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                                    GUARANTY

         WHEREAS, European American Bank and the parties identified. as "Banks"
therein  (the  "Banks")  have  entered  into a  Credit  Agreement  (the  "Credit
Agreement",  dated August 20, 1997, with PDK Labs Inc. and  Futurebiotics,  Inc.
(the "Debtor); and

         WHEREAS, under the terms of the Credit Agreement, the Banks have agreed
to extend credit to the Debtors, which indebtedness is evidenced by certain
promissory notes of the Debtors (the "Notes"), to be dated on and after August
13, 1998, in the aggregate principal amount of $18,500,000;

         WHEREAS, the undersigned (the "Guarantor") has derived or will derive
direct benefit from the extension of credit to the Debtors; and

         WHEREAS, the Banks will not extend such credit unless, among other
conditions, the undersigned Guarantor shall have executed and delivered this
Guaranty,

         NOW, THEREFORE, in consideration of the Banks extending such credit to
the Debtors and other benefits accruing to the Guarantor, the receipt and
sufficiency of which are hereby acknowledged, the Guarantor hereby makes the
following representations and warranties to the Banks and hereby covenants and
agrees with the Banks as follows:

         1. Subject to the provisions of Section 13 hereof, the Guarantor
irrevocably and unconditionally, guarantees to the Banks (i) timely payment in
full by Debtors to the Banks of all payments due pursuant to the Notes (it being
understood that this is a guarantee of payment and not of collection), and (ii)
timely payment and/or performance, as applicable, of all other

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payment and performance obligations of Debtors pursuant to the Notes, the Credit
Agreement and all other documents and instruments executed in connection
therewith, or pursuant to any amendment, modification or supplement to any of
the foregoing (all of the foregoing under clauses (i) and (ii) being
collectively referred to as the "Guaranteed Obligations"). If Debtors shall
default in payment of any amount due pursuant to the Notes beyond any applicable
grace period or otherwise default beyond any applicable grace period in the
performance of the Guaranteed Obligations, the Guarantor irrevocably and
unconditionally agrees to pay to the Banks upon demand the amount in default or
to cure the default if it is a non-payment default (it being understood,
however, that a non-payment may result in the acceleration of all indebtedness
and a demand for payment in full by the Guarantor under the Guaranty). The
Guarantor understands, agrees and confirms that the Banks may enforce this
Guaranty up to the full amount of the Guaranteed Obligations owing against the
Guarantor without proceeding against the Debtors, or any of them, against any
security for the Guaranteed Obligations or against any other guarantor under any
other guarantee covering the Guaranteed Obligations.

         2. The Guarantor hereby acknowledges the Guaranteed Obligations and
hereby expressly waives: (i) presentment and demand for payment of the principal
of or interest thereon or any other sums of any nature whatsoever with respect
thereto, (ii) notice of acceptance of this Guaranty, or of the extension of
credit to the Debtors, (iii) notice of any default hereunder or under any
agreements between the Banks and the Debtors with respect to the Guaranteed
Obligations, and of all indulgences with respect thereto, (iv) demand on the
Debtors for observance or performance of, or enforcement of any terms or
provisions of any agreements between the Banks and the Debtors with respect to
the Guaranteed Obligations, (v) to the

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maximum extent permitted by applicable law and except as otherwise provided
herein, the benefit of all laws now or hereafter in effect in any way limiting
or restricting the liability of the Guarantor under this Guaranty, including any
and all right to stay of execution and exemption of property in any action to
enforce the liability of the Guarantor hereunder and (vi) any other event or
circumstance which may constitute a release of or defense to the obligors under
any of the Guaranteed Obligations or the Guarantor under this Guaranty. In the
event this Guaranty shall be enforced by suit or otherwise, the Guarantor shall
pay the Banks, on demand, for all reasonable fees and expenses incurred by the
Banks in connection therewith, including, without limitation, the reasonable
fees and expenses of the Banks' counsel.

