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                                                                    EXHIBIT 10.1

                              CONNETICS CORPORATION
                        1995 EMPLOYEE STOCK PURCHASE PLAN
                  (AS AMENDED AND RESTATED THROUGH MAY 7, 2004)
                 Adopted by the Board of Directors Feb. 17, 2000
                    Approved by the Stockholders May 11, 2000

1.    PURPOSE. The purpose of the Plan is to provide employees of the Company
and its Designated Subsidiaries with an opportunity to purchase Common Stock of
the Company. It is the intention of the Company to have the Plan qualify as an
"Employee Stock Purchase Plan" under Section 423 of the Internal Revenue Code of
1986, as amended. The provisions of the Plan shall, accordingly, be construed so
as to extend and limit participation in a manner consistent with the
requirements of that section of the Code.

2.    DEFINITIONS.

      (a)   "Board" means the Board of Directors of the Company.

      (b)   "Code" means the Internal Revenue Code of 1986, as amended.

      (c)   "Common Stock" means the Common Stock of the Company.

      (d)   "Company" means Connetics Corporation a Delaware corporation.

      (e)   "Compensation" means all regular straight time gross earnings,
excluding payments for overtime, shift premium, incentive compensation,
incentive payments, bonuses, commissions and other compensation.

      (f)   "Continuous Status as an Employee" means the absence of any
interruption or termination of service as an Employee. Continuous Status as an
Employee shall not be considered interrupted in the case of a leave of absence
agreed to in writing by the Company, provided that such leave is for a period of
not more than 90 days or reemployment upon the expiration of such leave is
guaranteed by contract or statute.

      (g)   "Contributions" means all amounts credited to the account of a
participant pursuant to the Plan.

      (h)   "Designated Subsidiaries" means the Subsidiaries which have been
designated by the Board from time to time in its sole discretion as eligible to
participate in the Plan.

      (i)   "Employee" means any person, including an Officer, who is
customarily employed for at least twenty (20) hours per week and more than five
(5) months in a calendar year by the Company or one of its Designated
Subsidiaries.

      (j)   "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

      (k)   "Purchase Date" means the last day of each Purchase Period of the
Plan.

      (l)   "Offering" means the grant of rights to purchase Common Stock of the
Company under the Plan to eligible Employees.

      (m)   "Offering Date" means the first business day of each Offering Period
of the Plan. In the case of an individual who becomes an eligible Employee after
the first business day of an Offering Period but prior to the first business day
of the last calendar quarter of such Offering Period, the term "Offering Date"
means the first business day of the calendar quarter coinciding with or next
succeeding the day on which that individual becomes an eligible Employee.
Options granted after the first business day of an Offering Period will be
subject to the same terms as the options granted on the first business day of
such Offering Period except that they will have a different grant date (thus,
potentially, a different exercise price) and, because they expire at the same
time as the options granted on the first business day of such Offering Period, a
shorter term.

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      (n)   "Offering Period" means a period of twenty-four (24) months
commencing on December 1 and June 1 of each year, except as otherwise set forth
in SECTION 4(a), or such other period as the Board of Directors may determine
prior to the commencement of an Offering Period, but which period shall not
exceed twenty-four (24) months.

      (o)   "Officer" means a person who is an officer of the Company within the
meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated under the Exchange Act.

      (p)   "Option Price" means the price at which the shares are offered in a
given Offering Period, calculated as set forth in SECTION 7(b).

      (q)   "Plan" means this Employee Stock Purchase Plan.

      (r)   "Purchase Period" means a period of six (6) months within an
            Offering Period.

      (s)   "Subsidiary" means a corporation, domestic or foreign, of which not
less than 50% of the voting shares are held by the Company or a Subsidiary,
whether or not such corporation now exists or is hereafter organized or acquired
by the Company or a Subsidiary.

3.    ELIGIBILITY.

      (a)   Any person who is an Employee as of the Offering Date of a given
Offering Period shall be eligible to participate in such Offering Period under
the Plan subject to the requirements of SECTION 5(a) and the limitations imposed
by Section 423(b) of the Code.

      (b)   Any provisions of the Plan to the contrary notwithstanding, no
Employee shall be granted an option under the Plan (i) if, immediately after the
grant, such Employee (or any other person whose stock would be attributed to
such Employee pursuant to Section 424(d) of the Code) would own stock and/or
hold outstanding options to purchase stock possessing five percent (5%) or more
of the total combined voting power or value of all classes of stock of the
Company or of any subsidiary of the Company, or (ii) if such option would permit
his or her rights to purchase stock under all employee stock purchase plans
(described in Section 423 of the Code) of the Company and its Subsidiaries to
accrue at a rate which exceeds Twenty-Five Thousand Dollars ($25,000) of fair
market value of such stock (determined at the time such option is granted) for
each calendar year in which such option is outstanding at any time.

