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                                                                    EXHIBIT 4.2

                  NON-NEGOTIABLE SUBORDINATED PROMISSORY NOTE

$3,000,000.00      Minneapolis, Minnesota
                   January 13, 1997

FOR VALUE RECEIVED, Nutrition Medical, Inc., a Minnesota corporation
("Maker"), promises to pay to Elan Pharma Inc., a Massachusetts corporation
("Payee"), in lawful money of the United States of America, the principal sum
of Three Million Dollars ($3,000,000), subject to reduction as provided
herein, together with interest in arrears on the unpaid principal balance at
an annual rate equal to three percent (3%) in the manner provided below.
Interest shall be calculated on the basis of a year of 365 or 366 days, as
applicable, and charged for the actual number of days elapsed.

This Note has been executed and delivered pursuant to and in accordance with
the terms and conditions of the Asset Purchase Agreement, dated as of January
13, 1997, by and between Maker and Payee (the "Agreement"), and is subject to
the terms and conditions of the Agreement, which are, by this reference,
incorporated herein and made a part hereof. Capitalized terms used in this
Note without definition shall have the respective meanings set forth in the
Agreement.

1. REDUCTION OF PRINCIPAL AMOUNT AND PAYMENTS

1.1     REDUCTION OF PRINCIPAL AMOUNT

The principal amount of the Note will be reduced, if applicable, as of the
fourth, fifth, sixth and seventh anniversaries of the Closing Date by amounts
calculated as follows:

(a)     by a dollar amount equal to the number of Shares sold by Payee during
the fourth year after the Closing Date multiplied by one half of a sum equal
to: (i) the average per share sales price for the Shares sold less (ii) Five
Dollars ($5.00);

(b)     by a dollar amount equal to the number of Shares sold by Payee during
the fifth year after the Closing Date multiplied by one half of a sum equal
to: (i) the average per share sales price for the Shares sold less (ii) Six
Dollars ($6.00);

(c)     by a dollar amount equal to the number of Shares sold by Payee during
the sixth year after the Closing Date multiplied by one half of a sum equal
to: (i) the average per share sales price for the Shares sold less (ii) Seven
Dollars ($7.00);

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(d)     by a dollar amount equal to the number of Shares sold by Payee during
the seventh year after the Closing Date multiplied by one half of a sum equal
to: (i) the average per share sales price for the Shares sold less (ii) Eight
Dollars ($8.00); and

(e)    by a dollar amount equal to the number of Shares held by Payee on the
seventh anniversary of the Closing Date multiplied by one half of a sum equal
to: (i) the stock price for a share of the common stock of the Maker on the
seventh anniversary of the Closing Date calculated as the average of the
closing prices for a share of the common stock of the Maker for the thirty
(30) days on which the stock was traded immediately preceding the seventh
anniversary of the Closing Date as reported for the market or exchange on
which the common stock was traded less (ii) Eight Dollars ($8.00).

(f)     if there shall be any change in the shares of the Maker's common
stock through merger, consolidation, reorganization, recapitalization, stock
dividend (of whatever amount), stock split or other change in the corporate
structure, appropriate adjustments shall be made in the dollar amount to be
deducted from amounts set forth in paragraphs 1.1(a)(ii), (b)(ii), (c)(ii),
(d)(ii) and (e)(ii).

For purposes of calculating any reductions, Payee will forward to Maker on
each anniversary date for which there is an applicable deduction its
calculation of the reduction and documentation to substantiate its sales
price for each sale. The sales price for purposes of the calculation shall be
the gross sales price before brokers' or other sales commissions and taxes or
other sales charges.

1.2     PRINCIPAL AND INTEREST

The principal amount of this Note shall be due and payable in full in a
single payment on January 12, 2004. Interest on the unpaid principal balance
of this Note shall be accrued annually and be added to the principal amount
of this Note on each anniversary of the date of this Note, including the
seventh anniversary.

1.3     MANNER OF PAYMENT

Payment of the principal on this Note shall be made by check at 2 Thurber
Road, Smithfield, Rhode Island, or at such other place in the United States
of America as Payee shall designate to Maker in writing or by wire transfer
of immediately available funds to a bank account in the United States
designated by Payee in writing. If payment of principal on this Note is due
on a day which is not a Business Day, such payment shall be due on the next
succeeding Business Day, and such extension of time shall be taken into
account in calculating the amount of interest payable under this Note.
"Business Day" means any day other than a Saturday, Sunday or legal holiday
in the State of Minnesota.