         3. The Banks, in their sole and absolute discretion, may at any time
and from time to time without the consent of, or notice to, the Guarantor
without incurring responsibility to the Guarantor, without impairing or
releasing the obligations of Guarantor hereunder, upon or without any terms or
conditions. and in whole or in part (but in all events subject to the applicable
provisions of the Credit Agreement);

              (a) by agreement with the Debtors, change the manner, place or
terms of payment of, and/or change or extend the time of payment of, increase
the amount of, or renew or alter any of the Guaranteed Obligations, any security
therefor, or any liability incurred directly or indirectly in respect thereof,
and the Guaranty herein made shall apply to the Guaranteed Obligations as so
changed, extended, increased, renewed or altered;

              (b) exercise or refrain from exercising any rights against the
Debtors, or any of them or others or otherwise act or refrain from acting;

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              (c) release, settle or compromise any of the Guaranteed
Obligations, any security therefor or any liability (including any of those
hereunder) incurred directly or indirectly in respect thereof or hereof, and may
subordinate the payment of all or any part thereof to the payment of any
liability (whether due or not) of Debtors, or any of them, to creditors of
Debtors, or any of them, other than Guarantor;

              (d) consent to or waive any breach of, or any act, omission or
default under, the Credit Agreement or the Notes, or any of the instruments or
agreements referred to therein, or otherwise amend, modify or supplement any of
the foregoing;

              (e) agree to the substitution, exchange, release or other
disposition of all or any part of any property securing the Guaranteed
Obligations;

              (f) make advances for the purposes of performing any term or
covenant contained in any agreement between the Banks and the Debtors with
respect to which the Debtors may be in default;

              (g) assign or otherwise transfer all or any part of the Guaranteed
Obligations; and

              (h) deal in all respects with the Debtors as if this Guaranty were
not in affect.

         4. No invalidity, irregularity or unenforceability of all or any part
of the Guaranteed Obligations or of any security therefor shall affect, impair
or be a defense to this Guaranty, and this Guaranty is a primary obligation of
the Guarantor.

         5. This Guaranty is a continuing one and all liabilities to which it
applies or may apply under the terms hereof shall be conclusively presumed to
have been created in reliance hereon. No failure or delay on the part of the
Banks (whether acting individually or through an agent), or

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any of them, in exercising any right, power or privilege hereunder shall operate
as a waiver thereof, nor shall any single or partial exercise of any right,
power or privilege hereunder preclude any other or further exercise thereof or
the exercise of any other right, power or privilege. The rights and remedies
herein expressly specified are cumulative and not exclusive of any rights or
remedies which the Banks (whether acting individually or through an agent), or
any of them, or any subsequent holder of any Guaranteed Obligations would
otherwise have. No notice to or demand on the Guarantor in any case shall
entitle the Guarantor to any other or further notice or demand in similar or
other circumstances or constitute a waiver of the rights of the Banks (whether
acting individually or through an agent), or any of them, or any holder of any
Guaranteed Obligations to any other or further action in any circumstances
without notice or demand.

         6. This is a guarantee of payment and not of collection, and the
liability of the Guarantor under this Guaranty shall be primary, direct and
immediate, and not conditional or contingent upon pursuit by the Banks of any
remedies they may have against the Debtors, or any of them, with respect to the
Guaranteed Obligations, whether pursuant to the terms thereof or by law, or
against any other person or entity or against any other collateral. Without
limiting the generality of the foregoing, the Banks shall not be required to
make any demand on the Debtors, or any of them, or to sell at foreclosure or
otherwise pursue or exhaust their remedies against the property securing the
Debtor's obligations for the Guaranteed Obligations or against the Debtors, or
any of diem, or against any other person or entity or against any other
collateral whatsoever, before, simultaneously with or after enforcing their
rights and remedies hereunder against the Guarantor, Any one or more successive
or concurrent actions may be brought hereon against the Guarantor

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either in the same action, if any, brought against the Debtors, or any of them,
or in separate actions, as often as the Banks may deem advisable.