4.    OFFERING PERIODS AND PURCHASE PERIODS.

      (a)   Offering Periods. The Plan shall be implemented by a series of
Offering Periods of twenty-four (24) months duration, with new Offering Periods
commencing on or about June 1 and December 1 of each year (or at such other time
or times as may be determined by the Board of Directors). In particular, upon
adoption of this Plan as amended and restated, a new Offering Period shall
commence on June 1, 2003. The Plan shall continue until terminated in accordance
with SECTION 20 of this Plan. The Board of Directors of the Company shall have
the power to change the duration and/or the frequency of Offering Periods with
respect to future offerings without stockholder approval if such change is
announced at least fifteen (15) days prior to the scheduled beginning of the
first Offering Period to be affected. The terms and conditions of an Offering
Period shall be incorporated by reference into the Plan and treated as part of
the Plan. The provisions of separate Offering Periods need not be identical, but
each Offering shall include (thorough incorporation of the provisions of this
Plan by reference into the document comprising the Offering or otherwise) the
Offering Period, and the substance of the provisions contained in SECTIONS 5
through 13, inclusive. An Employee may only participate in one Offering Period
at a time.

      (b)   Purchase Periods. Each Offering Period shall consist of consecutive
Purchase Periods of six (6) months duration. The last day of each Purchase
Period shall be the "Purchase Date" for such Purchase Period. A Purchase Period
commencing on June 1 shall end on the next November 30. A Purchase Period
commencing on December 1 shall end on the next May 31. In particular, upon
adoption of this Plan as amended and restated, a new Purchase Period shall
commence on June 1, 2003. The Board of Directors of the Company shall have the
power to change the duration and/or frequency of Purchase Periods with respect
to future purchases without stockholder

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approval if such change is announced at least fifteen (15) days prior to the
scheduled beginning of the first Purchase Period to be affected.

5.    PARTICIPATION.

      (a)   An eligible Employee may become a participant in the Plan by
completing a subscription agreement on the form provided by the Company and
filing it with the Company's payroll office prior to the applicable Offering
Date, unless a later time for filing the subscription agreement is set by the
Board for all eligible Employees with respect to a given offering. The
subscription agreement shall set forth the percentage of the participant's
Compensation (which shall be greater than or equal to zero percent (0%) but not
more than fifteen percent (15%)) to be paid as Contributions pursuant to the
Plan.

      (b)   Payroll deductions shall commence on the first payroll following the
Offering Date and shall end on the last payroll paid on or prior to the last
Purchase Period of the Offering Period to which the subscription agreement is
applicable, unless sooner terminated by the participant as provided in SECTION
10.

6.    METHOD OF PAYMENT OF CONTRIBUTIONS.

      (a)   The participant shall elect to have payroll deductions made on each
payday during the Offering Period in an amount greater than or equal to zero
percent (0%) but not more than fifteen percent (15%) of such participant's
Compensation on each such payday. All payroll deductions made by a participant
shall be credited to his or her account under the Plan. A participant may not
make any additional payments into such account.

      (b)   A participant may discontinue his or her participation in the Plan
as provided in SECTION 10, or, on one occasion only during a Purchase Period,
may increase or decrease the rate of his or her Contributions during the
Offering Period by completing and filing with the Company a change of status
notice. The change in rate shall be effective for the first full payroll period
commencing no fewer than ten (10) business days following the Company's receipt
of the change of status notice, unless this change is processed more quickly.

      (c)   Notwithstanding the foregoing, to the extent necessary to comply
with Section 423(b)(8) of the Code and SECTION 3(b) of this Plan, a
participant's payroll deductions may be decreased to 0% at such time during any
Offering Period which is scheduled to end during the current calendar year that
the aggregate of all payroll deductions accumulated with respect to such
Offering Period and any other Offering Period ending within the same calendar
year equal $25,000. Payroll deductions shall re-commence at the rate provided in
such participant's subscription Agreement at the beginning of the first Offering
Period which is scheduled to end in the following calendar year, unless
terminated by the participant as provided in SECTION 10.

7.    GRANT OF OPTION.

      (a)   On the Offering Date of each Offering Period, each eligible Employee
participating in such Offering Period shall be granted an option to purchase on
each Purchase Date a number of shares of the Company's Common Stock determined
by dividing such Employee's Contributions accumulated prior to such Purchase
Date and retained in the participant's account as of the Purchase Date by the
Option Price; provided however, that the maximum number of shares an Employee
may purchase during each Offering Period shall be determined at the Offering
Date by dividing $50,000 by the fair market value of a share of the Company's
Common Stock on the Offering Date, and provided further that such purchase shall
be subject to the limitations set forth in SECTIONS 3(b) and 13. The fair market
value of a share of the Company's Common Stock shall be determined as provided
in SECTION 7(b).

