<PAGE>   1
                                                                     Exhibit 4.D


THE SECURITIES REPRESENTED BY THIS STOCK PURCHASE WARRANT HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"),
OR ANY STATE SECURITIES LAWS. THEY MAY NOT BE OFFERED FOR SALE OR SOLD EXCEPT
PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AS TO THE SECURITIES UNDER THE
SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS OR AN APPLICABLE
EXEMPTION FROM SUCH REGISTRATION REQUIREMENTS.


                                                        NO._____________________
                                               Commencing Date: October 17, 1997
                                               Expiration Date: October 17, 2000

                             STOCK PURCHASE WARRANT

                            TO PURCHASE COMMON SHARES
                                       OF
                                   ZILA, INC.

THIS CERTIFIES that, for value received (the "INVESTOR") is entitled to
subscribe for and purchase from Zila, Inc., incorporated under the laws of the
State of Delaware (hereinafter called the "COMPANY"), at the price of $9.915 per
share, subject to adjustment as provided herein (the "EXERCISE PRICE") at any
time during the three year period commencing OCTOBER 17, 1997 and ending OCTOBER
17, 2000 up to ____________ fully paid and non-assessable shares of Common Stock
of the Company, par value ($.001) per share (hereinafter called "COMMON STOCK"),
subject, however, to the provisions and upon the terms and conditions
hereinafter set forth; provided, however, that in no event shall the holder be
entitled to exercise this Warrant to the extent that (a) the number of shares of
Common Stock beneficially owned by such holder and its affiliates (other than
shares of Common Stock which may be deemed beneficially owned through the
ownership of the unexercised portion of this Warrant or the unexercised or
unconverted portion of any other securities of the Company (including the
Company's Series A Redeemable Convertible Preferred Stock) subject to a
limitation on conversion or exercise analogous to the limitation contained
herein) and (b) the number of shares of Common Stock issuable upon exercise of
this Warrant (or portion thereof) with respect to which the determination
described herein is being made, would result in beneficial ownership by such
holder and its affiliates of more than 4.99% of the outstanding shares of Common
Stock. For purposes of the immediately preceding sentence, beneficial ownership
shall be determined in accordance with Section 13(d) of the Securities Exchange
Act of 1934, as amended, and Regulation 13D-G thereunder, except as otherwise
provided in clause (a) hereof. Except as provided in the immediately succeeding
sentence, the restrictions set forth above in this paragraph may not be amended
without the consent of the holder of this Warrant and the holders of a majority
of the Company's then outstanding Common Stock. The holder hereof may waive the
restrictions set forth above by written notice to the Company upon not less than
sixty one (61) days prior notice (with such waiver taking effect only upon the
expiration of such sixty one (61) day notice period).
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      This Warrant is one of the Warrants (the "WARRANTS") issued pursuant to
Section 1 of that certain Securities Purchase Agreement dated as of October __,
1997, among the Company and the Buyers referred to therein (the "PURCHASE
AGREEMENT").

      The resale of the shares of Common Stock or other securities issuable upon
exercise or exchange of this Warrant is subject to the provisions of the
Registration Rights Agreement of even date herewith (the "REGISTRATION RIGHTS
AGREEMENT") by and between the Company and the Investor, as well as applicable
federal and state securities laws.

1. (a) The rights represented by this warrant may be exercised by the holder
hereof, in whole or part (but not as to a fractional share of Common Stock), by
delivery of written notice in the form of Exhibit A attached hereto, the
surrender of this Warrant (properly endorsed if required) at the office of the
Company (or such other office or agency of the Company as it may designate by
notice in writing to the holder hereof at the address of such holder appearing
on the books of the Company at any time within the period above named) and upon
payment to it by certified check, cashiers check or wire transfer of the
Exercise Price of such shares. In the event of any exercise of the rights
represented by this Warrant, certificates for the shares of Common Stock as
purchased shall be delivered to the holder hereof at the Company's expense
(including, without limitation, the payment by it of any applicable stock
transfer or stock issuance tax) within three (3) business days, after the rights
represented by this Warrant shall have been so exercised, and, unless this
Warrant has expired, a new Warrant representing the number of shares of Common
Stock, if any, with respect to which this Warrant shall not then have been
exercised shall also be issued to the holder hereof within such time. The holder
thereof shall be deemed for all corporate purposes to have become the holder of
record of such shares of Common Stock immediately prior to the close of business
on the date on which the Warrant is surrendered and payment of the amount due in
respect of such exercise and any applicable taxes is made, irrespective of the
date of delivery of certificates evidencing such shares of Common Stock, except
that, if the date of such surrender and payment is a date when the stock
transfer books of the Company are properly closed, such person shall be deemed
to have become the holder of such Warrant Shares at the opening of business on
the next succeeding date on which the stock transfer books are open. In the
event that the exercise of this Warrant, in full or in part, would result in the
issuance of any fractional shares of Common Stock, then in such event the number
of shares to be issued shall be rounded up or down to the nearest whole share
and no fractional shares shall be issued.

