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                                                                    Exhibit 10.1

                                 AMENDMENT NO. 1
                                 ---------------



         AMENDMENT NO. 1 (this "AMENDMENT"), dated as of April 3, 2000, to the
Credit Agreement (as the same may be amended, supplemented or otherwise modified
from time to time, the "CREDIT AGREEMENT"), dated as of September 1, 1999, among
PENTON MEDIA, INC. (the "BORROWER"), the LENDERS party thereto, BANC OF AMERICA
SECURITIES, LLC, as Syndication Agent, THE FIRST NATIONAL BANK OF CHICAGO, as
Documentation Agent and THE BANK OF NEW YORK, as Administrative Agent.

                                    RECITALS
                                    --------

         I. Capitalized terms used herein and not defined herein shall have the
meanings assigned to such terms in the Credit Agreement.


         II. The Borrower has requested that the Administrative Agent agree to
amend the Credit Agreement upon the terms and conditions contained in this
Amendment, and the Administrative Agent is willing so to agree.


         Accordingly, in consideration of the Recitals and the terms and
conditions hereinafter set forth, and for other good and valuable consideration,
the receipt and adequacy of which are hereby acknowledged, the Borrower and the
Administrative Agent hereby agree as follows:

         1. Section 1.1 of the Credit Agreement is hereby amended by adding the
following defined terms thereto in alphabetical order:

                  "HEALTHWELL" means Healthwell.com, Inc., a Delaware
corporation.

                  "UNCONSOLIDATED INVESTMENT" means, as of any date, any
investment made by the Borrower or any Subsidiary in any other Person that,
pursuant to GAAP as in effect on such date, would not be consolidated with the
Borrower for financial reporting purposes immediately after giving effect to
such investment.

         2. Article 1 of the Credit Agreement is hereby amended by adding a new
Section 1.6 thereto as follows:

                  Section 1.6 HEALTHWELL

                           Notwithstanding anything to the contrary contained in
         any Loan Document, Healthwell and each subsidiary thereof:

                           (1) shall be deemed not to be a Subsidiary for any
                  purpose of any Loan Document, except with respect to (a) the
                  following defined terms: "ERISA Affiliate", and "Plan", and
                  (b) the following Sections of the Credit Agreement: 4.6, 4.9,
                  4.10, 6.1(a), 6.1(b), 6.1(c), 6.1(d), 6.1(h), 6.1(i), 6.2,
                  6.4, 6.6, 6.7, 6.14, 10.3 and 10.13, and
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                           (2) shall be deemed to be a Subsidiary for purposes
                  of Article 8(h) and 8(i) of the Credit Agreement, provided,
                  however, that any Event of Default that shall occur under
                  either Article 8(h) or 8(i) of the Credit Agreement solely as
                  a result of this Section 1.6 (X) shall not be treated as an
                  Event of Default for purposes of clause (B) of the last
                  paragraph of Article 8 of the Credit Agreement and (Y) shall
                  instead be treated as an Event of Default under clause (A) of
                  the last paragraph of Article 8 of the Credit Agreement.

         3. Section 7.4 of the Credit Agreement is hereby amended by (i)
deleting the word "and" at the end of paragraph (h) thereof, (ii) deleting the
period at the end of paragraph (i) thereof and by substituting in its place ";
and", and (iii) adding a new subsection (j) to read as follows:

              (j) Unconsolidated Investments.

         4. Section 7.5(d) of the Credit Agreement is hereby amended by
replacing the reference to "$20,000,000" with "$30,000,000".

         5. Section 7.5 of the Credit Agreement is hereby amended by (i)
deleting the word "and" at the end of paragraph (c) thereof, (ii) deleting the
period at the end of paragraph (d) thereof and by substituting in its place a
semicolon, and (iii) adding new subsections (e), (f) and (g) to read as follows:

                  (e) the issuance by Healthwell of shares of its common voting
         stock to Cayenta, Inc., at a subscription price of $1,250,000 in cash;

                  (f) the contribution of the Healthwell.com investment
         (previously acquired as part of New Hope Natural Media) to Healthwell,
         and sales, transfers, and other dispositions of the capital stock of
         Healthwell; and

                  (g) Unconsolidated Investments made or acquired pursuant to
         Section 7.4(j).

         6. The last paragraph of Article 8 of the Credit Agreement is hereby
amended and restated in its entirety to read as follows:

         (A) then, and in every such event (other than an event described in
         clause (h) or (i) of this Article), and at any time thereafter during
         the continuance of such event, the Administrative Agent may, and at the
         request of the Required Lenders shall, by notice to the Borrower, take
         either or both of the following actions, at the same or different
         times: (i) terminate the Revolving Commitments, and thereupon the
         Revolving Commitments shall terminate immediately and (ii) declare the
         Loans then outstanding to be due and payable in whole (or in part, in
         which case any principal not so declared to be due and payable may
         thereafter be declared to be due and payable), and thereupon the
         principal of the Loans so declared to be due and payable, together with
         accrued interest thereon and all fees and other obligations of each
         Loan Party accrued under the Loan Documents, shall become due and
         payable immediately, without presentment, demand, protest or other

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         notice of any kind, all of which are hereby waived by the Borrower; and
         (B) in case of any event described in clause (h) or (i) of this
         Article, the Revolving Commitments shall automatically terminate and
         the principal of the Loans then outstanding, together with accrued
         interest thereon and all fees and other obligations of each Loan Party
         accrued under the Loan Documents, shall automatically become due and
         payable, without presentment, demand, protest or other notice of any
         kind, all of which are hereby waived by the Borrower.