      (b)   The option price per share of the shares offered in a given Offering
Period ("Option Price") shall be the lower of:

      (i)   eighty-five percent (85%) of the fair market value of a share of the
            Company's Common Stock on the Offering Date, or

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      (ii)  eighty-five percent (85%) of the fair market value of a share of the
            Company's Common Stock on the Purchase Date;

The fair market value of the Company's Common Stock on a given date shall be
determined by the Board in its discretion based on the closing price of the
Common Stock for such date (or, in the event that the Common Stock is not traded
on such date, on the immediately preceding trading date), as reported by the
National Association of Securities Dealers Automated Quotation (Nasdaq) National
Market or, if such price is not reported, the mean of the bid and asked prices
per share of the Common Stock as reported by Nasdaq or, in the event the Common
Stock is listed on a stock exchange, the fair market value per share shall be
the closing price on such exchange on such date (or, in the event that the
Common Stock is not traded on such date, on the immediately preceding trading
date), as reported in The Wall Street Journal.

      (c)   In connection with each Offering made under the Plan, the Board or
the Committee may specify a maximum number of shares that may be purchased by
any employee as well as a maximum aggregate number of shares that may be
purchased by all eligible employees pursuant to such Offering. In addition, in
connection with each Offering that contains more than one Purchase Date, the
Board or the Committee may specify a maximum aggregate number of shares which
may be purchased by all eligible employees on any give Purchase Date under the
Offering. If the aggregate purchase of shares upon exercise of rights granted
under the Offering would exceed any such maximum aggregate number, the Board or
the Committee shall make a pro rata allocation of the shares available in as
nearly a uniform manner as is practicable and as it deems to be equitable.

8.    EXERCISE OF OPTION. Unless a participant withdraws from the Plan as
provided in SECTION 10, his or her option for the purchase of shares will be
exercised automatically on each Purchase Date of an Offering Period, and the
maximum number of shares, including fractional shares, subject to the option
will be purchased at the applicable option price with the accumulated
Contributions in his or her account. The shares purchased upon exercise of an
option hereunder shall be deemed to be transferred to the participant on the
Purchase Date. During his or her lifetime, a participant's option to purchase
shares hereunder is exercisable only by him or her.

9.    DELIVERY. As promptly as practicable after each Purchase Date of each
Offering Period, the Company shall arrange the delivery to each participant, as
appropriate, of a certificate representing the shares purchased upon exercise of
his or her option or the deposit of such number of shares with the broker
selected by the Company for administration of Plan stock purchases, as
determined by the Company. Any cash remaining to the credit of a participant's
account under the Plan after a purchase by him or her of shares at the
termination of each Offering Period, or which is insufficient to purchase a full
share of Common Stock of the Company, shall be carried over to the next Offering
Period if the Employee continues to participate in the Plan, or if the Employee
does not continue to participate, shall be returned to said participant.

10.   VOLUNTARY WITHDRAWAL; TERMINATION OF EMPLOYMENT.

      (a)   A participant may withdraw all but not less than all the
Contributions credited to his or her account under the Plan at any time prior to
each Purchase Date by giving written notice to the Company. All of the
participant's Contributions credited to his or her account will be paid to him
or her promptly after receipt of his or her notice of withdrawal and his or her
option for the current period will be automatically terminated, and no further
Contributions for the purchase of shares will be made during the Offering
Period.

      (b)   Upon termination of the participant's Continuous Status as an
Employee prior to the Purchase Date of an Offering Period for any reason,
including retirement or death, the Contributions credited to his or her account
will be returned to him or her or, in the case of his or her death, to the
person or persons entitled thereto under SECTION 15, and his or her option will
be automatically terminated.

      (c)   If an Employee fails to remain in Continuous Status as an Employee
of the Company for at least twenty (20) hours per week during the Offering
Period in which the employee is a participant, he or she will be deemed to have
elected to withdraw from the Plan and the Contributions credited to his or her
account will be returned to him or her and his or her option terminated.

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      (d)   A participant's withdrawal from an offering will not have any effect
upon his or her eligibility to participate in a succeeding offering or in any
similar plan which the Company may adopt after the date of this Plan.

11.   AUTOMATIC WITHDRAWAL. If on the Purchase Date of any Purchase Period in an
Offering Period, the fair market value of the shares is lower than it was on the
Offering Date of such Offering Period (after taking into account any adjustment
during the Offering Period pursuant to SECTION 19(a)), all participants in such
Offering Period shall (a) acquire the shares reserved for the participant for
such Purchase Period, and (b) automatically be (i) withdrawn from the Offering
Period following the acquisition of shares, and (ii) enrolled in the Offering
Period that commences on the next business day.