      (b) In the case of a dispute as to the determination of the Exercise Price
of this Warrant or the last reported sale price (as reported by Bloomberg) of a
security or the arithmetic calculation of the shares of Common Stock to be
received upon exercise, the Company shall promptly issue to the holder the
number of shares of Common Stock that is not disputed and shall submit the
disputed determinations or arithmetic calculations to the holder via facsimile
within one business day of receipt of the holder's subscription notice. If the
holder and the Company are unable to agree upon any such disputed item within
one day of such disputed determination or arithmetic calculation being submitted
to the holder,


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then the Company shall immediately submit via facsimile the disputed
determination or arithmetic calculation to its independent, outside accountant.
The Company shall cause the accountant to perform the determinations or
calculations and notify the Company and the holder of the results no later than
forty-eight (48) hours from the time it receives the disputed determinations or
calculations. Such or accountant's determination shall be deemed conclusive
absent manifest error.

      (c) If the Company shall fail for any reason or for no reason to issue to
the holder on a timely basis as described in this Section 1, a certificate for
the number of shares of Common Stock to which the holder is entitled upon the
holder's exercise of this Warrant or a new Warrant for the number of shares of
Common Stock to which such holder is entitled pursuant to paragraph 1(a) hereof,
the Company shall, in addition to any other remedies under this Warrant or the
Purchase Agreement or otherwise available to such holder, including any
indemnification under Section 8 of the Purchase Agreement, pay as additional
damages in cash to such holder on each day that such exercise is not timely
effected in an amount equal to 1% of the product of (A) the sum of the number of
shares of Common Stock not issued to the holder on a timely basis and to which
the holder is entitled and, in the event the Company has failed to timely
deliver a new Warrant, the number of shares represented by the portion of this
Warrant which is not being converted, as the case may be, and (B) the highest
Closing Bid Price (as defined in the Company's Certificate of Designations) of
the Company's Common Stock from the time the holder delivered its exercise
notice to the Company to the time the Company properly delivers such shares of
Common Stock to the holder.

      (d) The Company will not, by amendment of its Certificate of Incorporation
or through any reorganization, transfer of assets, consolidation, merger,
dissolution, issue or sale of securities, or any other voluntary action, avoid
or seek to avoid the observance or performance of any of the terms to be
observed or performed by it hereunder, but will at all times in good faith
assist in the carrying out of all the provisions of this Warrant and in the
taking of all such action as may reasonably be requested by the holder of this
Warrant in order to protect the exercise privilege of the holder of this Warrant
against dilution or other impairment, consistent with the tenor and purpose of
this Warrant. No impairment of the designations, preferences and rights of the
Preferred Shares contained in the Company's Certificate of Designations or any
waiver thereof which has an adverse effect on the rights granted hereunder shall
be given effect until the Company has taken appropriate action (satisfactory to
the holders of all of the Warrants) to avoid such adverse effect with respect to
this Warrant. Without limiting the generality of the foregoing, the Company (i)
will not increase the par value of any shares of Common Stock receivable upon
the exercise of this Warrant above the Exercise Price then in effect, and (ii)
will take all such actions as may be necessary or appropriate in order that the
Company may validly and legally issue fully paid and nonassessable shares of
Common Stock upon the exercise of this Warrant.

