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                                                                      Exhibit 10

                            JONES PHARMA INCORPORATED
           1999 EQUITY PARTICIPATION PLAN FOR NON-MANAGEMENT DIRECTORS

     1.   PURPOSE. The purpose of this 1999 Equity Participation Plan is to
provide certain long-term equity incentives to eligible directors of the Company
in order to encourage the highest level of performance of non-management
directors by providing those directors with a proprietary interest in the
Company's success and progress through grants of options to purchase shares of
the Company's Common Stock and other equity-based awards in accordance with the
terms and conditions set forth below.

     2.   DEFINITIONS. Whenever used herein, the following shall have the
meanings set forth below:

     (a)  "Affiliate" refers to any corporation or other entity which directly,
or through one or more intermediaries, controls, is controlled by, or is under
common control with the Company.


     (b)  "Board" shall mean the Board of Directors of the Company.

     (c)  "Common Stock" shall mean the common stock of the Company.

     (d)  "Company" shall mean Jones Pharma Incorporated.

     (e)  "Eligible Director" shall mean an individual who is a member of the
Board and who is not at the time of the grant, an employee of the Company or any
subsidiary of the Company.

     (f)  "Exchange Act" shall mean the Securities Exchange Act of 1934, as
amended.

     (g)  "FSO Plan" shall mean the 1994 Formula Stock Option Plan for
non-management directors of the Company.

     (h)  "Formula Stock Option" shall mean an option granted to an Eligible
Director pursuant to Section 6 of this Plan.

     (i)  "Initial Exercise Date" with respect to any Formula Stock Option shall
mean the date which is eleven (11) months following the date on which an
Eligible Director becomes a Participant in this Plan.

     (j)  "Option Period" with respect to any Formula Stock Option shall mean
the period of time during which a Participant may exercise his Formula Stock
Option as more specifically set forth in paragraph (d) of Section 6 of this
Plan.

     (k)  "Option Price" with respect to any Formula Stock Option or any option
right provided in any Other Award shall mean the price per share of Common Stock
at which a


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Participant may purchase Common Stock and shall be subject to adjustment as
provided in Section 4(c) below.

     (l)  "Option Shares" shall mean the shares of Common Stock which are
subject to any stock option granted or awarded pursuant to this Plan, whether or
not a Formula Stock Option and the number of Option Shares shall be subject to
adjustment as provided in Section 4(c) below.

     (m)  "Other Award" means an equity-based incentive award granted under this
Plan other than a Formula Stock Option.

     (n)  "Participant" shall mean an Eligible Director to whom a Formula Stock
Option or Other Award has been granted pursuant to this Plan.

     (o)  "Plan" means this 1999 Equity Participation Plan for Non-Management
Directors.

     (p)  "Termination of Service" is the date as of which (i) the service of a
director as a member of the Board is discontinued because of the death, removal,
resignation or expiration of term without re-election, or (ii) a director
becomes an employee of the Company or any Affiliate of the Company, whichever is
the first to occur.

     (q)  "Year of Service" with respect to any Formula Stock Option means each
continuous twelve (12) month period following the Initial Exercise Date during
which a Participant serves as a director of the Company.

     3.   ADMINISTRATION. This Plan shall, to the extent necessary, be
administered by the President of the Company, or such other person or persons as
may be appointed by the President (the "Administrator"). The Administrator shall
take such action necessary so as to comply with the provisions of this Plan. The
grant of a Formula Stock Option shall be evidenced by the execution of a Formula
Stock Option Agreement in the form of Exhibit A attached hereto executed by each
Participant. Grants of Other Awards must be approved by (i) a majority of the
entire Board of Directors and (ii) a majority of those members of the Board of
Directors who are not Eligible Directors.

     4.   SHARES AVAILABLE FOR FORMULA STOCK OPTIONS AND OTHER AWARDS.

     (a)  There is hereby reserved for issuance under this Plan an aggregate of
150,000 shares of Common Stock, subject to adjustment as provided in paragraph
(c) of this Section 4.

