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                                  UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549


                                    FORM 8-K

                 CURRENT REPORT PURSUANT TO SECTION 13 OR 15 (d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934



       Date of Report (Date of earliest event reported) December 29, 1999





                         NOVAMETRIX MEDICAL SYSTEMS INC.
             (Exact name of registrant as specified in its charter)






                                                                               
                          Delaware                          20-8969                       06-0977422
               (State or other jurisdiction            (Commission File               (I.R.S. Employer
           of incorporation or organization)                 Number)                 Identification No.)






                5 Technology Drive Wallingford, Connecticut 06492
               (Address of principal executive offices) (Zip Code)



       Registrant's telephone number, including area code: (203) 265-7701


                                 Not Applicable
          (Former name or former address, if changed since last report)
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ITEM 5.  OTHER EVENTS

                  On December 15, 1999, the Board of Directors of Novametrix
Medical Systems Inc. (the "Company") declared a dividend of one preferred share
purchase right (a "Right") for each outstanding share of common stock, $.01 par
value (the "Common Shares"), of the Company. The dividend is payable on December
30, 1999 (the "Record Date") to the stockholders of record on that date. Each
Right entitles the registered holder to purchase from the Company one
one-hundredth of a share of Series A Preferred Stock, $1.00 par value (the
"Preferred Shares"), of the Company, at a price of $25.00 per one one-hundredth
of a Preferred Share (the "Purchase Price"), subject to adjustment. The
description and terms of the Rights are set forth in a Rights Agreement (the
"Rights Agreement") between the Company and ChaseMellon Shareholder Services,
L.L.C., as Rights Agent (the "Rights Agent").

                  Until the earlier to occur of (i) 10 days following a public
announcement that a person or group of affiliated or associated persons (an
"Acquiring Person") have acquired beneficial ownership of 20% or more of the
outstanding Common Shares or (ii) 10 days (or such later date as may be
determined by action of the Board of Directors prior to such time as any person
becomes an Acquiring Person) following the commencement of, or announcement of
an intention to make, a tender offer or exchange offer the consummation of which
would result in the beneficial ownership by a person or group of 20% or more of
such outstanding Common Shares (the earlier of such dates being called the
"Distribution Date"), the Rights will be evidenced, with respect to any of the
Common Share certificates outstanding as of the Record Date, by such Common
Share certificate with a copy of a Summary of Rights attached thereto.

                  The Rights Agreement provides that, until the Distribution
Date, the Rights will be transferred with and only with the Common Shares. Until
the Distribution Date (or earlier redemption or expiration of the Rights), new
Common Share certificates issued after the Record Date, upon transfer or new
issuance of Common Shares will contain a notation incorporating the Rights
Agreement by reference. Until the Distribution Date (or earlier redemption or
expiration of the Rights), the surrender for transfer of any certificates for
Common Shares, outstanding as of the Record Date, even without such notation or
a copy of the Summary of Rights being attached thereto, will also constitute the
transfer of the Rights associated with the Common Shares represented by such
certificate. As soon as practicable following the Distribution Date, separate
certificates evidencing the Rights ("Rights Certificates") will be mailed to
holders of record of the Common Shares as of the close of business on the
Distribution Date and such separate Rights Certificates alone will evidence the
Rights.

                  The Rights are not exercisable until the Distribution Date.
The Rights will expire on December 15, 2009 (the "Final Expiration Date"),
unless the Final Expiration Date is extended or unless the Rights are earlier
redeemed by the Company, in each case, as described below.

                  The Purchase Price payable, and the number of Preferred Shares
or other securities or property issuable, upon exercise of the Rights are
subject to adjustment from time to time to prevent dilution (i) in the event of
a stock dividend on, or a subdivision, combination or reclassification of, the
Preferred Shares, (ii) upon the grant to holders of the Preferred Shares of
certain rights or warrants to subscribe for or purchase Preferred Shares at a
price, or securities


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convertible into Preferred Shares with a conversion price, less than the then
current market price of the Preferred Shares or (iii) upon the distribution to
holders of the Preferred Shares of evidences of indebtedness or assets
(excluding regular periodic cash dividends paid out of earnings or retained
earnings or dividends payable in Preferred Shares) or of subscription rights or
warrants (other than those referred to above).

                  The number of outstanding Rights and the number of one
one-hundredths of a Preferred Share issuable upon exercise of each Right are
also subject to adjustment in the event of a stock split of the Common Shares or
a stock dividend on the Common Shares payable in Common Shares or subdivisions,
consolidations or combinations of the Common Shares occurring, in any such case,
prior to the Distribution Date.

                  Preferred Shares purchasable upon exercise of the Rights will
not be redeemable. Each Preferred Share will be entitled to a minimum
preferential quarterly dividend payment of $1.00 per share but will be entitled
to an aggregate dividend of 100 times the dividend declared per Common Share. In
the event of liquidation, the holders of the Preferred Shares will be entitled
to a minimum preferential liquidation payment of $100 per share but will be
entitled to an aggregate payment of 100 times the payment made per Common Share.
Each Preferred Share will have 100 votes, voting together with the Common
Shares. Finally, in the event of any merger, consolidation or other transaction
in which Common Shares are exchanged, each Preferred Share will be entitled to
receive 100 times the amount received per Common Share. These rights are
protected by customary antidilution provisions.