12.   INTEREST.

      (a)   All payroll deductions credited to the account of a participant
under the Plan shall accrue interest. In the case of participants primarily
employed in Australia, such amounts credited to a participant's account shall be
deposited with a bank in Australia. In the case of participants primarily
employed in the United States, such amounts credited to a participant's account
shall be deposited with a bank in the United States. With respect to
participants employed in other jurisdictions, the Board shall determine the
location of the bank where amounts credited to a participant's account shall be
deposited.

      (b)   Any interest attributable to amounts credited to the account of a
participant under the Plan shall be paid to the account of the participant and
shall form part of that participant's Contributions.

      (c)   The Company shall be entitled to deduct from the interest earned on
amounts credited to the account of a participant any bank and government charges
referable to that participant's Contributions and an amount representing a
reasonable apportionment of the cost of administering the Plan, as determined by
the Board from time to time. In addition, the Company shall be entitled to
withhold from such interest an amount sufficient to satisfy any applicable
income and employment tax withholding obligations.

      (d)   The Company shall advise each participant of the amount of interest
(net of any bank, government and administration charges deducted) earned in
respect of amounts credited to the account of a participant for the relevant tax
period.

13.   STOCK SUBJECT TO THE PLAN.

      (a)   Subject to adjustment upon changes in capitalization of the Company
as provided in SECTION 19(a), the maximum aggregate number of Shares which may
be optioned and sold under the Plan shall be Eight Hundred Thousand (800,000)
shares, plus an annual increase to be added on each November 30, equal to the
lesser of:

      (i)   one half of one percent (0.5%) of the total number of shares of
            Common Stock outstanding on such anniversary date; or

      (ii)  a number of shares determined by the Board prior to the anniversary
            date, which number shall be less than (i) above.

The Shares may be authorized, but unissued, or reacquired Common Stock. If the
total number of shares which would otherwise be subject to options granted
pursuant to SECTION 7(a) on the Offering Date of an Offering Period exceeds the
number of shares then available under the Plan (after deduction of all shares
for which options have been exercised or are then outstanding), the Company
shall make a pro rata allocation of the shares remaining available for option
grant in as uniform a manner as shall be practicable and as it shall determine
to be equitable. In such event, the Company shall give written notice of such
reduction of the number of shares subject to the option to each Employee
affected thereby and shall similarly reduce the rate of Contributions, if
necessary.

      (b)   The participant will have no interest or voting right in shares
covered by his or her option until such option has been exercised.

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      (c)   Shares to be delivered to a participant under the Plan will be
registered in the name of the participant or in the name of the participant and
his or her spouse.

14.   ADMINISTRATION. The Board, or a committee named by the Board, shall
supervise and administer the Plan and shall have full power to adopt, amend and
rescind any rules deemed desirable and appropriate for the administration of the
Plan and not inconsistent with the Plan, to determine when and how rights to
purchase stock of the Company shall be granted and the provisions of each such
Offering Period (which need not be identical), to construe and interpret the
Plan and rights granted under it, and to establish, amend and revoke rules and
regulations for the administration of the Plan. The composition of the committee
shall be in accordance with the requirements to obtain or retain any available
exemption from the operation of Section 16(b) of the Exchange Act pursuant to
Rule 16b-3 under the Exchange Act.

15.   DESIGNATION OF BENEFICIARY.

      (a)   A participant may file a written designation of a beneficiary who is
to receive any shares and cash, if any, from the participant's account under the
Plan in the event of such participant's death subsequent to the end of a
Purchase Period but prior to delivery to him or her of such shares and cash. In
addition, a participant may file a written designation of a beneficiary who is
to receive any cash from the participant's account under the Plan in the event
of such participant's death prior to the Purchase Date of an Offering Period. If
a participant is married and the designated beneficiary is not the spouse,
spousal consent shall be required for such designation to be effective.

      (b)   Such designation of beneficiary may be changed by the participant
(and his or her spouse, if any) at any time by written notice. In the event of
the death of a participant and in the absence of a beneficiary validly
designated under the Plan who is living at the time of such participant's death,
the Company shall deliver such shares and/or cash to the executor or
administrator of the estate of the participant, or if no such executor or
administrator has been appointed (to the knowledge of the Company), the Company,
in its discretion, may deliver such shares and/or cash to the spouse or to any
one or more dependents or relatives of the participant, or if no spouse,
dependent or relative is known to the Company, then to such other person as the
Company may designate.

16.   TRANSFERABILITY. Neither Contributions credited to a participant's account
nor any rights with regard to the exercise of an option or to receive shares
under the Plan may be assigned, transferred, pledged or otherwise disposed of in
any way (other than by will, the laws of descent and distribution, or as
provided in SECTION 15) by the participant. Any such attempt at assignment,
transfer, pledge or other disposition shall be without effect, except that the
Company may treat such act as an election to withdraw funds in accordance with
SECTION 10.

