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Exhibit 10.1

BENTLEY PHARMACEUTICALS, INC.

2005 EQUITY AND INCENTIVE PLAN

1.     Establishment and Purpose

        The Bentley Pharmaceuticals, Inc. 2005 Equity and Incentive Plan (the
"Plan") is a successor to the following equity compensation plans:

(i)Bentley Pharmaceuticals, Inc. Amended and Restated 1991 Stock Option Plan
(the "1991 Plan");

(ii)2001 Employee Stock Option Plan of Bentley Pharmaceuticals, Inc. (the "2001
Plan"); and

(iii)2001 Directors' Stock Option Plan of Bentley Pharmaceuticals, Inc. (the
"Directors' Plan").

        The 1991 Plan, the 2001 Plan, and the Directors' Plan are sometimes
collectively referred to herein as the "Prior Plans". Effective as of the date
the Plan is approved by the Company's stockholders (the "Effective Date"), no
further options shall be granted under the Prior Plans. However, the provisions
of the Prior Plans shall continue to apply to options granted under the Prior
Plans prior to the Effective Date. In the event that the Plan is not approved by
the stockholders, options shall continue to be granted under the Prior Plans in
accordance with their terms, to the extent permissible thereunder.

        The purpose of the Plan is to attract and retain key employees,
consultants, and directors of the Company and its Affiliates, to provide an
incentive for them to achieve long-range performance goals, and to enable them
to participate in the long-term growth of the Company. The Plan seeks to achieve
this purpose by providing Awards in the form of Restricted Stock, Restricted
Stock Units, Cash Awards, Options (which may constitute Incentive Stock Options
or Nonstatutory Stock Options) or Stock Appreciation Rights.

2.     Definitions

        Capitalized terms are defined in the provisions of the Plan or in
Appendix 1 attached hereto, which is incorporated in the Plan by this reference.
Appendix 1 also contains a list of defined terms and reference to where their
definitions appear in the Plan.

3.     Administration

        The Plan shall be administered by the Committee. The Committee shall
determine which eligible employees, consultants, and directors will receive
Awards. The Committee shall have authority to adopt, alter and repeal such
administrative rules, guidelines and practices governing the operation of the
Plan as it shall from time to time consider advisable, to interpret the
provisions of the Plan and any Award agreement, and to remedy any ambiguities or
inconsistencies therein. The Committee's decisions shall be final and binding.
To the extent permitted by applicable law, the Committee may delegate to one or
more executive officers of the Company the power to make Awards to Participants
who are not subject to Section 16 of the Exchange Act and all determinations
under the Plan with respect thereto, provided that the Committee shall fix the
maximum amount of such Awards for all such Participants and a maximum for any
one Participant, and such other features of the Awards as required by applicable
law.

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4.     Eligibility

        All employees, directors and consultants of the Company or any Affiliate
are eligible to be Participants in the Plan. Incentive Stock Options may be
granted only to eligible employees of the Company or its Affiliates who are
taxpayers for United States federal income tax purposes.

5.     Stock Available for Awards

        (a)   Amount.    Shares of Common Stock available for grants of Awards
under the Plan shall consist of (i) all shares of Common Stock remaining
available on the Effective Date for grant of options under the Prior Plans,
(ii) all shares of Common Stock subject to any outstanding option under any of
the Prior Plans or the Executive Options that after the Effective Date expires,
terminates unexercised, or is forfeited or settled in a manner that results in
fewer shares outstanding than were subject to the option as originally granted,
and (iii) all additional shares that may become available as a result of any
adjustment under Section 5(b). Not more than 5,166,828 shares shall become
available under the Plan pursuant to clauses (i) and (ii) of the preceding
sentence. If any Award under the Plan expires, is terminated unexercised, or is
forfeited or settled in a manner that results in fewer shares outstanding than
were originally awarded, then any shares no longer subject to such Award and not
issued thereunder shall again be available for Awards under the Plan. Common
Stock issued through the assumption or substitution of outstanding grants from
an acquired company shall not reduce the shares available for Awards under the
Plan. Shares issued under the Plan may consist in whole or in part of authorized
but unissued shares or treasury shares.

