                     cost to the Co-Borrowers and their Subsidiaries of such
                     reprogramming, modifications and testing and of the
                     reasonably foreseeable consequences of year 2000 to the
                     undersigned and its subsidiaries (including, without
                     limitation, reprogramming errors and the failure of others'
                     systems or equipment) will not result in the occurrence of
                     an Event of Default or result in a Material Adverse Change.
                     Except for such of the reprogramming and modifications
                     referred to in the preceding sentence as may be necessary,
                     the computer and management information systems of the
                     Co-Borrowers and their Subsidiaries are, and with ordinary
                     course upgrading and maintenance, will continue for the
                     term of this Agreement to be, sufficient to permit the
                     Co-Borrowers to conduct their business.

           Section 1.6. Section  8.11 of the Credit  Agreement  is hereby
amended and restated to provide in its entirety as follows:

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                     "Fail to maintain Michael B. Krasnoff (i) in a reasonably
                     active full time capacity as the President of PDK and as an
                     officer to Futurebiotics, responsible for the day to day
                     operations of each of the Co-Borrowers or (ii) as a
                     consultant to PDK and Futurebiotics pursuant to the terms
                     of the Consulting Agreement."

           II.       Conditions. The amendments provided for pursuant to Section
I hereof shall become effective only upon satisfaction of the following
conditions precedent:

                     (a)       The Agent shall have received each of the 
                               following, in form and substance satisfactory to 
                               the Agent and its counsel.

                               (i)        This Amendment and amended and 
                                          restated Revolving Credit Notes 
                                          executed by the Co-Borrowers in favor 
                                          of each Bank;

                               (ii)       a certificate of the Secretary of 
                                          Compare Generiks, Inc. (the
                                          "New Guarantor") dated the date of
                                          this Amendment, attesting to all 
                                          corporate action taken by such entity,
                                          including resolutions of its Board of 
                                          Directors authorizing the execution, 
                                          delivery and performance of its 
                                          Guarantee and each other document to 
                                          be delivered pursuant to this 
                                          Agreement, together with certified 
                                          copies of the certificate or articles 
                                          of incorporation and the by-laws of 
                                          the New Guarantor; and, such 
                                          certificate shall state that the
                                          resolutions and corporate documents
                                          thereby certified have not been 
                                          amended, modified, revoked or 
                                          rescinded as of the date of such 
                                          certificate;

                               (iii)      a certificate of the Secretary of the
                                          New Guarantor, dated the Closing Date,
                                          certifying the names and true
                                          signatures of the officers of such
                                          entity authorized to sign the Facility
                                          Documents and the other documents to
                                          be delivered by such entity under this
                                          Agreement;

                               (iv)       a certificate of a duly authorized
                                          officer of each of the Co-Borrowers,
                                          dated the date of this Agreement,
                                          stating that the representations and
                                          warranties in Article 6 are true and
                                          correct on such date as though made on
                                          and as of such date and that no event
                                          has occurred and is continuing which
                                          constitutes a Default or Event of
                                          Default;

                               (v)        a Guarantor Security  Agreement duly 
                                          executed by the New Guarantor, 
                                          together with (A) fully completed and 
                                          executed  financing  statements on 
                                          Form UCC-1, in proper form for filing
                                          duly filed  under the Uniform 
                                          Commercial Code  in all jurisdictions
                                          necessary  or, in the reasonable  
                                          discretion of the Agent, desirable to 

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                                          perfect the security  interests  to be
                                          granted  hereunder and under the 
                                          Guarantor  Security  Agreement and (B)
                                          UCC search  results identifying  all
                                          of the financing statements on file 
                                          with respect to the New Guarantor in
                                          all  jurisdictions  referred to under 
                                          clause (A) hereof,  indicating that no
                                          party claims an interest in any of the
                                          Collateral;

                               (vi)       a favorable opinion of counsel for the
                                          New Guarantor dated the Closing Date,
                                          in form and substance satisfactory to
                                          the Agent and its counsel;

                               (vii)      satisfactory evidence that the New
                                          Guarantor is duly organized, validly
                                          existing and in good standing under
                                          the laws of their respective
                                          jurisdictions of incorporation and
                                          each other jurisdiction where
                                          qualification is necessary; and

                               (viii)     such other documents, instruments,
                                          agreements, approvals, opinions and
                                          evidence as the Agent may reasonably
                                          require.

           III.      Miscellaneous.

                     (a) This Amendment shall be governed by and construed in
accordance with the laws of the State of New York.

                     (b) All terms used herein shall have the same meaning as in
the Credit Agreement, as amended hereby, unless specifically defined herein.

                     (c) This Amendment shall constitute a Facility Document.

                     (d) As expressly amended hereby, the Credit Agreement
remains in full force and effect in accordance with the terms thereof. The
Credit Agreement is ratified and confirmed in all respects by the Co-Borrowers.
The amendments herein are limited specifically to the matters set forth above
and for the specific instance and purposes for which given and do not
constitute directly or by implication an amendment or waiver of any other
provisions of the Credit Agreement or a waiver of any Event of Default or event
which upon notice, lapse of time or both would constitute an Event of Default
which may occur or may have occurred under the Credit Agreement or any other
Facility Document.

                     (e) The Co-Borrowers hereby represent and warrant that (i)
the representations and warranties by the Co-Borrowers and each Guarantor
pursuant to the Credit Agreement and each other Facility Document are true and
correct on the date hereof, and (ii) after giving effect to this Amendment, no
Event of Default or event which upon notice, lapse of 

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time or both would constitute an Event of Default exists under the Credit
Agreement or any other Facility Document.

                     (f) This Amendment may be executed in one or more
counterparts, each of which shall constitute an original, but all of which,
when taken together, shall constitute but one Amendment.

           IN WITNESS WHEREOF, the Co-Borrowers, the Agent and the Banks have
caused this Amendment and Waiver to be duly executed by their duly authorized
officers as of the day and year first above written.

                                              PDK LABS INC.

                                              By:
                                                 -------------------------------
                                              Title:

                                              FUTUREBIOTICS, INC.

                                              By:
                                                 -------------------------------
                                              Title:

                                              EUROPEAN AMERICAN BANK,
                                              as Agent and as a Bank

                                              By:
                                                 -------------------------------
                                              Title:

                                              BANK LEUMI USA, as a Bank

                                              By:
                                                 -------------------------------
                                              Title:

                                              NATIONAL BANK OF CANADA, as a Bank

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                                              By:
                                                 -------------------------------
                                              Title: