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                                                                 Exhibit 10.45

                 FIRST AMENDMENT AND CONSENT TO CREDIT AGREEMENT

         THIS FIRST AMENDMENT AND CONSENT, dated as of April 17, 2003 (this
"AMENDMENT"), to the Credit Agreement, dated as of November 14, 2002 (as
amended, supplemented or otherwise modified from time to time, the "CREDIT
AGREEMENT"), by and among General Electric Capital Corporation, as Agent and
Lender ("AGENT"), Inverness Medical Innovations, Inc. ("INNOVATIONS"), Wampole
Laboratories, Inc. and Inverness Medical (UK) Holdings Limited, as borrowers
("BORROWERS"), the other Credit Parties signatory thereto, KeyBank National
Association, as documentation agent, and the lenders signatory thereto from time
to time (collectively, the "LENDERS").

                               W I T N E S S E T H

         WHEREAS, Borrowers have notified Agent that Innovations plans to
acquire one hundred percent (100%) of the issued and outstanding capital stock
of Ostex International, Inc., a Washington corporation ("OSTEX"), pursuant to
and in accordance with the terms and conditions set forth in that certain
Agreement and Plan of Merger, dated as of September 6, 2002, as amended by that
certain Amendment to Agreement and Plan of Merger, dated as of February 18, 2003
(in effect on the date hereof and with subsequent amendments as approved by
Agent in writing, the "MERGER AGREEMENT"), by and among Innovations, Geras
Acquisition Corp. ("GERAS") and Ostex (the "PROPOSED TRANSACTION");

         WHEREAS, Borrowers have requested that Agent and Requisite Lenders
consent to the Proposed Transaction on the terms and conditions set forth
herein; and

         WHEREAS, Agent and Requisite Lenders have agreed to amend the Credit
Agreement, in the manner, and on the terms and conditions, provided for herein;

         NOW THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt, adequacy and sufficiency of which are
hereby acknowledged, the parties hereto agree as follows:

         1. DEFINITIONS. Capitalized terms not otherwise defined herein shall
have the meanings ascribed to them in the Credit Agreement.

         2. AMENDMENT. As of the Effective Date (as hereinafter defined),
SECTION 6.1(V) of the Credit Agreement is hereby amended by deleting the
parenthetical therein and inserting the words ", including all transaction
costs, ordinary course trade payables, accrued expenses and unsecured
Indebtedness incurred, assumed or otherwise to be reflected on a consolidated
balance sheet of Borrowers and Target after giving effect to such Permitted
Acquisition" in lieu thereof and SECTION 6.2 of the Credit Agreement is hereby
amended by: (a) immediately following clause (e) of such SECTION 6.2, adding the
text "(f) US Borrower may make loans to, or investments in, Ostex following the
acquisition of one hundred percent (100%) of the capital stock of Ostex by
Innovations pursuant to the terms of that certain Agreement and Plan of Merger,
dated as of September 6, 2002, as amended, by and among Innovations, Geras and
Ostex; PROVIDED that the aggregate amount of such loans and/or investments
permitted by this clause (f) shall not exceed $7,000,000 at any time, unless
otherwise previously consented to by Requisite Lenders in writing"; and (b)
deleting the text "(f)" in each place where it appears in


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such SECTION 6.2 as in effect immediately prior to the Effective Date and
substituting in lieu thereof the text "(g)".

         3. CONSENT. As of the Effective Date, Agent and Requisite Lenders
hereby agree that the consummation of the Proposed Transaction on the terms and
conditions set forth in the Merger Agreement shall not create a breach under
SECTIONS 6.1 or 6.5 of the Credit Agreement, PROVIDED that:

              (a) Agent shall have received evidence satisfactory to Agent that
each of the conditions precedent to a Permitted Acquisition set forth in Section
6.1(i) - (xi) of the Credit Agreement (other than the conditions set forth in
Section 6.1(iv), (v), (vi) and (vii) which are hereby waived, PROVIDED that (i)
the Credit Parties do not expend any cash in connection with the Proposed
Transaction other than payments to Ostex which are permitted under Section
6.2(d) or (f) and $900,000 for costs and expenses and (ii) all Indebtedness,
Guaranteed Indebtedness, contingent obligations and other liabilities (other
than ordinary course trade payables) incurred, assumed or otherwise reflected on
the consolidated balance sheet of Borrowers and Ostex after giving effect to
such Proposed Transaction are paid, and all Liens (other than Permitted
Encumbrances) on the assets and Stock of Ostex are terminated, concurrently with
the consummation of the Proposed Transaction) have been satisfied in connection
with the Proposed Transaction, the Agent acknowledging that as of the Effective
Date, the Credit Parties have satisfied the conditions set forth in Section
6.1(i) and (ix)(1) and (2) of the Credit Agreement;

              (b) Agent shall have received (i) an Assumption and Affirmation
Agreement, in form and substance satisfactory to Agent (the "ASSUMPTION
AGREEMENT"), pursuant to which Ostex expressly agrees to be bound by all of the
Loan Documents to which Geras is a party immediately prior to giving effect to
the Proposed Transaction as if Ostex were a party to such Loan Documents as an
original signatory thereof; (ii) a Counterpart to Intellectual Property Security
Agreement, in the form of EXHIBIT A to the US Intellectual Property Security
Agreement, together with updated SCHEDULES I, II and/or III to such US
Intellectual Property Security Agreement, as applicable, which schedules shall
include the Intellectual Property of Ostex; and (iii) an Amendment to the US
Pledge Amendment, in form and substance satisfactory to Agent, pursuant to which
SCHEDULE I to such US Pledge Agreement is amended to include the pledge by
Innovations of one hundred percent (100%) of the issued and outstanding capital
stock of Ostex (the "OSTEX STOCK") to Agent, in each case duly executed and
delivered by an authorized officer of Ostex and/or Innovations, as applicable;

              (c) Agent shall have received an original stock certificate
representing the Ostex Stock, together with stock powers duly executed in blank,
pledged by Innovations pursuant to the terms of the US Pledge Agreement;

              (d) Agent shall have received evidence satisfactory to Agent that
Agent (for the benefit of itself and Lenders) has a valid and perfected first
priority security interest in all of the Collateral (subject to Permitted
Encumbrances) owned by Ostex to secure all of the Obligations, including (i)
such documents duly executed by Ostex (including financing statements or
amendments thereto under the Code and blocked account agreements with all
deposit banks with whom Ostex has maintained a deposit account) as Agent may
request in order to perfect its security interests in such Collateral and (ii)
copies of Code search reports listing all


                                       2

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effective financing statements that names Ostex as debtor, together with copies
of such financing statements, none of which shall cover the Collateral;

              (e) Borrowers shall use commercially reasonable best efforts to
obtain and deliver to Agent landlord waivers, in form and substance reasonably
satisfactory to Agent, duly executed and delivered by the lessors of each of the
properties leased by Ostex located at (i) Park 90/5, Buildings A and D, Seattle,
Washington 98108, and (ii) 5955 Airport Way South, Seattle, Washington 98108;
PROVIDED that if Borrowers are unable to deliver to Agent a landlord waiver for
any such location on or prior to the consummation of the Proposed Transaction,
then (A) within thirty (30) days after the consummation of the Proposed
Transaction, Ostex shall send copies of all books and records kept at such
location to another location for which the Borrowers have previously delivered
to Agent a landlord waiver, in form and substance satisfactory to Agent, (B)
within ninety (90) days after the consummation of the Proposed Transaction,
Ostex shall move all books and records kept at such location to another location
for which the Borrowers have previously delivered to Agent a landlord waiver, in
form and substance satisfactory to Agent, (C) within eight (8) months after the
consummation of the Proposed Transaction, Ostex shall move all Collateral at
such location to another location for which the Borrowers have previously
delivered to Agent a landlord waiver, in form and substance satisfactory to
Agent, and (D) no Credit Party shall transfer or move any Inventory or other
Collateral having, individually or in the aggregate, a resale value in excess of
$200,000 to such location without the Agent's prior written consent or until
Ostex shall have delivered to the Agent a Landlord Waiver with respect to such
location.

              (f) Within thirty (30) days after the consummation of the Proposed
Transaction, Agent shall have received tri-party blocked account agreements, in
form and substance reasonably satisfactory to Agent, duly executed and delivered
by Ostex and (i) U.S. Bank, (ii) Commerce Bank of Washington and (iii) Copper
Mountain Trust, as the case may be, in each case in accordance with the
requirements set forth in SECTION 1.8 and ANNEX C of the Credit Agreement;

              (g) Agent shall have received (x) updated SCHEDULES 3.1, 3.2, 3.6,
3.7, 3.8, 3.15, 3.19 and 5.1 to the Credit Agreement and (x) a revised EXHIBIT
A-2 updated to include Material Contracts to which Ostex is a party, each in
form and substance satisfactory to Agent, after giving pro forma effect to the
Proposed Transaction;

              (h) Agent shall have received a copy of Ostex's (i) charter
documents and all amendments thereto, (ii) good standing certificate in its
jurisdiction of incorporation and (iii) good standing certificates or the
foreign equivalent (including verification of tax status) and certificates of
qualification to conduct business in each jurisdiction where its ownership or
lease of property or the conduct of its business requires such qualification,
each dated a recent date and certified by the applicable Secretary of State or
other authorized Governmental Authority;

              (i) Agent shall have received a copy of Ostex's (i) bylaws and all
amendments thereto and (ii) resolutions of Ostex's Board of Directors and, to
the extent required under applicable law, stockholders, approving and
authorizing the execution, delivery and performance of the Merger Agreement and
the Loan Documents to which such Person is a party and the transactions to be
consummated in connection therewith, each certified by Ostex's


                                       3

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corporate secretary or an assistant secretary (after giving effect to the
Proposed Transaction) as being in full force and effect without any modification
or amendment;

              (j) Agent shall have received a copy of Innovations' and Geras'
(i) bylaws and all amendments thereto and (ii) resolutions of such Person's
Board of Directors and, to the extent required under applicable law,
stockholders, approving and authorizing the execution, delivery and performance
of the Merger Agreement and the Loan Documents to which such Person is a party
and the transactions to be consummated in connection therewith, each certified
by such Person's corporate secretary or an assistant secretary (after giving
effect to the Proposed Transaction) as being in full force and effect without
any modification or amendment;

              (k) Agent shall have received a signature and incumbency
certificate of the officers of Ostex, certified by Ostex's corporate secretary
or an assistant secretary (after giving effect to the Proposed Transaction) as
being true, accurate, correct and complete in all respects;

              (l) Agent shall have received executed copies of the Merger
Agreement, together with all amendments thereto, and all documentation delivered
in connection therewith, certified by the Vice President and Chief Operating
Officer of Innovations to be true and complete and in full force and effect as
of the Effective Date;

              (m) Agent shall have received a legal opinion of counsel
acceptable to Agent which shall provide (i) that Agent's Lien on the Collateral,
as such Lien shall be assumed and affirmed by Ostex pursuant to the Assumption
Agreement shall, after giving effect to the Proposed Transaction, continue in
full force and effect and shall continue to have the priority contemplated by
this Credit Agreement and the other Loan Documents, (ii) that the Proposed
Transaction was approved by all requisite corporate action by Innovations and
Geras and (iii) such other opinions as Agent may reasonably request, all in form
and substance satisfactory to Agent; and

              (n) The Proposed Transaction shall have been consummated on or
prior to June 30, 2003.

         4. REPRESENTATIONS AND WARRANTIES. To induce Agent and Requisite
Lenders to enter into this Amendment, the Credit Parties hereby, jointly and
severally, represent and warrant that:

              (a) The execution, delivery and performance by Ostex and each
Credit Party of the Merger Agreement and any Loan Documents to which it is a
party and the creation of all Liens provided for therein: (i) are within such
Person's corporate, company or partnership power; (ii) have been duly authorized
by all necessary corporate, limited liability company or limited partnership
action; (iii) do not contravene any provision of such Person's charter, bylaws
or equivalent constitutive documents or partnership or operating agreement, as
applicable; (iv) do not violate any law or regulation, or any order or decree of
any court or Governmental Authority; (v) do not conflict with or result in the
breach or termination of, constitute a default under or accelerate or permit the
acceleration of any performance required by, any indenture,


                                       4

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mortgage, deed of trust, lease, agreement or other instrument to which such
Person is a party or by which such Person or any of its property is bound; (vi)
do not result in the creation or imposition of any Lien upon any of the property
of such Person; and (vii) do not require the consent or approval of any
Governmental Authority or any other Person except those which will have been
duly obtained, made or complied with prior to the Effective Date.

              (b) This Amendment has been duly executed and delivered by or on
behalf of each of the Credit Parties.

              (c) This Amendment constitutes a legal, valid and binding
obligation of each of the Credit Parties, enforceable against each of them in
accordance with its terms.

              (d) No Default or Event of Default has occurred and is continuing
after giving effect to this Amendment.

              (e) No action, claim or proceeding is now pending or, to the
knowledge of any Credit Party, threatened against such Credit Party, at law, in
equity or otherwise, before any court, board, commission, agency or
instrumentality of any foreign, federal, state, or local government or of any
agency or subdivision thereof, or before any arbitrator or panel of arbitrators,
which (i) challenges any Credit Party's right or power to enter into or perform
any of its obligations under this Amendment, the Merger Agreement, the Credit
Agreement and the other Loan Documents to which it is a party, or the validity
or enforceability of this Amendment, the Merger Agreement, the Credit Agreement
or any Loan Document or any action taken thereunder, or (ii) has a reasonable
risk of being determined adversely to any Credit Party and that, if so
determined, could reasonably be expected to have a Material Adverse Effect after
giving effect to this Amendment.

              (f) The representations and warranties of Ostex and the Credit
Parties contained in the Merger Agreement, the Credit Agreement and each other
Loan Document shall be true and correct in all material respects on and as of
(i) the Effective Date and (ii) the date the Proposed Transaction is consummated
(both before and after giving effect to the Proposed Transaction), in each case,
with the same effect as if such representations and warranties had been made on
and as of such date, except that any such representation or warranty which is
expressly made only as of a specified date need be true only as of such date.

              (g) No information contained in the Merger Agreement or any
document furnished in connection with the Merger Agreement (including, without
limitation, the proxy statement and any other information furnished to
shareholders of Ostex) contains or will contain any untrue statement of a
material fact or omits or will omit to state a material fact necessary to make
the statements contained therein not misleading in light of the circumstances
under which they were made.

         5. NO OTHER AMENDMENTS/WAIVERS. Except as expressly provided herein,
(a) the Credit Agreement shall be unmodified and shall continue to be in full
force and effect in accordance with its terms and (b) this Amendment shall not
be deemed a waiver of any term or condition of any Loan Document and shall not
be deemed to prejudice any right or rights which Agent or any Lender may now
have or may have in the future under or in connection with any


                                       5

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Loan Document or any of the instruments or agreements referred to therein, as
the same may be amended from time to time.

         6. OUTSTANDING INDEBTEDNESS; WAIVER OF CLAIMS. Each of Borrowers and
other Credit Parties hereby acknowledges and agrees that as of April 9, 2003,
(a) the aggregate outstanding principal amount of the European Revolving Loan is
$22,960,000, (b) the aggregate outstanding principal amount of the US Term Loan
is $20,000,000, and (c) the aggregate outstanding principal amount of the
European Term Loan is $9,975,000, and that such principal amount is payable
pursuant to the Credit Agreement without defense, offset, withholding,
counterclaim or deduction of any kind. Borrowers and each other Credit Party
hereby waives, releases, remises and forever discharges Agent, Lenders and each
other Indemnified Person from any and all claims, suits, actions,
investigations, proceedings or demands arising out of or in connection with the
Credit Agreement (collectively, "CLAIMS"), whether based in contract, tort,
implied or express warranty, strict liability, criminal or civil statute or
common law of any kind or character, known or unknown, which any Borrower or any
other Credit Party ever had, now has or might hereafter have against Agent or
Lenders which relates, directly or indirectly, to any acts or omissions of
Agent, Lenders or any other Indemnified Person on or prior to the Effective
Date, PROVIDED, that no Borrower nor any other Credit Party waives any Claim
solely to the extent such Claim relates to Agent's or any Lender's gross
negligence or willful misconduct.

         7. EXPENSES. Borrowers hereby reconfirm their obligations pursuant to
SECTION 11.3 of the Credit Agreement to pay and reimburse Agent for all
reasonable costs and expenses (including, without limitation, reasonable fees of
counsel) incurred in connection with the negotiation, preparation, execution and
delivery of this Amendment and all other documents and instruments delivered in
connection herewith.

         8. CONSENT FEE. Borrowers will pay a non-refundable consent fee to
Agent, for the ratable benefit of each Lender who executes a counterpart
signature page to this Amendment and returns such signature page to Agent by not
later than 5 p.m. (EST) on April 17, 2003, in an amount equal to the product of
each such Lender's Commitment multiplied by 0.30% (the "CONSENT FEE"), such
Consent Fee being fully earned on the Effective Date.

         9. EFFECTIVENESS. This Amendment shall become effective as of the date
hereof (the "EFFECTIVE DATE") only upon satisfaction in full in the judgment of
Agent of each of the following conditions:

              (a) AMENDMENT. Agent shall have received six (6) original
signature pages to this Amendment, duly executed and delivered by Agent,
Requisite Lenders and each of the Credit Parties.

              (b) CONSENT FEE; PAYMENT OF EXPENSES. Borrowers shall have paid to
Agent (i) the Consent Fee and (ii) all costs, fees and expenses owing in
connection with this Amendment and the other Loan Documents and due to Agent
(including, without limitation, reasonable legal fees and expenses).


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              (c) REPRESENTATIONS AND WARRANTIES. The representations and
warranties of or on behalf of each of the Credit Parties in this Amendment shall
be true and correct on and as of the Effective Date.