17.   USE OF FUNDS. Contributions received by the Company under the Plan shall
constitute general funds of the Company.

18.   REPORTS. Individual accounts will be maintained for each participant in
the Plan. Statements of account will be given to participating Employees
promptly following the Purchase Date, which statements will set forth the
amounts of Contributions, the per share purchase price, the number of shares
purchased and the remaining cash balance, if any.

19.   ADJUSTMENTS UPON CHANGES IN CAPITALIZATION; CORPORATE TRANSACTIONS.

      (a)   Adjustment. Subject to any required action by the shareholders of
the Company, the number of shares of Common Stock covered by each option under
the Plan which has not yet been exercised and the number of shares of Common
Stock which have been authorized for issuance under the Plan but have not yet
been placed under option (collectively, the "Reserves"), as well as the price
per share of Common Stock covered by each option under the Plan which has not
yet been exercised, shall be proportionately adjusted for any increase or
decrease in the number of issued shares of Common Stock resulting from a stock
split, reverse stock split, stock dividend, combination or reclassification of
the Common Stock, or any other increase or decrease in the number of shares of
Common Stock effected without receipt of consideration by the Company; provided,
however, that conversion of any convertible securities of the Company shall not
be deemed to have been "effected without receipt of consideration". Such
adjustment shall be made by the Board, whose determination in that respect shall
be final, binding and conclusive. Except as expressly provided herein, no issue
by the Company of shares of stock of any class, or securities convertible into
shares of stock of any

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class, shall affect, and no adjustment by reason thereof shall be made with
respect to, the number or price of shares of Common Stock subject to an option.

      (b)   Corporate Transactions. In the event of the proposed dissolution or
liquidation of the Company, the Offering Period will terminate immediately prior
to the consummation of such proposed action, unless otherwise provided by the
Board. In the event of a proposed sale of all or substantially all of the assets
of the Company, or the merger of the Company with or into another corporation,
each option under the Plan shall be assumed or an equivalent option shall be
substituted by such successor corporation or a parent or subsidiary of such
successor corporation, unless the Board determines, in the exercise of its sole
discretion and in lieu of such assumption or substitution, to shorten the
Offering Period then in progress by setting a new Purchase Date (the "New
Purchase Date"). If the Board shortens the Offering Period then in progress in
lieu of assumption or substitution in the event of a merger or sale of assets,
the Board shall notify each participant in writing, at least ten (10) days prior
to the New Purchase Date, that the Purchase Date for his or her option has been
changed to the New Purchase Date and that his or her option will be exercised
automatically on the New Purchase Date, unless prior to such date he or she has
withdrawn from the Offering Period as provided in SECTION 10. For purposes of
this paragraph, an option granted under the Plan shall be deemed to be assumed
if, following the sale of assets or merger, the option confers the right to
purchase, for each share of option stock subject to the option immediately prior
to the sale of assets or merger, the consideration (whether stock, cash or other
securities or property) received in the sale of assets or merger by holders of
Common Stock for each share of Common Stock held on the effective date of the
transaction (and if such holders were offered a choice of consideration, the
type of consideration chosen by the holders of a majority of the outstanding
shares of Common Stock); provided, however, that if such consideration received
in the sale of assets or merger was not solely common stock of the successor
corporation or its parent (as defined in Section 424(e) of the Code), the Board
may, with the consent of the successor corporation and the participant, provide
for the consideration to be received upon exercise of the option to be solely
common stock of the successor corporation or its parent equal in fair market
value to the per share consideration received by holders of Common Stock and the
sale of assets or merger.

      The Board may, if it so determines in the exercise of its sole discretion,
also make provision for adjusting the Reserves, as well as the price per share
of Common Stock covered by each outstanding option, in the event that the
Company effects one or more reorganizations, recapitalizations, rights offerings
or other increases or reductions of shares of its outstanding Common Stock, and
in the event of the Company being consolidated with or merged into any other
corporation.

20.   AMENDMENT OR TERMINATION.

      (a)   The Board of Directors of the Company may at any time terminate or
amend the Plan. Except as provided in SECTION 19(b), no such termination may
affect options previously granted, nor may an amendment make any change in any
option theretofore granted which adversely affects the rights of any
participant. In addition, to the extent necessary to comply with Rule 16b-3
under the Exchange Act, or under Section 423 of the Code (or any successor rule
or provision or any applicable law or regulation), the Company shall obtain
shareholder approval in such a manner and to such a degree as so required.