        (b)   Adjustment.    In the event that the Committee determines that any
stock dividend, extraordinary cash dividend, recapitalization, reorganization,
merger, consolidation, split-up, spin-off, combination, exchange of shares, or
other transaction affects the Common Stock such that an adjustment is required
in order to preserve the benefits intended to be provided by the Plan, then the
Committee (subject in the case of Incentive Stock Options to any limitation
required under the Code) shall equitably adjust any or all of (i) the number and
kind of shares in respect of which Awards may be made under the Plan, (ii) the
number and kind of shares subject to outstanding Awards, and (iii) the exercise
price with respect to any of the foregoing, and if considered appropriate, the
Committee may make provision for a cash payment with respect to an outstanding
Award, provided that the number of shares subject to any Award shall always be a
whole number.

        (c)   Limit on Individual Grants.    The maximum number of shares of
Common Stock subject to all Awards that may be granted under the Plan to any
Participant in the aggregate in any calendar year shall not exceed 500,000
shares subject to adjustment under subsection (b). With respect to any Award
settled in cash that is intended to satisfy the requirements for
"performance-based compensation" (within the meaning of Section 162(m)(4)(C) of
the Code), no more than $5,000,000 may be paid to any one individual with
respect to each year of a Performance Period.

6.     Stock Options

        (a)   Grant of Options.    Subject to the provisions of the Plan, the
Committee may grant options ("Options") to purchase shares of Common Stock
(i) complying with the requirements of Section 422 of the Code or any successor
provision and any regulations thereunder ("Incentive Stock Options"), and
(ii) not intended to comply with such requirements ("Nonstatutory Stock
Options"). The Committee shall determine the number of shares subject to each
Option and the exercise price therefor, which shall not be less than 100% of the
Fair Market Value of the Common Stock on the date of grant.

        (b)   Terms and Conditions.    Each Option shall be exercisable at such
times and subject to such terms and conditions as the Committee may specify in
the applicable grant or thereafter; provided that (i) no Option shall be
exercisable after the expiration of ten years from the date the Option is
granted, and (ii) no Option may be granted with a reload feature which provides
for an automatic grant of

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additional or replacement options upon the exercise of an Option. The Committee
may impose such conditions with respect to the exercise of Options, including
conditions relating to applicable securities laws, as it considers necessary or
advisable.

        (c)   Payment.    No shares shall be delivered pursuant to any exercise
of an Option until payment in full of the exercise price therefor is received by
the Company. Such payment may be made in whole or in part in cash or to the
extent permitted by the Committee at or after the grant of the Option, pursuant
to any of the following methods: (i) by actual delivery and transfer, or
attestation of ownership and delivery of a valid instrument of transfer, to the
Company of shares of Common Stock owned by the Participant, including vested
Restricted Stock, (ii) by retaining shares of Common Stock otherwise issuable
pursuant to the Option, (iii) for consideration received by the Company under a
broker-assisted cashless exercise program acceptable to the Company, or (iv) for
such other lawful consideration as the Committee may determine.

7.     Stock Appreciation Rights

        (a)   Grant of SARs.    Subject to the provisions of the Plan, the
Committee may grant rights to receive any excess in value of shares of Common
Stock over the exercise price ("Stock Appreciation Rights" or "SARs") in tandem
with an Option (at or after the award of the Option), or alone and unrelated to
an Option. SARs in tandem with an Option shall terminate to the extent that the
related Option is exercised, and the related Option shall terminate to the
extent that the tandem SARs are exercised. The Committee shall determine at the
time of grant or thereafter whether SARs are settled in cash, Common Stock or
other securities of the Company, Awards or other property.

        (b)   Exercise Price.    The Committee shall fix the exercise price of
each SAR or specify the manner in which the price shall be determined. An SAR
granted in tandem with an Option shall have an exercise price not less than the
exercise price of the related Option. An SAR granted alone and unrelated to an
Option may not have an exercise price less than 100% of the Fair Market Value of
the Common Stock on the date of the grant.

        (c)   Limited SARs.    An SAR related to an Option, which SAR can only
be exercised upon or during limited periods following a change in control of the
Company, may entitle the Participant to receive an amount based upon the highest
price paid or offered for Common Stock in any transaction relating to the change
in control or paid during a specified period immediately preceding the
occurrence of the change in control in any transaction reported in the stock
market in which the Common Stock is normally traded.

8.     Restricted Stock and Restricted Stock Units

        (a)   Grant of Restricted Stock.    Subject to the provisions of the
Plan, the Committee may grant shares of Common Stock subject to forfeiture
("Restricted Stock") and determine the duration of the period (the "Restricted
Period") during which, and the conditions under which, the shares may be
forfeited to the Company and the other terms and conditions of such Awards.
Shares of Restricted Stock may be issued for no cash consideration or such
minimum consideration as may be required by applicable law.

