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                                                                   Exhibit 10.47

                               FIRST AMENDMENT TO
                    SUBORDINATED CONVERTIBLE PROMISSORY NOTES

         This First Amendment to Subordinated Convertible Promissory Notes (this
"AMENDMENT") is entered into as of January 15, 2004 by and between Inverness
Medical Innovations, Inc., a Delaware corporation (the "BORROWER") and the
lenders whose names are set forth on the signature pages hereto (the "LENDERS").

                                    RECITALS

         WHEREAS, the Borrower, the Lenders and certain other parties entered
into that certain Subordinated Note and Warrant Purchase Agreement dated as of
September 20, 2002 (the "PURCHASE AGREEMENT").

         WHEREAS, pursuant to the Purchase Agreement, the Borrower issued
Subordinated Convertible Promissory Notes, dated September 20, 2002 (the
"NOTES"), in an aggregate principal amount of $6 million to the Lenders.

         WHEREAS, the Borrower entered into that certain Credit Agreement, dated
as of November 14, 2002, among the Borrower, Wampole Laboratories, Inc.,
Inverness Medical (UK) Holdings Limited, General Electric Capital Corporation,
as administrative agent, Keybank National Association, as documentation agent,
GECC Capital Markets Group, Inc., as lead arranger, and certain other credit
parties and lenders signatory thereto (the "CREDIT AGREEMENT").

         WHEREAS, the Credit Agreement was amended and restated as of August 27,
2003 in connection with the Borrower's acquisition of Applied Biotech, Inc.
("ABI"), and the Borrower incurred an additional $13.4 million of indebtedness
under the Credit Agreement, as amended and restated, to finance the Borrower's
acquisition of ABI.

         WHEREAS, the Credit Agreement, as previously amended and restated, was
amended and restated as of September 30, 2003 in connection with the Borrower's
acquisition of certain assets relating to several product lines of Abbott
Laboratories (the "ABBOTT ASSETS"), and the Borrower incurred an additional
$55.0 million of indebtedness under the Credit Agreement, as amended and
restated, to finance the Borrower's acquisition of these assets.

         WHEREAS, the $68.4 million of indebtedness incurred by the Borrower to
finance the acquisitions of ABI and the Abbott Assets constitutes "Senior
Obligations" within the meaning of Section 3(a)(iv)(B) of the Notes.

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         WHEREAS, the Borrower may enter into one or more new debt transactions
whereby it would repay some or all of its outstanding indebtedness under the
Credit Agreement, as amended and restated, using the net proceeds from the new
debt transactions.

         WHEREAS, the Lenders together hold at least sixty-six and two-thirds
percent (66 2/3%) of the aggregate principal amount outstanding under the Notes.

         WHEREAS, the Borrower and the Lenders desire to amend the Notes in
order to reflect their intention that the term "Senior Obligations" under the
Notes includes indebtedness incurred to redeem, repay or refinance indebtedness
constituting Senior Obligations within the meaning of Section 3(a)(iv)(B) of the
Notes.

         WHEREAS, all capitalized terms used but not defined in this Amendment
shall have the meanings ascribed to such terms in the Notes.

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the foregoing and the respective
representations, warranties, covenants and agreements set forth in this
Amendment, and intending to be legally bound, the Borrower and the Lenders
hereby agree as follows:

                              SECTION 1. AMENDMENT

         1.1.     Clause (A) of the first sentence of Section 3(a)(iv) of each
of the Notes that currently reads as follows:

                  "[The term "Senior Obligations" shall mean] (A) all principal
                  of, and premium and interest on, and all other amounts owing
                  or guaranteed by the Borrower or any of its subsidiaries in
                  respect of, any indebtedness incurred or guaranteed by the
                  Borrower or any of its subsidiaries for money borrowed from
                  any bank or other institutional lender now or hereafter
                  outstanding or hereafter incurred (including without
                  limitation all indebtedness incurred or guaranteed by the
                  Borrower or any of its subsidiaries to. . ."

is amended such that clause (A) of the first sentence of Section 3(a)(iv) of
each of the Notes reads as follows:

                  "[The term "Senior Obligations" shall mean] (A) all principal
                  of, and premium and interest on, and all other amounts owing
                  or guaranteed by the Borrower in respect of, any indebtedness
                  incurred or guaranteed by the Borrower for money borrowed from
                  any lender now or hereafter outstanding or hereafter incurred
                  (including without limitation all indebtedness incurred or
                  guaranteed by the Borrower to . . ."

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         1.2.     Clause (B) of the first sentence of Section 3(a)(iv) of each
of the Notes that currently reads as follows:

                  "[The term "Senior Obligations" shall mean]. . . (B) any
                  indebtedness of the Borrower incurred to finance the
                  Borrower's acquisition (by merger, consolidation, stock
                  purchase or otherwise) of a Person or the Borrower's
                  acquisition of all or substantially all of the assets of a
                  Person or all or substantially all of the assets of a division
                  or line of business of a Person."

is amended and restated such that clause (B) of the first sentence of Section
3(a)(iv) of each of the Notes reads as follows:

                  "[The term "Senior Obligations" shall mean]. . . (B) (i) any
                  indebtedness of the Borrower incurred after September 20, 2002
                  to finance the Borrower's acquisition (by merger,
                  consolidation, stock purchase or otherwise) of a Person or the
                  Borrower's acquisition of all or substantially all of the
                  assets of a Person or all or substantially all of the assets
                  of a division or line of business of a Person and (ii) any
                  indebtedness of the Borrower incurred to redeem, repay or
                  refinance any indebtedness described in clause (i) above or
                  this clause (ii)."

