<PAGE>
Prospectus Supplement No. 1 Filed Pursuant to Rule 424(b)(3)
(To Prospectus dated September 25, 1998) SEC File No. 333-57501
$111,095,000
ALPHARMA INC.
5 3/4% CONVERTIBLE SUBORDINATED NOTES DUE 2005
All capitalized terms used but not defined herein shall have the meanings
ascribed to them in the Prospectus, dated September 25, 1998, forming a part of
the Registration Statement on Form S-3 (Registration No. 333-57501). Any cross
references in this Prospectus Supplement refer to portions of the Prospectus.
The purpose of this Prospectus Supplement is to amend and supplement the
information set forth in the Prospectus regarding the Selling Securityholders.
The following table sets forth the names of additional Selling Securityholders
and (i) the amount of Notes owned by each Selling Securityholder listed below as
of December 30, 1998; (ii) the maximum amount of Notes which may be offered by
each Selling Securityholder listed below under this Prospectus; (iii) the number
of shares of Common Stock owned by each Selling Securityholder listed below as
of December 30, 1998; and (iv) the maximum number of shares of Common Stock
which may be offered by each Selling Securityholder listed below under this
Prospectus. Each of the Selling Securityholders named below acquired Notes in
the amounts reflected in the table below from a Selling Securityholder named in
the Prospectus. All information with respect to beneficial ownership has been
furnished to the Company by the respective Selling Securityholders. Beneficial
ownership of the Notes and Common Stock listed in the table has been determined
in accordance with the applicable rules and regulations promulgated under the
Exchange Act.
<TABLE>
<CAPTION>
AGGREGATE PRINCIPAL AMOUNT NO. OF NO. OF SHARES
PRINCIPAL % OF OF NOTES OFFERED SHARES OFFERED HEREBY
NAME OF SELLING SECURITYHOLDER AMOUNT OF NOTES CLASS HEREBY (1)(2) (1)(2)
- ---------------------------------------- --------------- ----- --------------- ------ --------------
<S> <C> <C> <C> <C> <C>
Health Alliance of Pennsylvania $ 250,000 0.20% $ 250,000 8,743 8,743
Helm Foundation 100,000 0.08% 100,000 3,497 3,497
William G. McGowan Charitable Fund, Inc. 150,000 0.12% 150,000 5,246 5,246
Sue Ling Gin McGowan 50,000 0.04% 50,000 1,749 1,749
The Mitchell Kapor Foundation 50,000 0.04% 50,000 1,749 1,749
The Stepping Stones Foundation 100,000 0.08% 100,000 3,497 3,497
U/W Olt - Taxable Income 250,000 0.20% 250,000 8,743 8,743
Ross Kapor Foundation 50,000 0.04% 50,000 1,749 1,749
ASPCA Pension Fund 100,000 0.08% 100,000 3,497 3,497
LLT Limited 170,000 0.14% 170,000 5,945 5,945
Forest Alternative Strategies Fund A-5 1,850,000 1.48% 1,850,000 64,699 64,699
Forest Alternative Global Strategies A5m 96,000 0.08% 96,000 3,357 3,357
Forest Alternative Strategies Fund A5I 228,000 0.18% 228,000 7,974 7,974
Forest Global Convertible Fund A5 1,656,000 1.32% 1,656,000 57,915 57,915
Fiserv Correspondent Services Inc. 200,000 0.16% 200,000 6,995 6,995
Infinity Investors Limited 1,000,000 0.80% 1,000,000 34,973 34,973
--------------- ----- --------------- ------- --------------
Total $6,300,000 5.04% $6,300,000 220,328 220,328
=============== ===== =============== ======= ==============
</TABLE>
_______________________
(1) All share amounts set forth represents less than 1% of the outstanding Class
A Common Stock.
(2) Reflects the shares of Common Stock into which the Notes held by such
Selling Securityholder are convertible at the initial conversion rate. The
Conversion Price and the number of shares of Common Stock issuable upon
conversion of the Notes are subject to adjustment under certain
circumstances. Assumes conversion into Class A Common Stock of the full
amount of Notes held by the Selling Securityholder at the initial conversion
rate and the offering of such shares by such Selling Securityholder pursuant
to this Prospectus. See "Description of Notes--Conversion Rights."
<PAGE>
Because the Selling Securityholders may, pursuant to this Prospectus, offer
all or some portion of the Notes they presently hold or, with respect to the
Common Stock, have the right to acquire upon conversion of such Notes, no
estimate can be given as to the amount of the Notes and Common Stock that will
be held by the Selling Securityholders upon termination of any such sales. In
addition, the Selling Securityholders identified above and in the Prospectus may
have sold, transferred or otherwise disposed of all or a portion of their Notes
and Common Stock since the date on which they provided the information regarding
their Notes and Common Stock, in transactions exempt from the registration
requirements of the Securities Act. See "Plan of Distribution." Such sales
would affect the data in the table above.
The Company may from time to time, in accordance with the Registration Rights
Agreement, supplement or amend the Prospectus to reflect the required
information concerning any transferee, pledgee, donee or successor to the
Selling Securityholders named in the Prospectus.
The date of this Prospectus Supplement is December 30, 1998.
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