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                                                                    EXHIBIT 10.8



                               AMENDMENT NO. 1 TO
                                     TEKELEC
                             OFFICER SEVERANCE PLAN


                  Section(d) of the Tekelec Officer Severance Plan is hereby
amended to read in its entirety as follows:

                  "(d) (i) If in connection with, or within two years following,
                  a Change in Control of the Company, (A) an Eligible Officer's
                  employment with the Company (or the Acquiror) is terminated by
                  the Company (or the Acquiror) without Cause or (B) an Eligible
                  Officer terminates his/her employment with the Company (or the
                  Acquiror) for "Good Reason," then all of such Eligible
                  Officer's then unvested options and other rights to purchase
                  or acquire securities or other property of the Company or the
                  Acquiror (including but not limited to any options or rights
                  assumed by the Acquiror in connection with the Change in
                  Control), other than any such options or rights that were
                  granted after the effective date of the Change in Control,
                  shall automatically vest and become immediately exercisable in
                  full and all of such Eligible Officer's options and rights to
                  purchase securities or other property of the Company and/or
                  the Acquiror (other than any such options and rights that are
                  granted after the effective date of the Change in Control,
                  which options and rights shall be governed by the terms
                  thereof) shall be exercisable for a period of one year
                  following the effective date of such Eligible Officer's
                  termination of employment with the Company or the Acquiror, as
                  the case may be (notwithstanding any terms or provisions to
                  the contrary in any applicable stock option plan, stock option
                  agreement or other plan or agreement); provided, however, that
                  any such option or other right shall not be exercisable after
                  the expiration of the term of such option or other right set
                  forth in the option agreement or other agreement evidencing
                  such right.

                           (ii) If in connection with a Change in Control of the
                  Company described in Section 2(e)(iii) of this Plan, an
                  Eligible Officer is not offered, at least ten days prior to
                  the effective date of such Change in Control, employment with
                  the Acquiror after the effective date of the Change in Control
                  on terms and conditions generally no less favorable to the
                  Eligible Officer than the terms and conditions of his/her

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                  employment in effect with the Company immediately prior to the
                  effective date of the Change in Control, then all of such
                  Eligible Officer's unvested options and other rights to
                  purchase or acquire the Company's securities that are
                  outstanding immediately prior to the effective date of the
                  Change in Control shall automatically vest and become
                  immediately exercisable in full and all of such Eligible
                  Officer's options and rights to purchase or acquire the
                  Company's securities that are outstanding immediately prior to
                  the effective date of the Change in Control shall be
                  exercisable for a period of one year following the effective
                  date of such Change in Control (notwithstanding any terms or
                  provisions to the contrary in any applicable stock option
                  plan, stock option agreement or other plan or agreement);
                  provided, however, that any such option or other right shall
                  not be exercisable after the expiration of the term of such
                  option or other right set forth in the option agreement or
                  other agreement evidencing such right."



Dated:   March 8, 1999