MANNATECH, INCORPORATED 2008 STOCK INCENTIVE PLAN STOCK OPTION AWARD CERTIFICATE

Exhibit 10.3

Stock Option Award (#)              

MANNATECH, INCORPORATED

2008 STOCK INCENTIVE PLAN

STOCK OPTION AWARD CERTIFICATE

THIS IS TO CERTIFY that Mannatech, Incorporated, a Texas corporation (the “ Company ”), has granted you (the “ Participant ”) an option to purchase Common Stock (the “ Stock ” or “ Shares ”) of the Company under its 2008 Stock Incentive Plan (the “ Plan ”), as follows:

By your signature and the signature of the Company’s representative below, you and the Company agree to be bound by all of the terms and conditions of the Stock Option Agreement, which is attached hereto as Annex I and the Plan (both incorporated herein by this reference as if set forth in full in this document). By executing this Certificate, you hereby irrevocably elect to accept the Stock Option Award rights granted pursuant to this Certificate and the related Stock Option Agreement and to receive the Option to purchase Stock of the Company designated above subject to the terms of the Plan, this Certificate and the Stock Option Agreement.

Mannatech, Incorporated Stock Option Award Certificate

Annex I

MANNATECH, INCORPORATED

2008 STOCK INCENTIVE PLAN

STOCK OPTION AGREEMENT

This Stock Option Agreement (this “ Agreement ”), is made and entered into on the execution date of the Stock Option Award Certificate to which it is attached (the “ Certificate ”), by and between Mannatech, Incorporated, a Texas corporation (the “ Company ”), and the Director, Employee or Consultant (“ Participant ”) named in the Certificate.

Pursuant to the Mannatech, Incorporated 2008 Stock Incentive Plan (the “ Plan ”), the Administrator of the Plan has authorized the grant to Participant of the option to purchase shares of the Company’s Common Stock (the “ Award ”), upon the terms and subject to the conditions set forth in the Certificate, this Agreement and the Plan. Capitalized terms not otherwise defined herein shall have the meanings ascribed to them in the Plan.

NOW , THEREFORE , in consideration of the premises and the benefits to be derived from the mutual observance of the covenants and promises contained herein and other good and valuable consideration, the sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

1. Grant of Option . The Company hereby grants to Participant an option (this “ Option ”) to purchase the total number of shares of Common Stock of the Company set forth in the Certificate as “Total Option Shares” (the “ Shares ”) at the” Exercise Price Per Share” set forth in the Certificate (the “ Exercise Price ”), subject to all of the terms and conditions of the Certificate, this Agreement and the Plan. If designated as an Incentive Stock Option in the Certificate, the Option is intended to qualify as an “incentive stock option” (an “ ISO ”) within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended (the “ Code ”), although the Company makes no representation or guarantee that such Option will qualify as an ISO.

2. Exercise Period; Vesting . Unless expired as provided in Section 3 of this Agreement, this Option may be exercised from time to time after the Date of Grant set forth in the Certificate to the extent the Option has vested in accordance with the vesting schedule set forth in the Certificate. The Shares issued upon exercise of the Option will be subject to the restrictions on transfer set forth in Section 10 below. Provided Participant continues to provide Continuous Service to the Company or any Affiliate, the Option will become vested according to the Vesting Schedule in the Certificate. A vested Option may not be exercised for less than a full share. If application of the vesting percentage causes a fractional Share to otherwise become exercisable, such Share shall be rounded down to the nearest whole Share for each year except for the last year in such vesting period, at the end of which vesting period this Option shall become exercisable for the full remainder of the unexercised Shares subject to the Option.

3. Expiration . The Option shall expire on the Expiration Date set forth in the Certificate or earlier as provided in Section 4 below.

Mannatech, Incorporated Stock Option Agreement

4. Termination of Continuous Service .

4.1. Forfeiture of Unvested Options . If the Participant’s Continuous Service is terminated for any reason, the unvested portion of the Option shall terminate as set forth in this Section 4.1 and the Participant may exercise the vested portion as provided in this Section 4 . Unless otherwise provided in the Plan or an employment agreement the terms of which have been approved by the Administrator, outstanding Options that are not exercisable at the time the Participant’s Continuous Service terminates for any reason other than Cause (including upon the Participant’s death or Disability) shall be forfeited and expire at the close of business on the date of such termination. If the Participant’s Continuous Service is terminated as a result of the Participant’s termination for Cause, all outstanding Options granted to the Participant (whether or not vested), shall be forfeited and expire as of the beginning of business on the date of such termination for Cause.

4.2. Termination for Any Reason Except Death, Disability or Cause . Unless otherwise provided in an employment agreement the terms of which have been approved by the Administrator, if Participant’s Continuous Service is terminated for any reason, except death, Disability or Cause, the Option, to the extent (and only to the extent) that it would have been exercisable by Participant as of the date of termination of Continuous Service, may be exercised by Participant only within such period of time ending on the earlier of the Expiration Date or, except as set forth in Section 4.5 , the date that is three (3) months following the termination of the Participant’s Continuous Service and the Option shall thereafter terminate and cease to be exercisable. If, after termination the Option is not exercised within the time specified herein, the Option shall terminate.