     (b)  In the event of a lapse, expiration, termination or cancellation of
any Formula Stock Options or Other Awards granted under this Plan without the
issuance of shares of Common Stock, the shares subject to or reserved for such
Formula Stock Options or Other Awards (including any shares of Common Stock
forfeited and returned to the Company under the terms of any such Other Award)
may again be used for new grants and awards hereunder; provided that in no event
may the number of shares issued under this Plan exceed the total number of
shares reserved for issuance in accordance with paragraph (a) of this Section 4.



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     (c)  In the event of a reorganization, recapitalization, stock split, stock
dividend, combination of shares, merger, consolidation, rights offering, or any
other change in the corporate structure or shares of Common Stock of the
Company, an equitable adjustment shall be made in the number and kind of shares
authorized by this Plan, and in the number and kind of shares covered by any
Formula Stock Options or Other Awards granted so that the position of each
Participant after such transaction will be equivalent to his relative position
prior to such transaction including, in the case of any Formula Stock Option or
any stock option forming a part of any Other Award, an appropriate adjustment in
the Option Price per share.

     5.   ELIGIBILITY. The individuals who are eligible to receive Formula Stock
Options or any Other Award hereunder shall be limited to Eligible Directors. An
Eligible Director of the Company shall become a Participant in this Plan on the
first day of the month following the date (subsequent to the Effective Date of
this Plan set forth in Section 13) on which said Eligible Director is elected or
appointed to the Board (whether elected by shareholders of the Company or
appointed by the Board itself to fill a vacancy on the Board).

     6.   GRANT OF FORMULA STOCK OPTIONS.

     (a)  Grant to Participants. Each Eligible Director shall be granted a
Formula Stock Option on the day that said Eligible Director becomes a
Participant as provided in Section 5, provided, however, that no Eligible
Director shall be awarded a Formula Stock Option under this Plan (i) if such
Eligible Director has previously been granted, and currently holds any unvested
Formula Stock Options pursuant to the FSO Plan or this Plan, or (ii) if such
Eligible Director has previously been granted and holds any Other Award under
this Plan as to which all vesting or service contingencies relating to such
Other Award shall not have been fulfilled.

     (b)  Option Price. The Option Price per share of Common Stock with respect
to each Formula Stock Option shall be equal to the fair market value of the
Common Stock on the date that the Formula Stock Option is granted. During any
period in which the Common Stock is listed for trading on a registered national
securities exchange or on the NASDAQ National Market System, the fair market
value shall be equal to the lower of (i) the closing price, and (ii) the average
of the high and low prices (or the average of the low bid and high asked prices,
as appropriate), on the date of grant.

     (c)  Option Shares. The number of Option Shares subject to each Formula
Stock Option granted to a Participant shall be Fifteen Thousand (15,000) shares
of Common Stock subject to adjustment pursuant to the provisions of paragraph
(c) of Section 4. Each Formula Stock Option shall be subject to the vesting
provisions set forth in Section 7 below.

     (d)  Option Period. Each Formula Stock Option must be exercised, if at all,
on or before the first to occur of (i) the date that is ninety (90) days after
the effective date of the Termination of Service of a Participant, provided,
however, that if the Termination of Service is a result of the death of a
director or is a result of a director becoming an employee of the Company or any
Affiliate, then two hundred eighty (280) days after the date of such Termination
of Service and (ii) the fifth anniversary of the Initial Exercise Date, at which
time the entire





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Formula Stock Option granted to such Participant (or such portion thereof that
has not been exercised) shall lapse, terminate and be of no further force and
effect.

     (e)  Payment. The Option Price shall be payable in cash by the Participant
at the time the Formula Stock Option is exercised, provided, however, that if
the Company permits "exchange exercise" features with respect to option plans
for employees, such "exchange exercise" features shall be applicable to options
granted under this Plan also. No shares shall be issued until full payment
therefore has been made. A grantee of a Formula Stock Option shall have none of
the rights of a shareholder of the Company until the shares are issued.

     7.   EXERCISE OF FORMULA STOCK OPTIONS.

     During the Option Period, a Formula Stock Option shall vest and may be
exercised at the times and in the amounts as follows: (i) twenty percent (20%)
of the Option Shares may be purchased by the Participant at any time during the
period commencing with the Initial Exercise Date and ending on the last day of
the Option Period; and (ii) an additional twenty percent (20%) of the Option
Shares may be purchased by the Participant for each Year of Service of said
Participant following the Initial Exercise Date during the Option Period.