2. The Company represents and warrants that this Warrant has been duly
authorized and validly issued and is enforceable against the Company in
accordance with its terms (except as such enforceability may be limited by
bankruptcy, insolvency or other laws affecting


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<PAGE>   4
creditors' rights, whether at law or in equity). The Company covenants and
agrees that all shares of Common Stock which may be issued upon the exercise of
the rights represented by this Warrant will, upon issuance, be fully paid and
non-assessable and free of from taxes, liens and charges with respect to the
issue thereof (other than taxes in respect of any transfer occurring
contemporaneously with such issue). The Company further covenants and agrees
that during the period within which the rights represented by this Warrant may
be exercised, the Company will at all times have authorized, and reserved, a
sufficient number of shares of Common Stock to provide for the exercise of the
rights represented by this Warrant and will at its expense expeditiously upon
each such reservation of shares procure the listing thereof (subject to issuance
of notice of issuance) on all stock exchanges, if any, on which such shares are
then listed. The Company further covenants and agrees that the Company shall
maintain the listing of any shares of Common Stock issuable upon the exercise of
this Warrant if and so long as any Warrant is outstanding or any shares of
Common Stock issued upon exercise of any Warrant are held by an Investor or any
transferee of an Investor (unless the Common Stock is de-listed pursuant to
Section 3(g) of the Certificate of Designations).

3.       The above provisions are, however, subject to the following:

         (a) In the event that the Company shall declare any dividend or other
distribution upon its outstanding Common Stock payable in Common Stock or shall
subdivide its outstanding shares of Common Stock into a greater number of
shares, then the number of shares of Common Stock which may thereafter be
purchased upon the exercise of the rights represented hereby shall be increased
in proportion to the increase through such dividend or subdivision and the
Exercise Price per share shall be decreased in such proportion. In the event
that the Company shall at any time combine the outstanding shares of its Common
Stock into a smaller number of shares, the number of shares of Common Stock
which may thereafter be purchased upon the exercise of the rights represented
hereby shall be decreased in proportion to the decrease through such combination
and the Exercise Price per share shall be increased in such proportion.

         (b) In the event that the Company shall declare a dividend upon the
Common Stock payable otherwise than out of earnings or surplus (other than
paid-in surplus) or otherwise than in Common Stock, the Exercise Price per share
in effect immediately prior to the declaration of such dividend shall be reduced
by an amount equal, in the case of a dividend in cash, to the amount thereof
payable per share of the Common or, in the case of any other dividend, to the
fair value thereof share of the Common Stock as determined by the Board of
Directors of the Company. For the purposes of the foregoing a dividend other
than in cash shall be considered payable out of earnings or surplus (other
paid-in surplus) only to the extent that such earnings or surplus are charged an
amount equal to the fair value of such dividend as determined by the Board of
Directors of the Company. Such reductions shall take effect as of the date on
which a record is taken for the purpose of such dividend, or, if a record is not
taken, the date as of which the holders of Common Stock of record entitled to
such dividend are to be determined.


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         (c) If any capital reorganization or reclassification of the Common
Stock of the Company, or consolidation or merger of the Company with another
corporation, or the sale of all or substantially all of its assets to another
corporation shall be effected, then, as a condition of such reorganization,
reclassification, consolidation, merger sale, lawful and adequate provision
shall be made whereby the holder hereof shall thereafter have the right to
purchase and receive upon the basis and upon the terms and conditions specified
in this Warrant and in lieu of the shares of the Common Stock of the Company
immediately theretofore purchasable and receivable upon the exercise of the
rights represented hereby, such shares of stock, securities or assets as may be
issued or payable with respect to or in exchange for a number of outstanding
shares of such Common Stock equal to the number of shares of such Common Stock
immediately theretofore purchasable and receivable upon the exercise of the
rights represented hereby had such reorganization, reclassification,
consolidation, merger or sale not taken place, and in any such case appropriate
provision shall be made with respect to the rights and interests of the holder
of this Warrant to the end that the provisions hereof (including without
limitation provisions for adjustment of the Exercise Price per share and of the
number of shares of Common Stock purchasable upon the exercise of this Warrant)
shall thereafter be applicable, as nearly as may be in relation to any shares of
stock, securities or assets thereafter deliverable upon the exercise hereof. The
Company shall not effect any such consolidation, merger or sale, unless prior to
or simultaneously with the consummation thereof the successor corporation (if
other than the Company) resulting from such consolidation or merger or the
corporation purchasing such assets shall assume by written instrument executed
and mailed or delivered to the holder hereof at the last address of such holder
appearing on the books of the Company, the obligation to deliver to such holder
such shares of stock, securities or assets as, in accordance with the foregoing
provisions, such holder may be entitled to purchase. Any such shares of stock,
securities or assets which the holder hereof may be entitled to purchase
pursuant to this paragraph (c) shall be included within the term "COMMON STOCK"
as used herein.