        (b)   Restrictions.    Shares of Restricted Stock may not be sold,
assigned, transferred, pledged or otherwise encumbered, except as permitted by
the Committee, during the Restricted Period. Shares of Restricted Stock shall be
evidenced in such manner as the Committee may determine. Any certificates issued
in respect of shares of Restricted Stock shall be registered in the name of the
Participant and unless otherwise determined by the Committee, deposited by the
Participant, together with a stock power endorsed in blank, with the Company. At
the expiration of the Restricted Period, the Company shall deliver such
certificates to the Participant or, if the Participant has died, to the
Participant's Designated Beneficiary.

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        (c)   Restricted Stock Units.    Subject to the provisions of the Plan,
the Committee may grant the right to receive in the future shares of Common
Stock subject to forfeiture ("Restricted Stock Units") and determine the
duration of the Restricted Period during which, and the conditions under which,
the Award may be forfeited to the Company and the other terms and conditions of
such Awards. Restricted Stock Unit Awards shall constitute an unfunded and
unsecured obligation of the Company, and shall be settled in shares of Common
Stock or cash, as determined by the Committee at the time of grant or
thereafter. Such Awards shall be made in the form of "units" with each unit
representing the equivalent of one share of Common Stock.

9.     General Provisions Applicable to Awards

        (a)   Transferability.    Except as otherwise provided in this
Section 9(a), an Award (i) shall not be transferable other than as designated by
the Participant by will or by the laws of descent and distribution, and (ii) may
be exercised during the Participant's lifetime only by the Participant or by the
Participant's guardian or legal representative. In the discretion of the
Committee, any Award may be transferable upon such terms and conditions and to
such extent as the Committee determines at or after grant, provided that
Incentive Stock Options may be transferable only to the extent permitted by the
Code.

        (b)   Documentation.    Each Award under the Plan shall be evidenced by
a writing delivered to the Participant specifying the terms and conditions
thereof and containing such other terms and conditions not inconsistent with the
provisions of the Plan as the Committee considers necessary or advisable to
achieve the purposes of the Plan or to comply with applicable tax and regulatory
laws and accounting principles.

        (c)   Committee Discretion.    Each type of Award may be made alone, in
addition to or in relation to any other Award. The terms of each type of Award
need not be identical, and the Committee need not treat Participants uniformly.
In addition to the authority granted to the Committee in Section 9(l) to make
Awards to Covered Employees which qualify as "performance-based compensation"
for purposes of Section 162(m) of the Code, the Company may grant Awards subject
to such performance conditions (including performance-based vesting) as it shall
determine in its discretion. Except as otherwise provided by the Plan or a
particular Award, any determination with respect to an Award may be made by the
Committee at the time of grant or at any time thereafter.

        (d)   Dividends and Cash Awards.    In the discretion of the Committee,
any Award under the Plan may provide the Participant with (i) dividends or
dividend equivalents payable currently or deferred with or without interest, and
(ii) cash payments in lieu of or in addition to an Award.

        (e)   Termination of Employment or Service.    The Committee shall
determine and set forth in the grant agreement evidencing the Award the effect
on an Award of the disability, death, retirement or other termination of
employment or service of a Participant and the extent to which, and the period
during which, the Participant's legal representative, guardian or Designated
Beneficiary may receive payment of an Award or exercise rights thereunder.
Unless the Committee provides otherwise in any case, a Participant's employment
or service shall have terminated for purposes of the Plan at the time the entity
by which the Participant is employed or to which the Participant renders service
ceases to be an Affiliate of the Company.

        (f)    Change in Control.    In order to preserve a Participant's rights
under an Award in the event of a change in control of the Company as defined by
the Committee (a "Change in Control"), the Committee in its discretion may, at
the time an Award is made or at any time thereafter, take one or more of the
following actions: (i) provide for the acceleration of any time period relating
to the exercise or payment of the Award, (ii) provide for payment to the
Participant of cash or other property with a Fair Market Value equal to the
amount that would have been received upon the exercise or payment of the Award
had the Award been exercised or paid upon the Change in Control, (iii) adjust

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the terms of the Award in a manner determined by the Committee to reflect the
Change in Control, (iv) cause the Award to be assumed, or new rights substituted
therefor, by another entity, or (v) make such other provision as the Committee
may consider equitable to Participants and in the best interests of the Company.