         7. The Guarantor represents and warrants to the Banks that:

              (a) It is a corporation duly organized, validly existing and in
good standing under the laws of the jurisdiction of its incorporation and has
all corporate power and authority to own all of its properties and to carry on
its business as presently conducted and as contemplated by this Guaranty and has
corporate power and authority to execute and deliver this Guaranty and to
perform its obligations hereunder.

              (b) This Guaranty is and will be the legal, valid and binding
obligation of the Guarantor, enforceable in accordance with its terms, and the
execution, delivery and performance of this Guaranty and such other agreements,
documents and instruments and the performance of the transactions contemplated
hereunder have been and will be duly and validly authorized and approved by the
Board of Directors, and do not and will not require any consent or approval of
any third party or of the stockholders of the Guarantor other than consents
which have previously been obtained.

              (c) The execution and delivery of this Guaranty do not, and the
consummation of the transactions contemplated hereby will not, constitute a
violation of, and are not, and will not, be a default under or conflict with the
terms of the Certificate of Incorporation or By-laws of the Guarantor, or any
contract, lease, indenture, agreement, order, judgment, or decree to which it is
a party or by which it is bound or to which any of its assets are subject, which
in any case, or in the aggregate, could have a material adverse effect on its
ability to carry out its obligations under this Guaranty, and do not, and will
not, violate or constitute a default under any statute,

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rule, regulation, order or ordinance of any governmental, judicial or arbitral
body, which in any case, or in the aggregate, could have a material adverse
effect on its ability to carry out its obligations under this Guaranty.

              (d) Neither the execution, delivery or performance of this
Guarantee, nor the consummation of the transactions contemplated hereby,
requires the Guarantor to obtain any consent, authorization, approval or
registration under any law, rule or regulation, other than as contemplated
hereby or as previously obtained.

              (e) There is no suit, action or legal, administrative. arbitration
or other proceeding of any nature pending, or, to the knowledge of the
Guarantor, threatened, against it which might affect the legality or validity of
this Guaranty, or the transactions contemplated hereby, and there is not any
factual basis known to it for any such suit, action or proceeding.

         8. This Guaranty shall be binding upon the Guarantor and its successors
and assigns and shall inure to the benefit of the Banks and their respective
successors and permitted assigns. This Guaranty may not under any circumstances
be assigned by the Guarantor to any other person or entity without the express
prior written consent of each of the Banks.

         9. Neither this Guaranty nor any provision hereof may be changed,
waived, discharged or terminated except with the written consent of each of the
Banks.

         10. In the event that either Bank shall receive any payments on account
of any of the Guaranteed Obligations, whether directly or indirectly, and it
shall subsequently be determined that such payments were for any reason
improper, or a claim shall be made against such Bank that the same were
improper, and such Bank pursuant to court order shall return the same, the
Guarantor shall be liable, with the same effect as if the said payment had never
been paid to, or

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received by such Bank, for the amount of such repaid or returned payments,
notwithstanding the fact that they may theretofore have been credited on account
of the Guaranteed Obligations or any of them. Moreover, this Guaranty shall
remain effective or be reinstated, as the case may be, if at any time payment or
performance, or any part thereof, or any or all of the Guarantor's obligations
under this Guaranty is rescinded or must otherwise be restored or returned by
the Banks, or any of them, in connection with the insolvency, bankruptcy or
reorganization of the Guarantor or otherwise, all as though such payment or
performance had not been rendered. Notwithstanding any compromise, release,
discharge, settlement, extension, or adjustment of the Debtor's obligations or
any amendment, modification or stay of the Banks' rights against the Debtor that
may occur in any bankruptcy or reorganization case or proceeding concerning the
Debtor, whether or not assented to by the Banks, the Guarantor shall remain
fully obligated to discharge the Guarantor's obligations hereunder in accordance
with the terms of this Guaranty in effect on the date hereof. The Guarantor
assumes all risks of a bankruptcy or reorganization with respect to the Debtor.
In furtherance of this Section, the Banks shall not otherwise indicate the
satisfaction of the obligations of the parties represented herein until the
expiration of all applicable bankruptcy-related periods of time during which the
Debtor, the Guarantor or any third party would have the right to commence a
bankruptcy or reorganization proceeding with regard to the Debtor or the
Guarantor.