         7. Sections 1 - 6 of this Amendment shall not be effective until such
date (the "AMENDMENT EFFECTIVE DATE") as Required Lenders shall have consented
to the execution and delivery hereof by the Administrative Agent.

         8. On and as of the date hereof, the Borrower hereby (a) reaffirms and
admits the validity and enforceability of the Loan Documents and all of its
obligations thereunder, (b) agrees and admits that it has no defenses to or
offsets against any such obligation, (c) represents and warrants that no Event
of Default has occurred and is continuing, and that each of the representations
and warranties made by it in the Credit Agreement is true and correct with the
same effect as though such representation and warranty had been made on such
date, and (d) agrees to pay the reasonable fees and disbursements of Bryan Cave
LLP, special counsel to the Administrative Agent, in connection with this
Amendment.

         9. In all other respects (a) the Loan Documents shall remain in full
force and effect, (b) the Borrower's obligations under Section 3.3 shall be
unaffected by this Amendment, and (c) no amendment in respect of any term or
condition of any Loan Document contained herein shall be deemed to be an
amendment in respect of any other term or condition contained in any Loan
Document.

         10. This Amendment may be executed in any number of counterparts all of
which, taken together, shall constitute one Amendment. In making proof of this
Amendment, it shall only be necessary to produce the counterpart executed and
delivered by the party to be charged.

         11. THIS AMENDMENT IS BEING EXECUTED AND DELIVERED IN, AND IS INTENDED
TO BE PERFORMED IN, THE STATE OF NEW YORK AND SHALL BE CONSTRUED AND ENFORCEABLE
IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO
PRINCIPLES OF CONFLICT OF LAWS.

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                                 AMENDMENT NO. 1
                               PENTON MEDIA, INC.

         AS EVIDENCE of its agreement to the terms and conditions herein
contained, each of the undersigned has caused this Amendment to be executed on
its behalf.

                 PENTON MEDIA, INC.


                 By:
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                 Name:
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                 Title:
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                 THE BANK OF NEW YORK, as Administrative Agent


                 By:
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                 Name: Benjamin B. Todres
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                 Title:Vice President
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                 BANK OF AMERICA, N.A.


                 By:
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                 Name:
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                 Title:
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                 BANK ONE, NA (formerly known as First National Bank Of Chicago)


                 By:
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                 Name:
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                 Title:
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                                 AMENDMENT NO. 1
                               PENTON MEDIA, INC.


                       ALLFIRST BANK


                       By:
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                       Name:
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                       Title:
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                       BANK OF MONTREAL, CHICAGO BRANCH


                       By:
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                       Name:
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                       Title:
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                       BANKBOSTON, N.A.


                       By:
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                       Name:
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                       Title:
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                       CITY NATIONAL BANK


                       By:
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                       Name:
                             ---------------------------------------------------
                       Title:
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                       CREDIT AGRICOLE INDOSUEZ


                       By:
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                       Name:
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                       Title:
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                                 AMENDMENT NO. 1
                               PENTON MEDIA, INC.


                       DRESDNER BANK AG, NEW YORK AND GRAND CAYMAN BRANCHES

                       By:
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                       Name:
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                       Title:
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                       By:
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                       Name:
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                       Title:
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                       FLEET NATIONAL BANK


                       By:
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                       Name:
                             ---------------------------------------------------
                       Title:
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                       THE HUNTINGTON NATIONAL BANK


                       By:
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                       Name:
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                       Title:
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                       NATIONAL BANK OF CANADA


                       By:
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                       Name:
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                       Title:
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                       NATIONAL CITY BANK


                       By:
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                       Name:
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                       Title:
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                                 AMENDMENT NO. 1
                               PENTON MEDIA, INC.



                       PARIBAS


                       By:
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                       Name:
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                       Title:
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                       By:
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                       Name:
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                       Title:
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                       CITIZENS BANK OF MASSACHUSETTS

                       By:
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                       Name:
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                       Title:
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                       SUNTRUST BANK, CENTRAL FLORIDA, N.A.

                       By:
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                       Name:
                             ---------------------------------------------------
                       Title:
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                       VAN KAMPEN SENIOR INCOME TRUST


                       By:
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                       Name:
                             ---------------------------------------------------
                       Title:
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                       VAN KAMPEN SENIOR FLOATING RATE FUND


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