         10. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND INTERPRETED
IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

         11. COUNTERPARTS. This Amendment may be executed by the parties hereto
on any number of separate counterparts and all of said counterparts taken
together shall be deemed to constitute one and the same instrument.

         12. CONSENT TO AMENDMENT TO SCHEDULES TO CREDIT AGREEMENT. Each of the
Requisite Lenders hereby consents to the amendments to the Schedules to the
Credit Agreement referred to in SECTION 3(g) of this Amendment.


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                  IN WITNESS WHEREOF, this Amendment has been duly executed as
of the date first written above.

                            INVERNESS MEDICAL INNOVATIONS, INC.

                            By:  /S/ ANTHONY J. BERNARDO
                                 ------------------------
                            Name:  Anthony J. Bernardo
                            Title: Vice President and Chief Operating Officer



                            WAMPOLE LABORATORIES, INC.

                            By:  /S/ ANTHONY J. BERNARDO
                                 ------------------------
                            Name:  Anthony J. Bernardo
                            Title: Vice President and Chief Operating Officer



                            INVERNESS MEDICAL (UK) HOLDINGS LIMITED

                            By:  /S/ ANTHONY J. BERNARDO
                                 ------------------------
                            Name:  Anthony J. Bernardo
                            Title: Authorized Signer



                            GENERAL ELECTRIC CAPITAL
                            CORPORATION, as Agent and Lender

                            By: /S/ JAY SEPANSKI
                                ----------------------------------------
                                   Duly Authorized Signatory



                            KEYBANK NATIONAL ASSOCIATION, as Documentation
                            Agent and Lender

                            By: /S/ CARLTON WILLIAMS
                                ----------------------------------------
                                     Duly Authorized Signatory


                            THE ROYAL BANK OF SCOTLAND PLC, as Lender


                            By: /S/ ANDREW S. WEINBERG
                                -----------------------
                            Name: Andrew S. Weinberg
                            Title: Senior Vice President


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The following Persons are signatories to this Amendment in their capacity as
Credit Parties and not as Borrowers.


                    SELFCARE TECHNOLOGY, INC.

                    By:  /S/ DUANE L. JAMES
                         -------------------
                    Name:  Duane L. James
                    Title: Treasurer



                    INVERNESS MEDICAL, INC.

                    By:  /S/ ANTHONY J. BERNARDO
                         ------------------------
                    Name: Anthony J. Bernardo
                    Title:  President



                    UNIPATH DIAGNOSTICS, INC.

                    By:  /S/ ANTHONY J. BERNARDO
                         ------------------------
                    Name:  Anthony J. Bernardo
                    Title: Vice President and
                           Chief Operating Officer



                    UNIPATH ONLINE, INC.

                    By:  /S/ ANTHONY J. BERNARDO
                         ------------------------
                    Name: Anthony J. Bernardo
                    Title:  President



                    GERAS ACQUISITION CORP.

                    By:  /S/ ANTHONY J. BERNARDO
                         ------------------------
                    Name: Anthony J. Bernardo
                    Title:  President


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                    INVERNESS MEDICAL INTERNATIONAL HOLDING CORP.

                    By:  /S/ DUANE L. JAMES
                         -------------------
                    Name:  Duane L. James
                    Title: Treasurer



                    INVERNESS MEDICAL INTERNATIONAL HOLDING CORP. II

                    By:  /S/ DUANE L. JAMES
                         -------------------
                    Name:  Duane L. James
                    Title: Treasurer



                    ORGENICS INTERNATIONAL HOLDINGS BV

                    By:  /S/ PAUL T. HEMPEL
                         ------------------------
                    Name:  Paul T. Hempel
                    Title: Director



                    INVERNESS MEDICAL SWITZERLAND GMBH

                    By:  /S/ PAUL T. HEMPEL
                         ------------------------
                    Name:  Paul T. Hempel
                    Title: Gescha fts fuhrer



                    UNIPATH DIAGNOSTICS GMBH

                    By:  /S/ PAUL T. HEMPEL
                         ------------------------
                    Name:  Paul T. Hempel
                    Title: Authorized Signer


<PAGE>

                    UNIPATH LIMITED

                    By:  /S/ ANTHONY J. BERNARDO
                         ------------------------
                    Name: Anthony J. Bernardo
                    Title:  Authorized Signer



                    CAMBRIDGE DIAGNOSTICS IRELAND LIMITED

                    By:  /S/ PAUL T. HEMPEL
                         ------------------------
                    Name:  Paul T. Hempel
                    Title: Director