4.3. Termination Because of Death or Disability . If Participant’s Continuous Service is terminated because of the death or Disability of Participant (or Participant dies within three (3) months of the date of termination when such termination is for any reason other than Participant’s Disability or for Cause), the Option, to the extent that is exercisable by Participant on the date of termination, may be exercised by Participant (or by the Participant’s estate, by a person who acquired the right to exercise the Option by bequest or inheritance or by a person designated to exercise the Option upon the Participant’s death) no later than twelve (12) months after the date of termination, but in any event no later than the Expiration Date. If after such termination of Continuous Service the Option is not exercised within the time specified herein, the Option shall terminate.

4.4. Termination for Cause . If the Participant’s Continuous Service is terminated as a result of the Participant’s termination for Cause, all outstanding Options granted to such Participant (whether or not vested), shall be forfeited and expire as of the beginning of business on the date of such termination for Cause.

4.5. Extension of Termination Date . If the exercise of the Option following the termination of the Participant’s Continuous Service for any reason other than Cause (other than upon the Participant’s death or Disability) would be prohibited at any time solely because the exercise of the Option or issuance of Shares of Common Stock would violate the registration requirements under the Securities Act or any other state or federal securities law or the rules of any securities exchange or interdealer quotation system, then the Option shall terminate on the

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earlier of (a) the expiration of the Expiration Date specified in the Certificate or (b) the expiration of a period after termination of the Participant’s Continuous Service that is three (3) months after the end of the period during which the exercise of the Option would be in violation of such registration or other securities law requirements.

4.6. No Obligation to Employ . Nothing in the Plan or this Agreement shall confer on Participant any right to continue in the employ of, or other relationship with, the Company or any Affiliate, or limit in any way the right of the Company or any Affiliate to terminate Participant’s employment or other relationship at any time, with or without Cause.

5. Manner of Exercise .

5.1. Stock Option Exercise Agreement . To exercise this Option, Participant (or in the case of exercise after Participant’s death or incapacity, Participant’s executor, administrator, heir or legatee, as the case may be) must deliver to the Company an executed stock option exercise agreement in the form attached hereto as Exhibit A , or in such other form as may be approved by the Administrator from time to time (the “ Exercise Agreement ”), which shall set forth, inter alia , (a) Participant’s election to exercise the Option, (b) the number of Shares being purchased, (c) any restrictions imposed on the Shares and (d) any representations warranties and agreements regarding Participant’s investment intent and access to information as may be required by the Company to comply with applicable securities laws. If someone other than Participant exercises the Option, then such person must submit documentation reasonably acceptable to the Company verifying that such person has the legal right to exercise the Option.

5.2. Limitations on Exercise . The Option may not be exercised unless such exercise is in compliance with all applicable federal and state securities laws, as they are in effect on the date of exercise. The Option may not be exercised for fewer than one (1) Share or for a fractional Share. If a fractional Share would otherwise become exercisable, such Share shall be rounded down to the nearest whole Share for each year except for the last year of the applicable vesting period, at the end of which vesting period this Option shall become exercisable for the full remainder of the unexercised Shares subject to the Option.

5.3. Payment . The entire Exercise Price of this Option to purchase Shares issued under the Plan (plus applicable tax withholding) shall be payable in full by cash, wire, or certified or bank check for an amount equal to the aggregate Exercise Price Per Share for the number of Shares being purchased. Alternatively, in the sole discretion of the Plan Administrator and upon such terms as the Plan Administrator shall approve, the Exercise Price may be paid by:

(a) paying all or a portion of the aggregate Exercise Price Per Share for the number of Shares being purchased by delivery to the Company of other shares of Common Stock, duly endorsed for transfer to the Company, with a Fair Market Value on the date of delivery equal to the exercise price (or portion thereof) due for the number of Shares being acquired, or by means of attestation whereby the Participant identifies for delivery specific shares of Common Stock where such shares have a Fair Market Value on the date of attestation equal to the exercise price (or portion thereof) and receives a number of Shares equal to the difference between the number of Shares thereby purchased and the number of identified

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attestation shares of Common Stock (collectively a “Stock For Stock Exercise” ); provided, however, that the shares of Common Stock used in such Stock for Stock Exercise (i) have either (1) been held for more than six (6) months (or such longer or shorter period of time required to avoid a charge to earnings for financial accounting purposes) and have been paid for within the meaning of SEC Rule 144 (and, if such shares were purchased from the Company by use of a promissory note, such note has been fully paid with respect to such shares); or (2) were obtained by Participant in the open public market; and (ii) are clear of all liens, claims, encumbrances or security interests. Payment of the Exercise Price by a Participant who is an officer, director or other “insider” subject to Section 16(b) of the Exchange Act in the form of a Stock for Stock Exercise is subject to pre-approval by the Administrator, in its sole discretion, in a manner that complies with the specificity requirements of Rule 16b-3 under the Exchange Act, including the name of the Participant involved in the transaction,