        (g)   Loans.    Except for loans to reporting Persons, which are not
authorized hereunder, the Committee may authorize the making of loans to
Participants in connection with the grant or exercise of any Award under the
Plan.

        (h)   Withholding Taxes.    The Participant shall pay to the Company, or
make provision satisfactory to the Committee for payment of, any taxes required
by law to be withheld in respect of Awards under the Plan no later than the date
of the event creating the tax liability. In the Committee's discretion, such tax
obligations may be paid in whole or in part in shares of Common Stock, including
shares retained from the Award creating the tax obligation, valued at their Fair
Market Value on the date of delivery. The Company and its Affiliates may, to the
extent permitted by law, deduct any such tax obligations from any payment of any
kind otherwise due to the Participant.

        (i)    Foreign National Awards.    Notwithstanding anything to the
contrary contained in the Plan, Awards may be made to Participants who are
foreign nationals or employed or performing services outside the United States
on such terms and conditions different from those specified in the Plan as the
Committee considers necessary or advisable to achieve the purposes of the Plan
or to comply with applicable laws.

        (j)    Amendment of Award.    Except as provided in Section 9(k), the
Committee may amend, modify or terminate any outstanding Award, including
substituting therefor another Award of the same or a different type, changing
the date of exercise or realization, and converting an Incentive Stock Option to
a Nonstatutory Stock Option, provided that the Participant's consent to such
action shall be required unless (i) the Committee determines that the action,
taking into account any related action, would not materially and adversely
affect the Participant, or (ii) the action is permitted by the terms of the
Plan.

        (k)   No Repricing of Options.    Notwithstanding anything to the
contrary in the Plan, the Company shall not engage in any repricing of Options
granted under the Plan (including those granted under the Prior Plans and the
Executive Options) without further stockholder approval. For this purpose, the
term "repricing" shall mean any of the following or other action that has the
same effect: (i) lowering the exercise price of an Option after it is granted,
(ii) any other action that is treated as a repricing under generally accepted
accounting principles, or (iii) canceling an Option at a time when its exercise
price exceeds the fair market value of the underlying stock in exchange for
another Option, Restricted Stock, or other equity of the Company, unless the
cancellation and exchange occurs in connection with a merger, acquisition,
spin-off, or similar corporate transaction.

        (l)    Code Section 162(m) Provisions.    If the Committee determines at
the time an Award is granted to a Participant that such Participant is, or may
be as of the end of the tax year for which the Company would claim a tax
deduction in connection with such Award, a Covered Employee, then the Committee
may provide that the Participant's right to receive cash, Shares, or other
property pursuant to such Award shall be subject to the satisfaction of
Performance Goals during a Performance Period. Prior to the payment of any Award
subject to this Section 9(l), the Committee shall certify in writing that the
Performance Goals and other material terms applicable to such Award were
satisfied. Notwithstanding the attainment of Performance Goals by a Covered
Employee, the Committee shall have the right to reduce (but not to increase) the
amount payable at a given level of performance to take into account additional
factors that the Committee may deem relevant. The Committee shall have the power
to impose such other restrictions on Awards subject to this Section 9(l) as it
may deem necessary or appropriate to ensure that such Awards satisfy all
requirements for "performance-based compensation" within the meaning of
Section 162(m) of the Code.

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10.   Miscellaneous

        (a)   No Right To Employment.    No person shall have any claim or right
to be granted an Award. Neither the Plan nor any Award hereunder shall be deemed
to give any employee the right to continued employment or service or to limit
the right of the Company to discharge any Participant at any time.

        (b)   No Rights As Stockholder.    Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any rights
as a stockholder with respect to any shares of Common Stock to be distributed
under the Plan until he or she becomes the holder thereof. A Participant to whom
Common Stock is awarded shall be considered the holder of the Stock at the time
of the Award except as otherwise provided in the applicable Award.

        (c)   Effective Date.    The Plan shall become effective on the
Effective Date.

        (d)   Amendment and Term of Plan.    The Board may amend, suspend or
terminate the Plan or any portion thereof at any time, subject to such
stockholder approval as the Board determines to be necessary or advisable to
comply with any tax or regulatory requirement. Unless terminated earlier by the
Board or extended by subsequent approval of the Company's stockholders, the term
of the Plan shall expire at the close of business on the date immediately
preceding the tenth anniversary of the date on which the Plan was originally
approved by stockholders, and no further Awards shall be made thereafter.