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1.4    PREPAYMENT

Maker may, without premium or penalty, at any time and from time to time,
prepay all or any portion of the outstanding principal balance due under this
Note, provided that each such prepayment is accompanied by accrued interest
on the amount of principal prepaid calculated to the date of such prepayment.
If all or any portion of this Note is prepaid, a calculation of the
reductions of the principal amount of the Note shall nevertheless be made
pursuant to Section 1.1, above, and on the seventh anniversary of this Note,
Payee shall reimburse Maker for the total amount of the reductions (but such
reimbursement shall not exceed the amount of the Note prepaid or otherwise
payable by the Maker).

1.5     RIGHT OF SET-OFF

Maker shall have the right to withhold and set-off against any amount due
hereunder the amount of any claim for indemnification or payment of damages
to which Maker may be entitled under the Agreement.

2. DEFAULTS

2.1     EVENTS OF DEFAULT

The occurrence of any one or more of the following events with respect to
Maker shall constitute an event of default hereunder ("Event of Default"):

(a)     If Maker shall fail to pay when due any payment of principal on this
Note and such failure continues for fifteen (15) days; PROVIDED, HOWEVER,
that the exercise by Maker in good faith of its right of set-off pursuant to
Section 1.5 above, whether or not ultimately determined to be justified,
shall not constitute an Event of Default.

(b)     If Maker fails to perform any other material obligation under the
Agreement and such failure continues for thirty (30) days after Payee
notifies Maker thereof in writing.

(c)      If, pursuant to or within the meaning of the United States
Bankruptcy Code or any other federal or state law relating to insolvency or
relief of debtors (a "Bankruptcy Law"), Maker shall (i) commence a voluntary
case or proceeding; (ii) consent to the entry of an order for relief against
it in an involuntary case; (iii) consent to the appointment of a trustee,
receiver, assignee, liquidator or similar official; (iv) make an assignment
for the benefit of its creditors; or (v) admit in writing its inability to
pay its debts as they become due.

(d)     If a court of competent jurisdiction enters an order or decree under
any Bankruptcy Law that (i) is for relief against Maker in an involuntary
case, (ii)

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appoints a trustee, receiver, assignee, liquidator or similar official for
Maker or substantially all of Maker's properties, or (iii) orders the
liquidation of Maker, and in each case the order or decree is not dismissed
within one hundred twenty (120) days.

(e)     The Maker shall make a Disposition of the Acquired Business.

2.2     NOTICE BY MAKER

Maker shall notify Payee in writing within ten (10) days after the occurrence
of any Event of Default of which Maker acquires knowledge.

2.3     REMEDIES

Upon the occurrence of an Event of Default hereunder (unless all Events of
Default have been cured or waived by Payee), Payee may, at its option, (i) by
written notice to Maker, declare the entire unpaid principal balance of this
Note, together with all accrued interest thereon, immediately due and payable
regardless of any prior forbearance, and (ii) exercise any and all rights and
remedies available to it under applicable law, including, without limitation,
the right to collect from Maker all sums due under this Note. Maker shall pay
all reasonable costs and expenses incurred by or on behalf of Payee in
connection with Payee's exercise of any or all of its rights and remedies
under this Note, including, without limitation, reasonable attorneys' fees.
If payment of all or any portion of this Note is accelerated or otherwise
collected by Payee pursuant to this Section 2.3 prior to the date on which
the principal amount of this Note would have been payable absent an Event of
Default, a calculation of the reductions of the principal amount of the Note
shall nevertheless be made pursuant to Section 1.1, above, and on the seventh
anniversary of this Note, Payee shall reimburse Maker for the total amount of
the reductions (but such reimbursement shall not exceed the amount of the
Note collected by Seller, or otherwise payable by, the Maker).

3. SUBORDINATION

(a)     Anything in this Note to the contrary notwithstanding, the obligations
of the Maker in respect of the principal, interest, fees and charges on this
Note shall be subordinate and junior in right of payment, to the extent and in
the manner hereinafter set forth, to all Debt. For purposes of this paragraph
3, "Debt" shall mean (i) all indebtedness for money borrowed, including,
without limitation, principal, interest accruing before and after any
Insolvency Event as defined below, premiums, penalties, fees or expenses, and
regardless of whether direct or indirect, now existing or hereafter arising,
absolute or contingent, secured or unsecured, or long or short term, under any
agreement entered into by the Maker after the date of this Note under which the
Maker incurs or guarantees any indebtedness for money borrowed, and (ii)
renewals, extensions, refundings, deferrals, restructurings, amendments and
modifications of the

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items described in (i) above; up to a maximum amount of Five Million
Dollars ($5,000,000).