      (b)   Without shareholder consent and without regard to whether any
participant rights may be considered to have been adversely affected, the Board
(or its committee) shall be entitled to change the Offering Periods and Purchase
Periods, limit the frequency and/or number of changes in the amount withheld
during an Offering Period, establish the exchange ratio applicable to amounts
withheld in a currency other than U.S. dollars, permit payroll withholding in
excess of the amount designated by a participant in order to adjust for delays
or mistakes in the Company's processing of properly completed withholding
elections, establish reasonable waiting and adjustment periods and/or accounting
and crediting procedures to ensure that amounts applied toward the purchase of
Common Stock for each participant properly correspond with amounts withheld from
the participant's Compensation, and establish such other limitations or
procedures as the Board (or its committee) determines in its sole discretion
advisable which are consistent with the Plan.

21.   NOTICES. All notices or other communications by a participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Company at the location, or by
the person, designated by the Company for the receipt thereof.

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22.   CONDITIONS UPON ISSUANCE OF SHARES. Shares shall not be issued with
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto shall comply with all applicable
provisions of law, domestic or foreign, including, without limitation, the
Securities Act of 1933, as amended, the Exchange Act, the rules and regulations
promulgated under those Acts, and the requirements of any stock exchange upon
which the shares may then be listed, and shall be further subject to the
approval of counsel for the Company with respect to such compliance. As a
condition to the exercise of an option, the Company may require the person
exercising such option to represent and warrant at the time of any such exercise
that the shares are being purchased only for investment and without any present
intention to sell or distribute such shares if, in the opinion of counsel for
the Company, such a representation is required by any of the aforementioned
applicable provisions of law.

23.   TERM OF PLAN; EFFECTIVE DATE. The Plan shall become effective upon the
earlier to occur of its adoption by the Board of Directors or its approval by
the shareholders of the Company. It shall continue in effect for a term of
twenty (20) years unless sooner terminated under SECTION 20.

24.   ADDITIONAL RESTRICTIONS OF RULE 16B-3. The terms and conditions of options
granted hereunder to, and the purchase of shares by, persons subject to Section
16 of the Exchange Act shall comply with the applicable provisions of Rule
16b-3. This Plan shall be deemed to contain, and such options shall contain, and
the shares issued upon exercise thereof shall be subject to, such additional
conditions and restrictions as may be required by Rule 16b-3 to qualify for the
maximum exemption from Section 16 of the Exchange Act with respect to Plan
transactions.

25.   PLAN APPROVAL. The Plan was initially approved by the Board and the
stockholders of the Company in the year 2000. In December 2002, the Board
approved an amendment and restatement of the Plan to provide (a) that a
participant may increase or decrease his or his percentage of payroll
withholding once during each Purchase Period, (b) that a participant may elect
to have payroll deductions made on each payday during an Offering Period in an
amount greater than or equal to zero percent (0%) but not more than fifteen
percent (15%) of the participant's Compensation and (c) for certain other
administrative changes, which amendments are not subject to stockholder
approval. The amendments described in the previous sentence shall be effective
for Offering Periods commencing on or after June 1, 2003. In May 2004, the Board
approved an amendment and restatement of the Plan to provide that all payroll
deductions credited to the account of a participant under the Plan shall accrue
interest subject to the provisions of Section 12 of the Plan, which amendment is
not subject to stockholder approval. The amendment described in the previous
sentence shall be effective for Offering Periods commencing on or after June 1,
2004.

                               * * * * * * * * * *

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                              CONNETICS CORPORATION
                        1995 EMPLOYEE STOCK PURCHASE PLAN
                    SUBSCRIPTION AGREEMENT FOR U.S. EMPLOYEES

1.    I, ________________________, hereby elect to participate in the CONNETICS
CORPORATION 1995 Employee Stock Purchase Plan (the "Plan") for the Offering
Period Offering Period ______________, 20___ to _______________, 20__, and
subscribe to purchase shares of the Company's Common Stock in accordance with
this Subscription Agreement and the Plan.

2.    I elect to have Contributions in the amount of ____% of my Compensation,
as those terms are defined in the Plan, applied to this purchase. I understand
that this amount must be greater than or equal to zero percent (0%) but not more
than fifteen percent (15%) of my Compensation during the Offering Period.
(PLEASE NOTE THAT NO FRACTIONAL PERCENTAGES ARE PERMITTED).

3.    I hereby authorize payroll deductions from each paycheck during the
Offering Period at the rate stated in Item 2 of this Subscription Agreement. I
understand that all payroll deductions made by me shall be credited to my
account under the Plan and that I may not make any additional payments into such
account. I understand that all payments made by me shall be accumulated for the
purchase of shares of Common Stock at the applicable purchase price determined
in accordance with the Plan. I further understand that, except as otherwise set
forth in the Plan, shares will be purchased for me automatically on the Purchase
Date of each Offering Period unless I otherwise withdraw from the Plan by giving
written notice to the Company for such purpose.