         11. All notices and other communications provided for under this
Guaranty and under any other document executed in connection herewith shall be
in writing (including telegraphic or telefax communication) and, unless the
party to be notified otherwise notifies the other party in writing as provided
herein, notices shall be given by telecopier, by certified or registered mail or

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by recognized overnight delivery service. If such notice is delivered to the
Guarantor such notice shall be addressed to the Guarantor at 60 Davids Drive,
Hauppauge, New York 11788, telecopier (516) 273-0021, Attn: Thomas A. Keith,
President and, if to the Banks, at the Agent's address listed on the signature
pages of the Credit Agreement; or as to each party, at such other address as
shall be designated by such party in a written notice to the other parties
complying as to delivery with the terms of this Section 11. Notices shall be
effective (a) if given by registered or certified mail, on the third day after
deposit in the mails with postage prepaid, addressed as aforesaid; (b) if given
by recognized overnight delivery service, on the business day following deposit
with such service, addressed as aforesaid; and (c) if given by telecopy, when
the telecopy is transmitted to the telecopy number, as aforesaid; provided that
all notices to the Banks shall be effective on receipt.

         12. This Guaranty and the rights and obligations of the Banks and of
the undersigned hereunder shall be governed and be construed in accordance with
the laws of the State of New York applicable to agreements made and to be wholly
performed in the State of New York. The Guarantor hereby irrevocably submits to
the jurisdiction of any New York State or United States Federal Court sitting in
New York County, Nassau County or Suffolk County over any action or proceeding
arising out of or relating to the Guaranty, and the Guarantor hereby irrevocably
agrees that all claims in respect of such action or proceeding may be heard and
determined in such New York State or Federal court. The Guarantor irrevocably
consents to service of any and all process in any such action or proceeding by
the mailing (by registered or certified mail) of copies of such process to it as
its address specified in Section 11. The Guarantor agrees that a final judgment
in any such action or proceeding shall be conclusive and may be enforced in
other

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jurisdictions by suit on the judgment or in any other manner provided by law.
The Guarantor further waives any objection to venue in such State or Federal
court and any objection to an action or proceeding in such State or Federal
Court on the basis of forum non conveniens. Nothing in this Section shall limit
the rights of any Bank to serve legal process in any other manner permitted by
law or affect the right of the Banks to bring any action or proceeding against
the Guarantor in the courts of any other jurisdiction. To the extent that the
Guarantor has or hereafter may acquire immunity from jurisdiction of any court
or from any legal process with respect to themselves or their property, the
Guarantor hereby waives, to the extent permitted by applicable law, such
immunity respect of its obligations hereunder.

         13. Notwithstanding any other provision of this Guaranty, in no event
that the Guarantor's obligations hereunder exceed the sum of (i) the Debtor's
investment in the Guarantor as reflected on the Debtor's financial statements at
such time plus (ii) the aggregate amount of accounts payable by the Guarantor to
the Debtor at such time.

         14. THE PARTIES HERETO WAIVE ANY RIGHT TO A TRIAL BY JURY IN CONNECTION
HEREWITH TO THE EXTENT PERMITTED BY APPLICABLE LAW.

         IN WITNESS WHEREOF, the Guarantor have caused this Guaranty to be
executed and delivered as of August 13, 1998.

                                        THE GUARANTOR:

                                        COMPARE GENERIKS, INC.

                                        By:
                                            ------------------------------------
                                                            , President

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