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                                                                     EXHIBIT 4.1



                              AMENDED AND RESTATED
                            ARTICLES OF INCORPORATION
                                       OF
                        CYPROS PHARMACEUTICAL CORPORATION

        Paul J. Marangos and David W. Nassif hereby certify that:

        ONE: They are the duly elected and acting President and Secretary,
respectively, of Cypros Pharmaceutical Corporation, a California corporation
(the "Corporation").

        TWO: The Articles of Incorporation of this corporation are hereby
amended and restated to read as follows:


                                       I.

        The name of the Corporation is QUESTCOR PHARMACEUTICALS, INC. (the
"Corporation").


                                      II.

        The purpose of the Corporation is to engage in any lawful act or
activity for which a corporation may be organized under the General Corporation
Law of California other than the banking business, the trust company business or
the practice of a profession permitted to be incorporated by the California
Corporations Code.


                                      III.

        A. This Corporation is authorized to issue two classes of stock to be
designated, respectively, "Common Stock" and "Preferred Stock." The total number
of shares which the Corporation is authorized to issue is eighty-two million
five hundred thousand (82,500,000) shares, seventy-five million (75,000,000)
shares of which shall be Common Stock (the "Common Stock") and seven million
five hundred thousand (7,500,000) shares of which shall be Preferred Stock (the
"Preferred Stock").

        B. The Preferred Stock may be issued from time to time in one or more
series. The Board of Directors is hereby authorized, within the limitations and
restrictions stated in these Restated Articles of Incorporation, to fix or alter
the rights, preferences, privileges and restrictions granted to or imposed upon
any wholly unissued series of Preferred Stock, and the number of shares
constituting any such series and the designation thereof, or any of them; and to
increase or decrease the number of shares of any series prior or subsequent to
the issue of shares of that series, but not below the number of shares of such
series then outstanding. In case the number of shares of any series shall be so
decreased, the shares constituting such decrease shall resume the status which
they had prior to the adoption of the resolution originally fixing the number of
shares of such series.



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        C. Two million one hundred fifty-five thousand seven hundred fifteen
(2,155,715) of the authorized shares of Preferred Stock are hereby designated
"Series A Preferred Stock" (the "Series A Preferred").

        D. The rights, preferences, privileges, restrictions and other matters
relating to Common Stock and the Series A Preferred are as follows:

           1. DIVIDENDS. Holders of Series A Preferred shall be entitled to
receive dividends concurrently with dividends on the Common Stock, if any, on an
as-converted basis, when and as declared by the Board of Directors out of funds
legally available therefor. Such dividends shall be payable only when, as and if
declared by the Board of Directors and shall be non-cumulative.

           2. VOTING RIGHTS. The holder of each share of Series A Preferred
shall be entitled to the number of votes equal to the number of shares of Common
Stock into which each share of Series A Preferred could be converted on the
record date for the vote or written consent of shareholders and, except as
otherwise required by law or provided herein, shall have voting rights and
powers equal to the voting rights and powers of Common Stock. The holder of each
share of Series A Preferred shall be entitled to notice of any shareholders'
meeting in accordance with the bylaws of the Corporation and shall vote with
holders of Common Stock upon the election of directors and upon any other matter
submitted to a vote of shareholders, except those matters required by law to be
submitted to a class vote. Fractional votes shall not, however, be permitted and
any fractional voting rights resulting from the above formula (after aggregating
all shares of Common Stock into which shares of Series A Preferred held by each
holder could be converted) shall be rounded to the nearest whole number (with
one-half rounded upward to one). Each holder of Common Stock shall be entitled
to one (1) vote for each share of Common Stock held.

           3. LIQUIDATION RIGHTS.

              (a) Upon any liquidation, dissolution, or winding up of the
Corporation, whether voluntary or involuntary, before any distribution or
payment shall be made to the holders of the Common Stock, the holders of Series
A Preferred shall be entitled to be paid out of the assets of the Corporation an
amount per share of Series A Preferred equal to the "Original Issue Price" plus
all declared and unpaid dividends on the Series A Preferred (as adjusted for any
stock dividends, combinations, splits, recapitalizations and the like with
respect to such shares) for each share of Series A Preferred held by them. The
Original Issue Price of the Series A Preferred shall be $4.639 per share. If,
upon any liquidation, distribution, or winding up, the assets of the Corporation
available for distribution to the Series A Preferred shall be insufficient to
make payment in full to all holders of Series A Preferred of the liquidation
preference set forth in this Section 3(a), then such assets shall be distributed
among the holders of Series A Preferred at the time outstanding, ratably in
proportion to the full amounts to which they would otherwise be respectively
entitled. After payment of the full liquidation preference of the Series A
Preferred as set forth in this Section 3(a), the entire assets of the



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Corporation legally available for distribution, if any, shall be distributed
ratably to the holders of the Common Stock.

