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                                                                    EXHIBIT 4.1


                               AMENDMENT NO. 8 TO
                                     TEKELEC
                             1994 STOCK OPTION PLAN


     1. Section 3. Section 3 of the Tekelec 1994 Stock Option Plan is hereby
amended to read in its entirety as follows:

          "3. SHARES RESERVED.

               The maximum aggregate number of Shares reserved for issuance
          pursuant to the Plan shall be Twenty One Million Eight Hundred
          Thousand (21,800,000) Shares or the number of shares of stock to which
          such Shares shall be adjusted as provided in Section 10 of the Plan.
          Such number of Shares may be set aside out of authorized but unissued
          Shares not reserved for any other purpose, or out of issued Shares
          acquired for and held in the treasury of the Company from time to
          time.

               Shares subject to, but not sold or issued under, any Option
          terminating, expiring or canceled for any reason prior to its exercise
          in full, shall again become available for Options thereafter granted
          under the Plan, and the same shall not be deemed an increase in the
          number of Shares reserved for issuance under the Plan."

     2. Section 4.b. Section 4.b. of the 1994 Stock Option Plan is hereby
amended to read in its entirety as follows:

               "b. Subject to the provisions of the Plan, the Committee shall
          have the authority, in its discretion: (i) to grant Incentive Stock
          Options, in accordance with Section 422 of the Code, or Non-Statutory
          Stock Options; (ii) to determine, upon review of relevant information,
          the Fair Market Value per Share; (iii) to determine the exercise price
          of the Options to be granted to Employees in accordance with Section
          6(c) of the Plan; (iv) to determine the Employees to whom, and the
          time or times at which, Options shall be granted, and the number of
          Shares subject to each Option; (v) to prescribe, amend and rescind
          rules and regulations relating to the Plan subject to the limitations
          set forth in Section 12 of the Plan; (vi) to determine the terms and
          provisions of each Option granted to Optionees under the Plan and each
          Option Agreement (which need not be identical with the terms of other
          Options and Option Agreements) and, with the consent of the Optionee,
          to modify or amend an outstanding Option or Option Agreement,
          provided, however, that the Committee shall not have the authority to
          amend or adjust the exercise price of any Options previously granted
          to an Optionee under the Plan, whether through amendment,
          cancellation, replacement grant or otherwise; (vii) to accelerate the
          exercise date of any Option; (viii) to determine whether any Optionee
          will be required to execute a stock repurchase agreement or other
          agreement as a condition to the exercise of an Option, and to
          determine the terms and provisions








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          of any such agreement (which need not be identical with the terms of
          any other such agreement) and, with the consent of the Optionee, to
          amend any such agreement; (ix) to interpret the Plan or any agreement
          entered into with respect to the grant or exercise of Options, to
          determine the eligibility of an Employee for benefits hereunder and
          the amount thereof; (x) to authorize any person to execute on behalf
          of the Company any instrument required to effectuate the grant of an
          Option previously granted or to take such other actions as may be
          necessary or appropriate with respect to the Company's rights pursuant
          to Options or agreements relating to the grant or exercise thereof;
          and (xi) to make such other determinations and establish such other
          procedures as it deems necessary or advisable for the administration
          of the Plan."


Dated:  March 23, 2000