4.    I understand that I may discontinue at any time prior to the Purchase Date
my participation in the Plan as provided in Section 10 of the Plan. I also
understand that I can decrease the rate of my Contributions on one occasion only
during any Purchase Period by completing and filing a change of status notice
with such decrease taking effect for the first full payroll period commencing no
fewer than ten (10) business days following the Company's receipt the change of
status notice, unless this change is processed more quickly. Further, I may
change the rate of deductions for future Offering Periods by filing a new
Subscription Agreement, and any such change will be effective as of the
beginning of the next Offering Period. In addition, I acknowledge that, unless I
discontinue my participation in the Plan as provided in Section 10 of the Plan,
my election will continue to be effective for each successive Offering Period.

5.    I have received a copy of the Company's most recent description of the
Plan and a copy of the complete "CONNETICS CORPORATION 1995 Employee Stock
Purchase Plan." I understand that my participation in the Plan is in all
respects subject to the terms of the Plan.

6.    Shares purchased for me under the Plan should be issued in the name(s) of
(name of employee or employee and spouse only):

                       __________________________________

                       __________________________________

7.    In the event of my death, I hereby designate the following as my
beneficiary(ies) to receive all payments and shares due to me under the Plan:

NAME: _____________________________________         ____________________
(Please print) (First) (Middle) (Last)                   (Relationship)

__________________________________
             (Address)

__________________________________

                                      -1-
<PAGE>

8.    I understand that if I dispose of any shares received by me pursuant to
the Plan within two years after the Offering Date (the first day of the Offering
Period during which I purchased such shares) or within one year after the
Purchase Date, I will be treated for federal income tax purposes as having
received ordinary compensation income at the time of such disposition in an
amount equal to the excess of the fair market value of the shares on the
Purchase Date over the price which I paid for the shares, regardless of whether
I disposed of the shares at a price less than their fair market value at the
Purchase Date. The remainder of the gain or loss, if any, recognized on such
disposition will be treated as capital gain or loss.

      I hereby agree to notify the Company in writing within 30 days after the
date of any such disposition, and I will make adequate provision for federal,
state or other tax withholding obligations, if any, which arise upon the
disposition of the Common Stock. The Company may, but will not be obligated to,
withhold from my compensation the amount necessary to meet any applicable
withholding obligation including any withholding necessary to make available to
the Company any tax deductions or benefits attributable to the sale or early
disposition of Common Stock by me.

9.    If I dispose of such shares at any time after expiration of the 2-year and
1-year holding periods, I understand that I will be treated for federal income
tax purposes as having received compensation income only to the extent of an
amount equal to the lesser of (1) the excess of the fair market value of the
shares at the time of such disposition over the purchase price which I paid for
the shares under the option, or (2) 15% of the fair market value of the shares
on the Offering Date. The remainder of the gain or loss, if any, recognized on
such disposition will be treated as capital gain or loss.

      I understand that this tax summary is only a summary and is subject to
change. I further understand that I should consult a tax advisor concerning the
tax implications of the purchase and sale of stock under the Plan.

10.   I hereby agree to be bound by the terms of the Plan. The effectiveness of
this Subscription Agreement is dependent upon my eligibility to participate in
the Plan.

SIGNATURE: ____________________________________

SOCIAL SECURITY OR TAX I.D. #: _______________________

DATE: _______________________

SPOUSE'S SIGNATURE (necessary if beneficiary is not spouse):

____________________________________________________________
(Signature)

____________________________________
(Print name)

                                      -2-
<PAGE>

                              CONNETICS CORPORATION
                        1995 EMPLOYEE STOCK PURCHASE PLAN
                 SUBSCRIPTION AGREEMENT FOR AUSTRALIAN EMPLOYEES

1.    I, ________________________, hereby elect to participate in the CONNETICS
CORPORATION 1995 Employee Stock Purchase Plan (the "Plan") for the Offering
Period Offering Period ______________, 20___ to _______________, 20__, and
subscribe to purchase shares of the Company's Common Stock in accordance with
this Subscription Agreement and the Plan.

2.    I elect to have Contributions in the amount of ____% of my Compensation,
as those terms are defined in the Plan, applied to this purchase. I understand
that this amount must be greater than or equal to zero percent (0%) but not more
than fifteen percent (15%) of my Compensation during the Offering Period.
(PLEASE NOTE THAT NO FRACTIONAL PERCENTAGES ARE PERMITTED).

3.    I hereby authorize payroll deductions from each paycheck during the
Offering Period at the rate stated in Item 2 of this Subscription Agreement. I
understand that all payroll deductions made by me shall be credited to my
account under the Plan and that I may not make any additional payments into such
account. I understand that all payments made by me shall be accumulated for the
purchase of shares of Common Stock at the applicable purchase price determined
in accordance with the Plan. I further understand that, except as otherwise set
forth in the Plan, shares will be purchased for me automatically on the Purchase
Date of each Offering Period unless I otherwise withdraw from the Plan by giving
written notice to the Company for such purpose.