         (d) Upon any adjustment of the number of shares of Common Stock which
may be purchased upon the exercise of the rights represented hereby and/or of
the Exercise Price per share, then and in each such case the Company shall give
written notice thereof, by first class mail, postage prepaid, addressed to the
holder of this Warrant at the address of such holder as shown on the books of
the Company, which notice shall state the Exercise Price per share resulting
from such adjustment and the increase or decrease, if any, in the number of
shares purchasable at such price upon the exercise of this Warrant, setting
forth in reasonable detail the method of calculation and the facts upon which
such calculation is based.

         (e)  In case at any time:

            (i) the Company shall pay any dividend payable in stock upon its
            Common Stock or make any distribution (other than regular cash
            dividends paid at an established annual rate) to the holders of its
            Common Stock;

            (ii) the Company shall offer for subscription pro rata to the
            holders of its common stock any additional shares of stock of any
            class or other rights;


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      (iii) there shall be any capital reorganization or reclassification of the
      Common Stock of the Company, or consolidation or merger of the Company
      with, or sale of all or substantially all of its assets to, another
      corporation; or

      (iv) there shall be a voluntary or involuntary dissolution, liquidation or
      winding up of the Company;

then, in any one or more of such cases, the Company shall give to the holders of
this warrant:

      (aa) at least twenty days' prior written notice of the date on which the
      books of the Company shall close or a record shall be taken for such
      dividend, distribution or subscription rights or for determining rights to
      vote in respect of any such reorganization, reclassification,
      consolidation, merger, sale, dissolution, liquidation or winding up; and,
      in the case of any such dividend, distribution or subscription rights such
      notice shall also specify the date on which the holders of Common Stock
      shall be entitled thereto; and

      (bb) in the case of any such reorganization, reclassification,
      consolidation, merger, sale, dissolution, liquidation or winding up, at
      least twenty days' prior written notice of the date when the same shall
      take place, and said notice shall also specify the date on which the
      holders of Common Stock shall be entitled to exchange their Common Stock
      for securities or other property deliverable upon such reorganization,
      reclassification, consolidation, merger, sale, dissolution, liquidation or
      winding up, as the case may be; and,

      (cc) each such written notice shall be given by first class mail, postage
      prepaid, addressed to the holder of this Warrant at the address of such
      holder as shown on the books of the Company.

4. This Warrant shall be transferable only on the books of the Company by the
holder hereof in person, or by duly authorized attorney on surrender of this
Warrant properly assigned.

5. The holder represents that this Warrant is being acquired with no present
intention of selling or distributing any Common Stock received upon the exercise
hereof, unless registered under Federal and applicable state laws or pursuant to
an exemption from such registration.

6. Neither this Warrant, nor the shares of Common Stock issuable hereunder, have
been registered under the Securities Act of 1933, as amended (the "SECURITIES
ACT"), or the laws of any other jurisdiction, and neither this Warrant nor the
Warrant shares may be offered, sold, transferred, pledged, hypothecated or
otherwise disposed of unless so registered, or unless an exemption from
registration is available pursuant to law.


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<PAGE>   7
      The sale, assignment or other disposition of this Warrant and the shares
of Common Stock issuable hereunder are further restricted by Rule 144,
promulgated by the Securities and Exchange Commission.

      The certificate or certificates representing the Common Stock issued upon
the exercise of this Warrant will bear and be subject to a legend in
substantially the following form:

        "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
   UNDER THE SECURITIES ACT OF 1933 (THE "ACT") OR UNDER THE SECURITIES LAWS OF
   ANY STATE AND MAY BE OFFERED AND SOLD ONLY IF REGISTERED PURSUANT TO THE
   PROVISIONS OF THE ACT AND APPLICABLE STATE SECURITIES LAWS OR AVAILABLE
   EXEMPTION FROM SUCH REGISTRATION."

7. The corporation laws of the State of Delaware shall govern all issues
concerning the relative rights of the Company and its stockholders. All other
questions concerning the construction, validity, enforcement and interpretation
of this Warrant shall be governed by the internal law of the State of New York,
without giving effect to any choice of law or conflict of law provision or rule
(whether of the State of New York or any other jurisdictions) that would cause
the application of the laws of any jurisdictions other than the State of New
York.