         1.3.     All other terms and conditions of the Notes shall be unchanged
and remain in full force and effect.

         1.4.     Pursuant and subject to the provisions of Section 9 of the
Notes, the Lenders hereby consent to the amendments set forth in Sections 1.1
and 1.2 of this Amendment and, for the avoidance of doubt, acknowledge that such
amendment is intended to apply to all of the Notes, not only the Notes held by
the Lenders.

              SECTION 2. REPRESENTATIONS, WARRANTIES AND COVENANTS

         2.1.     REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE BORROWER. The
Borrower represents and warrants to, and covenants with, the Lenders that (i)
the Borrower has full right, power, authority and capacity to enter into this
Amendment and has taken all necessary action to authorize the execution,
delivery and performance of this Amendment, (ii) the Borrower is duly organized,
validly existing and in good standing under the laws of the State of Delaware,
and (iii) upon the execution and delivery of this Amendment, this Amendment
shall constitute a valid and binding obligation of the Borrower enforceable in
accordance with its terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, reorganization, moratorium or similar laws affecting
creditors' and contracting parties' rights generally and except as
enforceability may be subject to general principles of equity (regardless of
whether such enforceability is considered in a proceeding in equity or at law).

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         2.2.     REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE LENDERS. Each
Lender represents and warrants to, and covenants with, the Borrower that (i)
such Lender has full right, power, authority and capacity to enter into this
Amendment and has taken all necessary action to authorize the execution,
delivery and performance of this Amendment, (ii) if such Lender is an entity,
such Lender is duly organized, validly existing and in good standing under the
laws of its jurisdiction of organization, and (iii) upon the execution and
delivery of this Amendment, this Amendment shall constitute a valid and binding
obligation of such Lender enforceable in accordance with its terms, except as
enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' and contracting
parties' rights generally and except as enforceability may be subject to general
principles of equity (regardless of whether such enforceability is considered in
a proceeding in equity or at law).

                            SECTION 3. MISCELLANEOUS

         3.1.     EFFECTIVENESS. This Amendment is subject to, and will only
become effective upon, the Borrower obtaining the prior written consent of the
Senior Agent, as defined in the Subordination Agreement, to this Amendment. The
Borrower will notify the Lenders of the date on which this Amendment becomes
effective.

         3.2.     GOVERNING LAW. This Amendment shall be governed by, and
construed and enforced in accordance with, the substantive laws of The
Commonwealth of Massachusetts without regard to its principles of conflicts of
laws. Any dispute arising out of or relating to this Amendment shall be filed
and prosecuted in any court of competent subject matter jurisdiction located in
Massachusetts. The Borrower and the Lenders hereby consent to the personal
jurisdiction of such courts over them, stipulate to the convenience, fairness
and efficiency of proceeding in such courts, and covenant not to assert any
objection to proceeding in such courts based on any alleged lack of jurisdiction
or any alleged inconvenience, unfairness or inefficiency of such courts.

         3.3.     COUNTERPARTS. This Amendment may be executed in multiple
counterparts, each of which shall constitute an original but all of which shall
constitute but one and the same instrument. One or more counterparts of this
Amendment may be delivered via facsimile transmission, with the intention that
they shall have the same effect as an original counterpart hereof.

         3.4.     COMPLETE AGREEMENT. This Amendment, together with the Notes,
as amended by this Amendment, constitutes the entire contract among the parties
relating to the subject matter hereof and supersedes any and all previous
agreements and understandings, oral or written, relating to the subject matter
hereof. Without limiting and in furtherance of Section 1.3 above, the Notes, as
specifically amended by this Amendment, are and shall continue to be in full
force and effect and are hereby in all respects ratified and confirmed.

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

                            BORROWER:

                            INVERNESS MEDICAL INNOVATIONS, INC.


                            By: /s/  Ron Zwanziger
                                --------------------------------------
                              Name:
                              Title:

                            LENDERS:

                            PERRY PARTNERS, L.P.

                            By: Perry Corp., Managing General Partner

                            By: /s/  Randall Borkenstein
                              ----------------------------------------
                              Name:   Randall Borkenstein
                              Title: Managing Director and Chief Financial
                                     Officer

                            PERRY PARTNERS INTERNATIONAL, INC.

                            By:  Perry Corp., Investment Manager


                            By: /s/  Randall Borkenstein
                                --------------------------------------
                              Name:   Randall Borkenstein
                              Title: Managing Director and Chief Financial
                                      Officer

                            ZWANZIGER FAMILY VENTURES, LLC


                            By:  /s/  Ron Zwanziger
                                --------------------------------------
                                Name:
                                Title:

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