                  Because of the nature of the Preferred Shares' dividend,
liquidation and voting rights, the value of the one one-hundredth interest in a
Preferred Share purchasable upon exercise of each Right should approximate the
value of one Common Share.

                  In the event that the Company is acquired in a merger or other
business combination transaction or 50% or more of its consolidated assets or
earning power are sold, proper provision will be made so that each holder of a
Right will thereafter have the right to receive, upon the exercise thereof at
the then current exercise price of the Right, that number of shares of common
stock of the acquiring company which at the time of such transaction will have a
market value of two times the exercise price of the Right. In the event that any
person becomes an Acquiring Person, proper provision shall be made so that each
holder of a Right, other than Rights beneficially owned by the Acquiring Person
(which will thereafter be null and void), will thereafter have the right to
receive upon exercise that number of Common Shares having a market value of two
times the exercise price of the Right.

                  At any time after the acquisition by a person or group of
affiliated or associated persons of beneficial ownership of 20% or more of the
outstanding Common Shares, the Board of Directors of the Company may exchange
the Rights (other than Rights owned by such person or group which have become
null and void), in whole or in part, at an exchange ratio of one Common Share,
or one one-hundredth of a Preferred Share (or of a share of a class or series of
the Company's preferred stock having equivalent rights, preferences and
privileges), per Right (subject to adjustment).


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                  With certain exceptions, no adjustment in the Purchase Price
will be required until cumulative adjustments require an adjustment of at least
1% in such Purchase Price. No fractional Preferred Shares will be issued (other
than fractions which are integral multiples of one one-hundredth of a Preferred
Share, which may, at the election of the Company, be evidenced by depositary
receipts) and in lieu thereof, an adjustment in cash will be made based on the
market price of the Preferred Shares on the last trading day prior to the date
of exercise.

                  At any time prior to the close of business on the twentieth
day after the acquisition by a person or group of affiliated or associated
persons of beneficial ownership of 20% or more of the outstanding Common Shares,
the Board of Directors of the Company may redeem the Rights in whole, but not in
part, at a price of $.01 per Right (the "Redemption Price"). The redemption of
the rights may be made effective at such time on such basis and with such
conditions as the Board of Directors in its sole discretion may establish.
Immediately upon any redemption of the Rights, the right to exercise the Rights
will terminate and the only right of the holders of Rights will be to receive
the Redemption Price.

                  The terms of the Rights may be amended by the Board of
Directors of the Company without the consent of the holders of the Rights,
including an amendment to lower the threshold for exercisability of the Rights
from 20% to not less than the greater of (i) any percentage greater than the
largest percentage of the outstanding Common Shares then known to the Company to
be beneficially owned by any person or group of affiliated or associated persons
and (ii) 10%, except that from and after such time as any person becomes an
Acquiring Person no such amendment may adversely affect the interests of the
holders of the Rights.

                  Until a Right is exercised, the holder thereof, as such, will
have no rights as a stockholder of the Company, including, without limitation,
the right to vote or to receive dividends.

                  A copy of the Rights Agreement is available free of charge
from the Company. This summary description of the Rights does not purport to be
complete and is qualified in its entirety by reference to the Rights Agreement,
which is hereby incorporated herein by reference.

                  The Rights have certain anti-takeover effects. The Rights will
cause substantial dilution to a person or group that attempts to acquire the
Company on terms not approved by the Company's Board of Directors, except
pursuant to an offer conditioned on a substantial number of Rights being
acquired. The Rights should not interfere with any merger or other business
combination approved by the Board of Directors since the Rights may be redeemed
by the Company at $.01 per Right prior to the twentieth day after the time that
a person or group has acquired beneficial ownership of 20% or more of the Common
Shares.

                  The Rights Agreement, dated as of December 29, 1999, between
the Company and ChaseMellon Shareholder Services, L.L.C., as Rights Agent,
specifying the terms of the Rights and the Certificate of Designation setting
forth the terms of the Preferred Shares are attached hereto as exhibits and are
incorporated herein by reference. The foregoing description of the Rights is
qualified by reference to such exhibits.


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ITEM 7.  FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS

(c) Exhibit Index


        3(f)                 Amendment to Certificate of Designation of Series A
                             Preferred Stock of the Company filed with the
                             Secretary of State of the State of Delaware on
                             December 30, 1999.

        10(ss)               Rights Agreement dated as of December 29, 1999
                             between the Company and ChaseMellon Shareholder
                             Services, L.L.C., as Rights Agent, which includes
                             the form of Certificate of Designation setting
                             forth the terms of the Series A Preferred Stock,
                             $1.00 par value, as Exhibit A, the form of Right
                             Certificate as Exhibit B and the Summary of Rights
                             to Purchase Preferred Shares as Exhibit C. Pursuant
                             to the Rights Agreement, printed Right Certificates
                             will not be mailed until as soon as practicable
                             after the earlier of the tenth day after public
                             announcement that a person or group has acquired
                             beneficial ownership of 20% or more of the Common
                             Shares or the tenth day after a person commences or
                             announces its intention to commence a tender or
                             exchange offer the consummation of which would
                             result in the beneficial ownership by a person or
                             group of 20% or more of the Common Shares.


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                                    SIGNATURE


         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.



                                     NOVAMETRIX MEDICAL SYSTEMS INC.



Date: January 13, 2000               By: /s/ William J. Lacourciere
                                         ---------------------------------------
                                         William J. Lacourciere
                                         Chairman of the Board, President and
                                         Chief Executive Officer


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