8. This Warrant shall be deemed an original even in the event it shall be a
carbon copy or shall be mechanically reproduced, so long as it bears the
original signatures of the designated corporate officers.

9. This Warrant may be assigned at any time, in whole or in part, to an
affiliate of the holder hereof without the consent of the Company. Assuming the
conditions of Section 6 above regarding registration or exemption have been
satisfied, the holder may sell, transfer, assign, pledge or otherwise dispose of
this Warrant, in whole or in part. The holder shall deliver a written notice to
the Company, substantially in the form of the Assignment attached hereto as
Exhibit B, indicating the person or persons to whom the Warrant shall be
assigned and the respective number of warrants to be assigned to each assignee.
The Company shall effect the assignment within ten (10) days, and shall deliver
to the assignee(s) designated by the holder a Warrant or Warrants of like tenor
and terms for the appropriate number of shares.


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10. Any notice or other communication required or permitted to be given
hereunder shall be in writing and shall be effective (a) upon hand delivery or
delivery by facsimile at the address or number designated below (if delivered on
a business day during normal business hours where such notice is to be
received), or the first business following such delivery (if delivered other
than on a business day during normal business hours where such notice is to be
received) or (b) on the second business day following the date of mailing by
express courier service, fully prepaid, addressed to such address, or upon
actual receipt of such mailing, whichever shall first occur. The addresses for
such communications shall be:

         to the Company:            Zila, Inc.
                                    5227 North 7th Street
                                    Phoenix, AZ 85014-2800
                                    Attention:  Mr. Joseph Hines
                                    Facsimile No.: 602/234-2264

      to the Investor at the address or facsimile number set forth below on the
      signature page hereto.

Either party hereto may from time to time change its address or facsimile number
for notices under this Section 10 by giving prior written notice of such change
in the manner provided for giving notice as set forth herein.

11. This Warrant and any term hereof may be changed, waived, discharged or
terminated only by an instrument in writing signed by the party against which
enforcement of such change, waiver, discharge or termination is sought. The
invalidity or unenforceability of any provision hereof shall in no way affect
the validity or enforceability of any other provision.

12. The holder shall deliver to the Company, along with the original Warrant,
the "Form of Warrant Exercise" in order to exercise the Warrant, attached hereto
as Exhibit A.

      IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officers as of the 17th day of October, 1997, the original
issue date.

                                    ZILA, INC.


                                    /s/ Joseph Hines
                                    ------------------------
                                    Joseph Hines
                                    President
ATTEST:


/s/ Janice L. Backus
-----------------------------
Janice L. Backus
Corporate Secretary


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<PAGE>   9
EXHIBIT A

                            FORM OF WARRANT EXERCISE


I/we hereby exercise Zila, Inc. Common Stock Purchase Warrant #_________________

(a)   Number of shares of Zila common stock
      covered in Purchase Warrant #___________                #_________________

(b)   Total Exercise price ($______ per share)                #_________________



__________________________________              ________________________________
Signature                                       Social Security No.

_______________________________________________
Name (please print)

________________________________________________________________
Address
________________________________________________________________


_____________________________________________
Telephone Number

I wish to register my shares of Zila Common stock as follows:

      a.  (  )  Individual Ownership
      b.  (  )  Husband and Wife as Community Property
      c.  (  )  Joint Tenants w/Right to Survivorship (JTROS)
      d.  (  )  Tenants in Common
      e.  (  )  Other _______________________________________________

Dated: ________________________________19_______.


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EXHIBIT B


                               FORM OF ASSIGNMENT


      (To be executed by the registered Warrant Holder desiring to transfer the
Warrant)


      FOR VALUED RECEIVED, the undersigned holder of the attached Warrant hereby
sells, assigns and transfers unto the persons below named the right to purchase
________________ shares of the Common Stock of Zila, Inc. evidenced by the
attached Warrant and does hereby irrevocably constitute and appoints Zila's
Corporate Secretary to transfer the said Warrant on the books of the Company,
with full power of substitution in the premises.

Dated: __________________________ 19 ____


_________________________________________
Signature

Fill in for new Registration of Warrant:

_________________________________________
Name

_________________________________________
Address
_________________________________________


_________________________________________
Please print name and address of assignee
(including zip code number)

NOTICE: The signature to the foregoing Assignment must correspond to the name as
written upon the face of the attached Warrant in every particular, without
alteration or enlargement or any change whatsoever.


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