(b)     In the event that the Maker makes a general assignment for the
benefit of creditors; or an order, judgment or decree is entered adjudicating
the Maker bankrupt or insolvent; or any order for relief with respect to the
Maker is entered under the Federal Bankruptcy Code; or the Maker petitions or
applies to any tribunal for the appointment of a custodian, trustee, receiver
or liquidator of the Maker or of any substantial part of the assets of the
Maker, or commences any proceeding relating to the Maker under any
bankruptcy, reorganization, arrangement, insolvency, readjustment of debt,
dissolution or liquidation law of any jurisdiction; or any such petition or
application is filed, or any such proceeding is commenced, against the Maker
and either (i) the Maker by any act indicates its approval thereof, consent
thereto or acquiescence therein or (ii) such petition, application or
proceeding is not dismissed within one hundred twenty (120) days
(collectively referred to as an "Insolvency Event"), or upon any acceleration
of Debt, then:

(i)     the holders of Debt shall be entitled to receive payment in full in
cash of all principal, premium, interest, fees and charges then due on all
Debt (including interest, fees and charges accruing thereon after the
commencement of any such proceedings) before the Payee is entitled to receive
any payment on account of principal, interest or other amounts due (or past
due) upon this Note, and the holders of Debt shall be entitled to receive for
application in payment thereof any payment or distribution of any kind or
character, whether in cash, property or securities or by set-off or
otherwise, which may be payable or deliverable in any such proceedings in
respect of this Note; and

(ii)    any payment or distribution of assets of the Maker, of any kind or
character, whether in cash, property or securities, to which the Payee would
be entitled except for the provisions of this paragraph 3(b) shall be paid or
delivered by the Maker directly to the holders of all Debt in the manner
provided in paragraph 3(e) below, for application in payment thereof until
all Debt (including interest, fees and charges accrued thereon after the date
of commencement of such proceedings) shall have been paid in full in cash.

(c)     Any amendment or modification of the terms of paragraph 3 of this
Note shall not be effective against any person or entity who was a holder of
Debt prior to or at the time of such amendment or modification unless such
holder of Debt so consents.

(d)     The holders of Debt may, at any time, in their discretion, renew,
amend, extend or otherwise modify the terms and provisions of Debt so held or
exercise any of their rights under the Debt including, without limitation, the
waiver of defaults thereunder and the amendment of any of the terms or
provisions thereof (or any notice evidencing

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or creating the same), all without notice to or assent from the Payee. No
compromise, alteration, amendment, renewal or other change of, or waiver,
consent or other action in respect of any liability or obligation under or in
respect of, any terms, covenants or conditions of the Debt (or any instrument
evidencing or creating the same), whether or not such release is in
accordance with the provisions of the Debt (or any instrument evidencing or
creating the same), shall in any way alter or affect any of the subordination
provisions of this Note.

(e)     If, notwithstanding the provisions of paragraph 3 of this Note, any
payment or distribution of any character (whether in cash, securities or
other property) or any security shall be received by the Payee in
contravention of this paragraph 3 before all the Debt shall have been paid in
full in cash, such payment, distribution or security shall be held in trust
for the benefit of, and shall be immediately paid over or delivered or
transferred to, the holders of Debt or their duly appointed agents for
application of payment according to the priorities of such Debt and ratably
among the holders of any class of Debt. Such payments received by the Payee
and delivered to the holders of the Debt shall be deemed not to be a payment
on this Note for any reason whatsoever and the indebtedness under this Note
shall remain as if such erroneous payment had never been paid by the Maker or
received by the Payee. In the event of the failure of the Payee to endorse or
assign any such payment, distribution or security, each holder of any Debt is
hereby irrevocably authorized to endorse or assign the same.

(f)     No present or future holder of Debt shall be prejudiced in its right
to enforce the provisions of paragraph 3 of this Note by any act or failure
to act on the part of the Maker.