              (b) The following events shall be considered a liquidation under
this Section:

                  (i) any consolidation or merger of the Corporation with or
into any other corporation or other entity or person, or any other corporate
reorganization, in each case in which the shareholders of the Corporation
immediately prior to such consolidation, merger or reorganization, own less than
50% of the Corporation's voting power immediately after such consolidation,
merger or reorganization, or any transaction or series of related transactions
in which in excess of 50% of the Corporation's voting power is transferred (an
"Acquisition"); or

                  (ii) a sale, lease or other disposition of all or
substantially all of the assets of the Corporation (an "Asset Transfer").

        4. CONVERSION RIGHTS. The holders of the Series A Preferred shall have
the following rights with respect to the conversion of the Series A Preferred
into shares of Common Stock (the "Conversion Shares"):

           (a) OPTIONAL CONVERSION.

               (i) Subject to and in compliance with the provisions of this
Section 4(a), each holder of Series A Preferred shall have the right, at its
option, to convert up to a number of shares of Series A Preferred equal to the
number of shares of such Series A Preferred then held by such holder multiplied
by a fraction, the numerator of which shall be one (1), and the denominator of
which shall be three (3) at any time prior to the "Measurement Date", and
reduced by one (1) each on the Measurement Date and on the first anniversary
following the Measurement Date, such that one-third (1/3) of the shares held by
a holder may be converted immediately, and all shares held by a holder may be
converted on the date that is one year after the Measurement Date. "Measurement
Date" shall mean December 1, 1999.

               (ii) The number of shares of Common Stock to which a holder of
Series A Preferred shall be entitled upon conversion shall be the product
obtained by multiplying the "Series A Conversion Rate" then in effect
(determined as provided in Section 4(b)) by the number of shares of Series A
Preferred being converted.

           (b) SERIES A CONVERSION RATE. The conversion rate in effect at any
time for conversion of the Series A Preferred (the "Series A Conversion Rate")
shall be the quotient obtained by dividing the Original Issue Price of the
Series A Preferred by the "Series A Preferred Price" as defined in Section 4(c).

           (c) SERIES A PREFERRED PRICE. The conversion price for the Series A
Preferred shall initially be the Original Issue Price of the Series A Preferred
(the "Series A Preferred Price"). Such initial Series A Preferred Price shall be
adjusted from



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time to time in accordance with this Section 4. All references to the Series A
Preferred Price herein shall mean the Series A Preferred Price as so adjusted.

           (d) CLOSING PRICE. "Closing Price" with respect to a share of Common
Stock shall mean the closing sale price or the average of the reported closing
bid and asked prices, as the case may be, on the principal national security
exchange or quotation system on which the Common Stock is quoted or listed or
admitted to trading, or, if not quoted or listed or admitted to trading on any
national securities or quotation system, the average of the closing bid and
asked prices of the Common Stock on the over-the-counter market as reported by
the National Quotation Bureau Incorporated, or a similar generally accepted
reporting service, or if not so available, in such manner as furnished by any
New York Stock Exchange member firm selected from time to time by the Board of
Directors for that purpose, or a price determined in good faith by the Board of
Directors, whose determination shall be conclusive and described in a Board
Resolution, and

           (e) CURRENT MARKET VALUE. "Current Market Value" of a share of Common
Stock shall mean the average of the daily Closing Prices per share of Common
Stock for the ten (10) consecutive trading days immediately prior to the date in
question.

           (f) MECHANICS OF CONVERSION. Each holder of Series A Preferred who
desires to convert the same into shares of Common Stock pursuant to this Section
4 shall surrender the certificate or certificates therefor, duly endorsed, at
the office of the Corporation or any transfer agent for the Series A Preferred,
and shall give written notice to the Corporation at such office that such holder
elects to convert the same. Such notice shall state the number of shares of
Series A Preferred being converted. Thereupon, the Corporation shall promptly
issue and deliver at such office to such holder a certificate or certificates
for the number of shares of Common Stock to which such holder is entitled and
shall promptly pay in cash or, to the extent sufficient funds are not then
legally available therefor, in Common Stock (at the Common Stock's Current
Market Value as of the date of such conversion), any declared and unpaid
dividends on the shares of Series A Preferred being converted as well as
promptly pay in cash any payment in lieu of issuing a fractional share as set
forth in Section 4(n). Such conversion shall be deemed to have been made at the
close of business on the date of such surrender of the certificates representing
the shares of Series A Preferred to be converted, and the person entitled to
receive the shares of Common Stock issuable upon such conversion shall be
treated for all purposes as the record holder of such shares of Common Stock on
such date.

