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                                                                    EXHIBIT 14.2

                              CONNETICS CORPORATION
              CODE OF PROFESSIONAL CONDUCT FOR BOARD OF DIRECTORS,
                  CHIEF EXECUTIVE AND SENIOR FINANCIAL OFFICERS

Connetics' Code of Conduct includes a set of business values that guide all of
our decisions and behavior. One of our core values is that all employees are
expected to exhibit, and will be held to, the highest standards of integrity. We
are honest and ethical in all our business dealings, starting with how we treat
each other. We strive to keep our promises and admit our mistakes. We are
committed to ensuring that Connetics' name is always worthy of trust.

This Code of Professional Conduct applies to Connetics' Board of Directors and
to "Senior Financial Officers" of Connetics. "Senior Financial Officers" are
those employees who have financial reporting responsibilities, including
specifically the Chief Executive Officer, Chief Financial Officer, and
Controller. Directors and the Senior Financial Officers hold an important and
elevated role in corporate governance in that they are uniquely capable and
empowered to ensure that all stakeholders' interests are appropriately balanced,
protected and preserved through our financial controls and disclosures. This
Code of Professional Conduct supplements the company-wide Code of Conduct, and
the Senior Financial Officers are expected to abide by this Code as well as all
applicable Connetics business conduct standards and policies or guidelines in
our employee handbook relating to areas covered by this Code.

OBLIGATIONS.

Connetics' Directors and Senior Financial Officers must, to the best of their
knowledge and ability:

         1.       Engage in and promote honest and ethical conduct, including
                  the ethical handling of actual or apparent conflicts of
                  interest between personal and professional relationships;

         2.       Avoid conflicts of interest and disclose to the Compliance
                  Officer any material transaction or relationship that could
                  reasonably be expected to give rise to such a conflict.
                  Specifically, Directors and Senior Financial Officers may not
                  compete with Connetics and may never let business dealings on
                  behalf of Connetics be influenced - or even appear to be
                  influenced - by personal or family interests;

         3.       Take all reasonable measures (a) to protect the
                  confidentiality of non-public information about Connetics and
                  its customers obtained or created in connection with the
                  business, and (b) to prevent the unauthorized disclosure of
                  such information unless required by applicable law or
                  regulation or legal or regulatory process;

         4.       Ensure that Connetics' accounting records are maintained in
                  accordance with all applicable laws, are proper, supported and
                  classified, and do not contain any false or misleading
                  entries.

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         5.       Produce full, objective, fair, accurate, timely and
                  understandable financial disclosure in reports and documents
                  that Connetics files with, or submits to, the Securities and
                  Exchange Commission and other regulators and in other public
                  communications made by Connetics;

         6.       Comply with Regulation FD in the dissemination of material
                  information, and comply with all other applicable governmental
                  laws, rules and regulations, as well as the rules and
                  regulations of self-regulatory organizations of which
                  Connetics is a member;

         7.       Achieve responsible use, control, and stewardship over all
                  Connetics' assets and resources that are employed or entrusted
                  to the Board or the Senior Financial Officers; and

         8.       Promptly report any possible violation of this Code of
                  Professional Conduct to the Compliance Officer or any of the
                  parties or channels listed below.

PROHIBITIONS.

Connetics' Directors and Senior Financial Officers are prohibited from directly
or indirectly taking any action to fraudulently influence, coerce, manipulate or
mislead Connetics' independent public auditors for the purpose of rendering the
financial statements of Connetics misleading.

RESPONSIBILITIES.

Connetics' Senior Financial Officers are responsible for the Company's system of
internal financial controls. Directors and Senior Financial Officers shall
promptly bring to the attention of the General Counsel and the Audit Committee
any information they may have concerning:

                  (a)      significant deficiencies in the design or operation
                           of internal controls that could adversely affect the
                           Company's ability to record, process, summarize and
                           report financial data;

                  (b)      any fraud, whether or not material, that involves
                           management or other employees who have a significant
                           role in the Company's financial reporting,
                           disclosures or internal controls; or

                  (c)      any actual or apparent conflicts of interest between
                           personal and professional relationships, involving
                           any management or other employees who have a
                           significant role in the Company's financial
                           reporting, disclosures or internal controls.

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ACCOUNTABILITY.

Connetics' Directors and Senior Financial Officers will be held accountable for
their adherence to this Code of Professional Conduct. Failure to observe the
terms of this Code may result in disciplinary action, up to and including
termination of employment. Violations of this Code may also constitute
violations of law and may result in civil and criminal penalties for the
Directors, the Senior Financial Officers and their supervisors, and/or
Connetics.

AMENDMENT/WAIVER.

This Code cannot be substantively amended and no part of it can be waived except
by a vote of the Board of Directors or a designated committee, which will
ascertain whether an amendment or waiver is appropriate and ensure that the
amendment or waiver is accompanied by appropriate controls designed to protect
Connetics. If any substantive amendment is made or any waiver is granted, the
waiver will be posted on Connetics' website, which will allow our stockholders
to evaluate the merits of the particular waiver.

HOTLINE.

Anyone who has a concern about a questionable accounting or auditing matter and
wishes to submit the concern confidentially or anonymously, may do so by

         (1)      calling the Reporting Hotline 24-hour number at
                  1-877-841-3303;

         (2)      sending an e-mail to http://www.connetics.com\hotline, or

         (3)      sending a letter to:

                  Connetics Corporation
                  c/o MessagePeople-1006
                  PO Box 1164
                  Newark, CA 94560

Connetics will handle all inquiries discretely and make every effort to
maintain, within the limits allowed by law, the confidentiality of anyone
requesting guidance or reporting questionable behavior and/or a compliance
concern.

SARBANES-OXLEY ACT OF 2002.

It is Connetics' intention that this Code of Professional Conduct be its written
code of ethics under Section 406 of the Sarbanes-Oxley Act of 2002 complying
with the standards set forth in Securities and Exchange Commission Regulation
S-K Item 406.

                                  *****END*****

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