(g)     If any payment or distribution to which Payee would otherwise have
been entitled but for the provisions of this paragraph 3 shall have been
applied, pursuant to the provisions of this paragraph 3, to the payment of
Debt, then and in such case and to such extent, the Payee (A) shall be
entitled to receive from the holders of such Debt at the time outstanding any
payments or distributions received by such holders of Debt in excess of the
amount sufficient to pay all Debt in full (whether or not then due and
whether such payment was in cash or such other form of consideration
acceptable to the holders of Debt in their sole discretion), (B) following
payment in full of the Debt (whether in cash or such other form of
consideration acceptable to the holders of Debt in their sole discretion),
shall be entitled to receive any and all further payments or distributions
applicable to Debt, and (C) following payment in full of the Debt (whether in
cash or such other form of consideration acceptable to the holders of Debt in
their sole discretion), shall be subrogated to the rights of the holders of
the Debt to receive distributions applicable to the Debt, in each case until
this Note shall have been paid in full in cash or such other consideration
acceptable to the Payee in its sole discretion. If the Payee has been
subrogated to the rights of the holders of Debt due to the operation of this
paragraph 3(g), the Maker agrees to take all such reasonable actions as are

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requested by Payee in order to cause Payee to be able to obtain payments from
the Maker with respect to such subrogation rights as soon as possible.

(h)     The provisions of this paragraph 3 are solely for the purpose of
defining the relative rights of the holders of Debt, on the one hand, and the
Payee on the other, against the Maker and its assets, and nothing herein is
intended to or shall impair, as between the Maker and the Payee, the
obligations of the Maker which are absolute and unconditional, to pay to the
holder the principal and interest on this Note as and when they become due
and payable in accordance with their terms, or is intended to or will affect
the relative rights of Payee and creditors of the Maker other than the
holders of the Debt, nor, except as provided in this paragraph 3, will
anything herein or therein prevent Payee from exercising all remedies
otherwise permitted by applicable law upon default under this Note, subject
to the rights, if any, under this paragraph 3 of the holders of Debt in
respect of cash, property or securities of the Maker received upon the
exercise of any such remedy and subject to this paragraph 3.

4. MISCELLANEOUS

4.1     WAIVER

The rights and remedies of Payee under this Note shall be cumulative and not
alternative. No waiver by Payee of any right or remedy under this Note shall
be effective unless in a writing signed by Payee. Neither the failure nor any
delay in exercising any right, power or privilege under this Note will
operate as a waiver of such right, power or privilege and no single or
partial exercise of any such right, power or privilege by Payee will preclude
any other or further exercise of such right, power or privilege or the
exercise of any other right, power or privilege. To the maximum extent
permitted by applicable law, (a) no claim or right of Payee arising out of
this Note can be discharged by Payee, in whole or in part, by a waiver or
renunciation of the claim or right unless in a writing, signed by Payee; (b)
no waiver that may be given by Payee will be applicable except in the
specific instance for which it is given; and (c) no notice to or demand on
Maker will be deemed to be a waiver of any obligation of Maker or of the
right of Payee to take further action without notice or demand as provided in
this Note. Maker hereby waives presentment, demand, protest and notice of
dishonor and protest.

4.2     NOTICES

Any notice required or permitted to be given hereunder shall be given
accordance with Section 11.05 of the Agreement.

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 4.3    SEVERABILITY

If any provision in this Note is held invalid or unenforceable by any court
of competent jurisdiction, the other provisions of this Note will remain in
full force and effect. Any provision of this Note held invalid or
unenforceable only in part or degree will remain in full force and effect to
the extent not held invalid or unenforceable.

4.4     GOVERNING LAW

This Note will be governed by the laws of the State of Minnesota without
regard to conflicts of laws principles.

4.5     PARTIES IN INTEREST

This Note shall bind Maker and its successors and assigns. This Note shall
not be assigned or transferred by Payee other than to a business in which
Payee owns more than one half of the equity and one half of the voting rights
without the express prior written consent of Maker, except by operation of
law. Payee shall promptly notify Maker of any such assignment, and the rights
of the assignee shall be subject to all the rights of Maker under the
Agreement.

4.6     SECTION HEADINGS, CONSTRUCTION

The headings of Sections in this Note are provided for convenience only and
will not affect its construction or interpretation. All references to
"Section" or "Sections" refer to the corresponding Section or Sections of
this Note unless otherwise specified.

All words used in this Note will be construed to be of such gender or number
as the circumstances require. Unless otherwise expressly provided, the words
"hereof" and "hereunder" and similar references refer to this Note in its
entirety and not to any specific section or subsection hereof.

IN WITNESS WHEREOF, Maker has executed and delivered this Note as of the date
first stated above.

NUTRITION MEDICAL, INC.

By:         /s/ William L. Rush
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Title:     President and Chief Executive Officer
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