           (g) ADJUSTMENT FOR STOCK SPLITS AND COMBINATIONS. If the Corporation
shall at any time or from time to time after the date that the first share of
Series A Preferred is issued by the Corporation (the "Original Issue Date")
effect a subdivision of the outstanding Common Stock without a corresponding
subdivision of the Preferred Stock, the Series A Preferred Price in effect
immediately before that subdivision shall be proportionately decreased.
Conversely, if the Corporation shall at any time or from time to time after the
Original Issue Date combine the outstanding shares of Common Stock into a
smaller number of shares without a corresponding combination of



                                       4.
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the Preferred Stock, the Series A Preferred Price in effect immediately before
the combination shall be proportionately increased. Any adjustment under this
Section 4(g) shall become effective at the close of business on the date the
subdivision or combination becomes effective.

           (h) ADJUSTMENTS FOR OTHER DIVIDENDS AND DISTRIBUTIONS. If the
Corporation at any time or from time to time after the Original Issue Date
makes, or fixes a record date for the determination of holders of Common Stock
entitled to receive, a dividend or other distribution payable in securities of
the Corporation other than shares of Common Stock, in each such event provision
shall be made so that the holders of the Series A Preferred shall receive upon
conversion thereof, in addition to the number of shares of Common Stock
receivable thereupon, the amount of other securities of the Corporation which
they would have received had their Series A Preferred been converted into Common
Stock on the date of such event and had they thereafter, during the period from
the date of such event to and including the conversion date, retained such
securities receivable by them as aforesaid during such period, subject to all
other adjustments called for during such period under this Section 4 with
respect to the rights of the holders of the Series A Preferred or with respect
to such other securities by their terms.

           (i) ADJUSTMENT FOR RECLASSIFICATION, EXCHANGE AND SUBSTITUTION. If at
any time or from time to time after the Original Issue Date, the Common Stock
issuable upon the conversion of the Series A Preferred is changed into the same
or a different number of shares of any class or classes of stock, whether by
recapitalization, reclassification or otherwise (other than a subdivision or
combination of shares or stock dividend or a reorganization, merger,
consolidation or sale of assets provided for elsewhere in this Section 4), in
any such event each holder of Series A Preferred shall have the right thereafter
to convert such stock into the kind and amount of stock and other securities and
property receivable upon such recapitalization, reclassification or other change
by holders of the maximum number of shares of Common Stock into which such
shares of Series A Preferred could have been converted immediately prior to such
recapitalization, reclassification or change, all subject to further adjustment
as provided herein or with respect to such other securities or property by the
terms thereof.

           (j) REORGANIZATIONS, MERGERS, CONSOLIDATIONS OR SALES OF ASSETS. If
at any time or from time to time after the Original Issue Date, there is a
capital reorganization of the Common Stock (other than an Acquisition or Asset
Transfer as defined in Section 3(b) or a recapitalization, subdivision,
combination, reclassification, exchange or substitution of shares provided for
elsewhere in this Section 4), as a part of such capital reorganization,
provision shall be made so that the holders of the Series A Preferred shall
thereafter be entitled to receive upon conversion of the Series A Preferred the
number of shares of stock or other securities or property of the Corporation to
which a holder of the maximum number of shares of Common Stock deliverable upon
conversion would have been entitled on such capital reorganization, subject to
adjustment in respect of such stock or securities by the terms thereof. In any
such case, appropriate adjustment shall be made in the application of the
provisions of this Section 4 with respect to the rights of the holders of Series
A Preferred after the capital reorganization to the end that



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the provisions of this Section 4 (including adjustment of the Series A Preferred
Price then in effect and the number of shares issuable upon conversion of the
Series A Preferred) shall be applicable after that event and be as nearly
equivalent as practicable.

           (k) CERTIFICATE OF ADJUSTMENT. In each case of an adjustment or
readjustment of the Series A Preferred Price for the number of shares of Common
Stock or other securities issuable upon conversion of the Series A Preferred, if
the Series A Preferred is then convertible pursuant to this Section 4, the
Corporation, at its expense, shall compute such adjustment or readjustment in
accordance with the provisions hereof and prepare a certificate showing such
adjustment or readjustment, and shall mail such certificate, by first class
mail, postage prepaid, to each registered holder of Series A Preferred at the
holder's address as shown in the Corporation's books. The certificate shall set
forth such adjustment or readjustment, showing in detail the facts upon which
such adjustment or readjustment is based.