        (e)   Governing Law.    The provisions of the Plan shall be governed by
and interpreted in accordance with the laws of Delaware.

The Plan was adopted by the Board of Directors on March 30, 2005.

The Plan was approved by the stockholders on May 24, 2005.

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Appendix 1

        "1991 Plan"—See Section 1.

        "2001 Plan"—See Section 1.

        "Affiliate" means any business entity in which the Company owns directly
or indirectly 50% or more of the total voting power or has a significant
financial interest as determined by the Committee.

        "Award" means any Option, Stock Appreciation Right, Restricted Stock,
Restricted Stock Unit, Cash Award, or Foreign National Award granted under the
Plan.

        "Board" means the Board of Directors of the Company.

        "Cash Award"—See Section 9(d).

        "Code" means the Internal Revenue Code of 1986, as amended from time to
time, or any successor law.

        "Committee" means one or more committees each comprised of not less than
three members of the Board appointed by the Board to administer the Plan or a
specified portion thereof. If a Committee is authorized to grant Awards to a
Reporting Person or a Covered Employee, each member shall be a "disinterested
person" or the equivalent within the meaning of applicable Rule 16b-3 under the
Exchange Act or an "outside director" or the equivalent within the meaning of
Section 162(m) of the Code, respectively.

        "Common Stock" or "Stock" means the Common Stock, $.02 par value, of the
Company.

        "Company" means Bentley Pharmaceuticals, Inc.

        "Covered Employee" means a "covered employee" within the meaning of
Section 162(m) of the Code.

        "Designated Beneficiary" means the beneficiary designated by a
Participant, in a manner determined by the Committee, to receive amounts due or
exercise rights of the Participant in the event of the Participant's death. In
the absence of an effective designation by a Participant, "Designated
Beneficiary" means the Participant's estate.

        "Directors' Plan"—See Section 1.

        "Effective Date"—See Section 1.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended
from time to time, or any successor law.

        "Executive Options"—means options granted and approved by Bentley
stockholders in 1996 to Bentley's then executive officers, Messrs. Murphy, Price
and Stote, outside of any stock option plan.

        "Fair Market Value" means, with respect to Common Stock or any other
property, the fair market value of such property as determined by the Committee
in good faith or in the manner established by the Committee from time to time.

        "Foreign National Award"—See Section 9(i).

        "Incentive Stock Option"—See Section 6(a).

        "Nonstatutory Stock Option"—See Section 6(a).

        "Option"—See Section 6(a).

        "Participant" means a person selected by the Committee to receive an
Award under the Plan.

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        "Performance Goals" means with respect to any Performance Period, one or
more objective performance goals based on one or more of the following objective
criteria established by the Committee prior to the beginning of such Performance
Period or within such period after the beginning of the Performance Period as
shall meet the requirements to be considered "pre-established performance goals"
for purposes of Code Section 162(m): (i) increases in the price of the Common
stock, (ii) market share, (iii) sales, (iv) revenue, (v) return on equity,
assets, or capital, (vi) economic profit (economic value added), (vii) total
shareholder return, (viii) costs, (ix) expenses, (x) margins, (xi) earnings or
earnings per share, (xii) cash flow, (xiii) customer satisfaction,
(xiv) operating profit, (xv) research and development, (xvi) product
development, (xvii) manufacturing, or (xviii) any combination of the foregoing,
including without limitation, goals based on any of such measures relative to
appropriate peer groups or market indices. Such Performance Goals may be
particular to a Participant or may be based, in whole or in part, on the
performance of the Company generally or on the performance of the division,
department, line of business, subsidiary, or other business unit, whether or not
legally constituted, in which the Participant works.

        "Performance Period" means the period of service designated by the
Committee applicable to an Award subject to Section 9(l) for which the
Performance Goals will be measured.

        "Plan" means the Bentley Pharmaceuticals, Inc. 2005 Equity and Incentive
Plan.

        "Prior Plans"—See Section 1.

        "Reporting Person" means a person subject to reporting under Section 16
of the Exchange Act.

        "Restricted Period"—See Section 8(a).

        "Restricted Stock"—See Section 8(a).

        "Restricted Stock Unit"—See Section 8(c)

        "Stock Appreciation Right" or "SAR"—See Section 7(a).

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QuickLinks

Exhibit 10.1

BENTLEY PHARMACEUTICALS, INC. 2005 EQUITY AND INCENTIVE PLAN
Appendix 1