     8.   OTHER AWARDS.

     The Board of Directors is authorized under this Plan to grant and award
other equity incentives to Eligible Directors based upon the Company's Common
Stock, provided, however, that no such Other Award shall be issued to any
Eligible Director who holds an outstanding unvested Formula Stock Option under
this Plan or under the 1994 FSO Plan unless such unvested option is waived and
forfeited by written agreement between the Company and the Eligible Director.
Any such Other Award may take the form of an option to purchase shares of the
Company's Common Stock having an expiration date not more than ten years from
the date of grant or may take the form of restricted share grants or of stock
appreciation rights payable in cash or in stock, provided that all contingencies
associated with any such Other Award are to be fully resolved within not more
than ten years from the date of grant.

     9.   THE DISCONTINUANCE OR AMENDMENT OF PLAN. The Board may discontinue
this Plan at any time and may from time to time amend or revise the terms of the
Plan as permitted by applicable statutes, except that it may not revoke or
alter, in any manner unfavorable to Plan Participants, any Formula Stock Options
or Other Awards outstanding, nor may the Board amend this Plan without
shareholder approval, where the absence of such approval would cause this Plan
to fail to comply with Rule 16b-3 under the Exchange Act, or any other
requirement of applicable law or regulation. Furthermore, the provisions of this
Plan shall not be amended more than once every six months, other than to comport
with changes in the Internal Revenue Code of 1986, as amended (the "Code"), the
Employee Retirement Income Security Act, or the rules thereunder.

     No Formula Stock Option or Other Award shall be granted under this Plan
after June 30, 2009, but Formula Stock Options and Other Awards granted
theretofore may extend beyond that date is accordance with their terms



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     10.  NON-TRANSFERABILITY. No Formula Stock Option or Other Award granted
under this Plan shall be transferable other than by will or the laws of descent
and distribution and shall be exercisable, during the grantee's lifetime, only
by the grantee or the grantee's guardian or legal representative.

     11.  NO RIGHT OF DIRECTORSHIP. Nothing in this Plan shall be deemed to
create any obligation on the part of the Board to nominate any director for
re-election as a director by the shareholders of the Company nor to create any
right to continue as a director of the Company.

     12.  RESTRICTION ON RESALE OF STOCK. Each Formula Stock Option or Other
Award issued hereunder shall be subject to the requirement that if at any time
the Administrator shall determine, in his discretion, that the listing,
registration or qualification of the shares subject to the Formula Stock Option
or Other Award upon any securities exchange or under any state or federal law,
or the consent or approval of any governmental regulatory body is necessary or
desirable as a condition of, or in connection with, the granting of such option
or the issue or purchase of shares thereunder, such Formula Stock Option or
Other Award may not be exercised in whole or in part unless and until such
listing, registration, qualification, consent or approval shall have been
effected or obtained free of any conditions not acceptable to the Administrator.
Certificates representing shares of stock issued pursuant to this Plan shall
bear the following legend unless the shares have been registered under the
referenced laws:

     "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933
     AS AMENDED OR APPLICABLE STATE SECURITIES LAWS AND MAY NOT BE TRANSFERRED
     WITHOUT AN OPINION OF COUNSEL SATISFACTORY IN FORM AND SUBSTANCE TO THE
     COMPANY THAT SUCH TRANSFER MAY BE LAWFULLY EFFECTED IN THE ABSENCE OF SUCH
     REGISTRATION."

     13.  EFFECTIVE DATE. This Plan shall be effective as of July 13, 1999.

     14.  EXPENSES OF PLAN. The expenses of this Plan shall be borne by the
Company.

     15.  SHAREHOLDER APPROVAL OF FORMULA STOCK OPTION GRANTS. Any other
provision of this Plan notwithstanding, no Formula Stock Option shall be issued
pursuant hereto prior to the ratification of such grants by holders of a
majority of the outstanding Common Stock of the Company at an annual or special
meeting of the shareholders of the Company. Any failure of the shareholders to
ratify the issuance of Formula Stock Options hereunder shall not affect any
Other Awards authorized hereunder, whether such authorization occurs prior or
subsequent to the vote on ratification of Formula Stock Option grants.







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