           (l) NOTICES OF RECORD DATE. Upon (i) any taking by the Corporation of
a record of the holders of any class of securities for the purpose of
determining the holders thereof who are entitled to receive any dividend or
other distribution, or (ii) any acquisition or other capital reorganization of
the Corporation, any reclassification or recapitalization of the capital stock
of the Corporation, any merger or consolidation of the Corporation with or into
any other corporation, or any voluntary or involuntary dissolution, liquidation
or winding up of the Corporation, the Corporation shall mail to each holder of
Series A Preferred at least twenty (20) days prior to the record date specified
therein a notice specifying (1) the date on which any such record is to be taken
for the purpose of such dividend or distribution and a description of such
dividend or distribution, (2) the date on which any such acquisition,
reorganization, reclassification, transfer, consolidation, merger, dissolution,
liquidation or winding up is expected to become effective, and (3) the date, if
any, that is to be fixed as to when the holders of record of Common Stock (or
other securities) shall be entitled to exchange their shares of Common Stock (or
other securities) for securities or other property deliverable upon such
acquisition, reorganization, reclassification, transfer, consolidation, merger,
dissolution, liquidation or winding up.

           (m) CONVERSION BY THE CORPORATION.

               (i) Subject to Section 403(a)(3) and Section 301.5(d) of the
California Corporations Code, so long as the average of the daily Closing Prices
per share of Common Stock for the fifteen (15) consecutive trading days
immediately prior to the date in question is at least $12.00 per share (as
adjusted for any stock dividends, combinations, splits, recapitalizations and
the like), each share of Series A Preferred, at the option of the Corporation
upon notice to the holders of Series A Preferred, shall be converted into shares
of Common Stock; provided, however, that no such conversion shall occur unless
the Corporation is a "listed corporation" (as defined in Section 301.5(d) of the
California Corporations Code) both at the time of the original issuance of the
shares of Series A Preferred and at the time of conversion of the shares of
Series A Preferred, and the shares of Common Stock received upon conversion of
the Series A Preferred are listed or qualified for trading on a stock exchange
or market system defined in Section 301.5(d)



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of the California Corporations Code, and provided further, that no such
conversion shall occur if, as a result of such conversion, the Conversion Shares
in the aggregate would constitute 20% or more of the then issued and outstanding
shares of Common Stock. Upon such conversion, any declared and unpaid dividends
shall be paid in accordance with the provisions of Section 4(f);

               (ii) Upon written notice to the holders of Series A Preferred by
the Corporation, the outstanding shares of Series A Preferred shall be converted
without any further action by the holders of such shares and whether or not the
certificates representing such shares are surrendered to the Corporation or its
transfer agent; provided, however, that the Corporation shall not be obligated
to issue certificates evidencing the shares of Common Stock issuable upon such
conversion unless the certificates evidencing such shares of Series A Preferred
are either delivered to the Corporation or its transfer agent as provided below,
or the holder notifies the Corporation or its transfer agent that such
certificates have been lost, stolen or destroyed and executes an agreement
satisfactory to the Corporation to indemnify the Corporation from any loss
incurred by it in connection with such certificates. Upon the occurrence of such
conversion of the Series A Preferred, the holders of Series A Preferred shall
surrender the certificates representing such shares at the office of the
Corporation or any transfer agent for the Series A Preferred. Thereupon, there
shall be issued and delivered to such holder promptly at such office and in its
name as shown on such surrendered certificate or certificates, a certificate or
certificates for the number of shares of Common Stock into which the shares of
Series A Preferred surrendered were convertible on the date on which such
conversion occurred, and any declared and unpaid dividends shall be paid in
accordance with the provisions of Section 4(f).

           (n) FRACTIONAL SHARES. No fractional shares of Common Stock shall be
issued upon conversion of Series A Preferred. All shares of Common Stock
(including fractions thereof) issuable upon conversion of more than one share of
Series A Preferred by a holder thereof shall be aggregated for purposes of
determining whether the conversion would result in the issuance of any
fractional share. If, after the aforementioned aggregation, the conversion would
result in the issuance of any fractional share, the Corporation shall, in lieu
of issuing any fractional share, pay cash equal to the product of such fraction
multiplied by the Common Stock's Current Market Value on the date of conversion.