4.    I understand that I may discontinue at any time prior to the Purchase Date
my participation in the Plan as provided in Section 10 of the Plan. I also
understand that I can decrease the rate of my Contributions on one occasion only
during any Purchase Period by completing and filing a change of status notice
with such decrease taking effect for the first full payroll period commencing no
fewer than ten (10) business days following the Company's receipt the change of
status notice, unless this change is processed more quickly. Further, I may
change the rate of deductions for future Offering Periods by filing a new
Subscription Agreement, and any such change will be effective as of the
beginning of the next Offering Period. In addition, I acknowledge that, unless I
discontinue my participation in the Plan as provided in Section 10 of the Plan,
my election will continue to be effective for each successive Offering Period.

5.    I have received a copy of the Company's most recent description of the
Plan and a copy of the complete "CONNETICS CORPORATION 1995 Employee Stock
Purchase Plan." I understand that my participation in the Plan is in all
respects subject to the terms of the Plan.

6.    Shares purchased for me under the Plan should be issued in the name(s) of
(name of employee or employee and spouse only):

                     _____________________________________

                     _____________________________________

7.    In the event of my death, I hereby designate the following as my
beneficiary(ies) to receive all payments and shares due to me under the Plan:

NAME: _____________________________________         ____________________
(Please print) (First) (Middle) (Last)                   (Relationship)

__________________________________
             (Address)

__________________________________

                                      -1-
<PAGE>

      I understand that the tax summary in the Explanatory Booklet is only a
summary and is subject to change. I further understand that I should consult a
tax advisor concerning the tax implications of the purchase and sale of stock
under the Plan.

10.   I hereby agree to be bound by the terms of the Plan. The effectiveness of
this Subscription Agreement is dependent upon my eligibility to participate in
the Plan.

SIGNATURE: ____________________________________

SOCIAL SECURITY OR TAX I.D. #: _____________________________

DATE: _____________________________

SPOUSE'S SIGNATURE (necessary if beneficiary is not spouse):

____________________________________________________________
(Signature)

____________________________________________________________
(Print name)

                                      -2-
<PAGE>

                              CONNETICS CORPORATION
                        1995 EMPLOYEE STOCK PURCHASE PLAN
                             CHANGE OF STATUS NOTICE


  [ ] WITHDRAWAL FROM 1995 EMPLOYEE STOCK PURCHASE PLAN

I, __________________________, hereby elect to withdraw my participation in the
CONNETICS CORPORATION 1995 Employee Stock Purchase Plan (the "Plan") for the
Offering Period ______________, 20___ to _______________, 20__. This withdrawal
covers all Contributions credited to my account and is effective on the date
designated below.

I understand that all Contributions credited to my account will be paid to me
within ten (10) business days of receipt by the Company of this Notice of
Withdrawal and that my option for the current period will automatically
terminate, and that no further Contributions for the purchase of shares can be
made by me during the Offering Period.

I further understand and agree that I shall be eligible to participate in
succeeding Offering Periods only by delivering to the Company a new Subscription
Agreement.

If the undersigned is an Officer or Director of CONNETICS CORPORATION or other
person subject to Section 16 of the Securities Exchange Act of 1934, the
signature below indicates that, in addition to the foregoing, I understand that
under rules promulgated by the U.S. Securities and Exchange Commission I may not
re-enroll in the Plan for a period of six (6) months after withdrawal.


  [ ] CHANGE IN PAYROLL DEDUCTION

I, __________________________, hereby elect to change my rate of payroll
deduction under the Plan as follows. I elect to have Contributions in the amount
of ____% of my Compensation, as those terms are defined in the Plan, applied
toward the purchase of shares under the Plan. I understand that this amount must
be greater than or equal to zero percent (0%) but not more than fifteen percent
(15%) of my Compensation during the Offering Period. (PLEASE NOTE THAT NO
FRACTIONAL PERCENTAGES ARE PERMITTED).

An increase or a decrease in payroll deduction will be effective for the first
full payroll period commencing no fewer than ten (10) business days following
the Company's receipt of this notice, unless this change is processed more
quickly.

                                       2
<PAGE>


  [ ] CHANGE OF BENEFICIARY

This change of beneficiary shall terminate my previous beneficiary designation
under the Plan. In the event of my death, I hereby designate the following as my
beneficiary(ies) to receive all payments and shares due to me under the Plan:

NAME: _____________________________________         ____________________
(Please print) (First) (Middle) (Last)                   (Relationship)

__________________________________
             (Address)

__________________________________

SIGNATURE: ____________________________________

SOCIAL SECURITY OR TAX I.D. #: _____________________________

DATE: _____________________________

SPOUSE'S SIGNATURE (necessary if beneficiary is not spouse):

____________________________________________________________
(Signature)

_______________________________________
(Print name)

                                       2