           (o) RESERVATION OF STOCK ISSUABLE UPON CONVERSION. The Corporation
shall at all times reserve and keep available out of its authorized but unissued
shares of Common Stock, solely for the purpose of effecting the conversion of
the shares of the Series A Preferred, such number of its shares of Common Stock
as shall from time to time be sufficient to effect the conversion of all
outstanding shares of the Series A Preferred. If at any time the number of
authorized but unissued shares of Common Stock shall not be sufficient to effect
the conversion of all then outstanding shares of the Series A Preferred, the
Corporation will take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of Common
Stock to such number of shares as shall be sufficient for such purpose.



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              (p) NOTICES. Any notice required by the provisions of this Section
4 shall be in writing and shall be deemed effectively given: (i) upon personal
delivery to the party to be notified, (ii) when sent by facsimile if sent during
normal business hours of the recipient; if not, then on the next business day,
(iii) five (5) days after having been sent by registered or certified mail,
return receipt requested, postage prepaid, or (iv) one (1) day after deposit
with a nationally recognized overnight courier, specifying next day delivery,
with written verification of receipt. All notices shall be addressed to each
holder of record at the address of such holder appearing on the books of the
Corporation.

              (q) PAYMENT OF TAXES. The Corporation will pay all taxes (other
than taxes based upon income) and other governmental charges that may be imposed
with respect to the issue or delivery of shares of Common Stock upon conversion
of shares of Series A Preferred, excluding any tax or other charge imposed in
connection with any transfer involved in the issue and delivery of shares of
Common Stock in a name other than that in which the shares of Series A Preferred
so converted were registered.

           5. NO REISSUANCE OF SERIES A PREFERRED. No share or shares of Series
A Preferred acquired by the Corporation by reason of redemption, purchase,
conversion or otherwise shall be reissued; and in addition, the Articles of
Incorporation shall be appropriately amended to effect the corresponding
reduction in the Corporation's authorized stock.

           6. RESIDUAL RIGHTS. All rights accruing to the outstanding shares of
the Corporation not expressly provided for to the contrary herein shall be
vested in the Common Stock.


                                      IV.

        A. The liability of the directors of the Corporation for monetary
damages shall be eliminated to the fullest extent permissible under California
law.

        B. The Corporation is authorized to provide indemnification of agents
(as defined in Section 317 of the General Corporation Law of California) for
breach of duty to the Corporation and its shareholders through bylaw provisions
or through agreements with agents, or both, in excess of the indemnification
otherwise permitted by Section 317 of the General Corporation Law of California,
subject to the limits on such excess indemnification set forth in Section 204 of
the General Corporation Law of California. If, after the effective date of this
Article, California law is amended in a manner which permits a corporation to
limit the monetary or other liability of its directors or to authorize
indemnification of, or advancement of such defense expenses to, its directors or
other persons, in any such case to a greater extent than is permitted on such
effective date, the references in this Article to "California law" shall to that
extent be deemed to refer to California law as so amended.



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        C. Any repeal or modification of this Article shall only be prospective
and shall not effect the rights under this Article in effect at the time of the
alleged occurrence of any action or omission to act giving rise to liability."

        THREE: The foregoing amendment and restatement of the Articles of
Incorporation has been duly approved by the Board of Directors of this
Corporation.

        FOUR: The foregoing amendment and restatement of the Articles of
Incorporation has been duly approved by the required vote of shareholders in
accordance with Section 902 of the California Corporations Code. The Corporation
has one class of stock outstanding and such class of stock is entitled to vote
with respect to the amendment herein set forth. The total number of outstanding
shares of Common Stock of the Corporation entitled to vote on the amendment is
15,735,007 shares of Common Stock. No shares of Preferred Stock are outstanding.
The number of shares voting in favor of the amendment equaled or exceeded the
vote required. The percentage vote required was more than fifty percent (50%) of
the outstanding Common Stock voting as a class.



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        The undersigned, Paul J. Marangos and David W. Nassif, the President and
Secretary, respectively, of CYPROS PHARMACEUTICAL CORPORATION, declare under
penalty of perjury under the laws of the State of California that the matters
set out in the foregoing Certificate are true of their own knowledge.

        Executed at Carlsbad, California on November 5, 1999.





                                            /s/ Paul J. Marangos
                                            -----------------------------------
                                            Paul J. Marangos, President



                                            /s/ David W. Nassif
                                            -----------------------------------
                                            David W. Nassif, Secretary



                                      10.