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                                                                    Exhibit 4.1B


                 SECOND AMENDMENT TO AND SUPPLEMENTAL INDENTURE


                  THIS SECOND AMENDMENT TO AND SUPPLEMENTAL INDENTURE ("Second
Amendment") is made this 19th day of March, 1998, by and among Chattem, Inc., a
Tennessee corporation (the "Company"), Signal Investment & Management Co., a
Delaware corporation (the "Guarantor") and SouthTrust Bank, National
Association, a national banking association (the "Trustee"), under the
following circumstances:

                  A. The Company has issued its Series B Senior Subordinated
Notes due 2004 in the original aggregate principal amount of $75,000,000
(herein the "Notes").

                  B. The Notes are secured by the Indenture dated August 3,
1994 among the Company, the Guarantor and the Trustee ("Indenture").

                  C. The Company and the Guarantor, having received the written
approval of the holders of at least a majority in interest in principal amount
of the Notes pursuant to Section 9.02 of the Indenture, and the Trustee desire
to amend the Indenture as provided hereinafter.

                  NOW, THEREFORE, in consideration of the premises and of the
mutual covenants and agreements contained in this Second Amendment, the parties
agree:

                  1. The second paragraph of Section 4.09 of the Indenture
shall be deleted in its entirety and in lieu thereof shall be inserted the
following:

                           The foregoing limitations will not apply to (a) the
                  incurrence by the Company of Indebtedness under the New Credit
                  Agreement of up to $50 million in aggregate principal amount
                  at any time outstanding, (b) Indebtedness outstanding on the
                  Issuance Date, (c) the incurrence by the Company of
                  Indebtedness represented by the Securities, (d) the incurrence
                  by the Company of Indebtedness issued in exchange for, or the
                  proceeds of which are used to extend, refinance, renew,
                  replace or refund Indebtedness referred to in clauses (b) or

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                  (c) above (the "Refinancing Indebtedness"); PROVIDED, HOWEVER,
                  that unless the proceeds of such Refinancing Indebtedness will
                  be used to retire all outstanding Securities (1) the principal
                  amount of such Refinancing Indebtedness shall not exceed the
                  principal amount of the Indebtedness so extended, refinanced,
                  renewed, replaced, substituted or refunded (plus the amount of
                  premiums and expenses incurred in connection therewith); (2)
                  the Refinancing Indebtedness shall have a Weighted Average
                  Life to Maturity equal to or greater than the remaining
                  Weighted Average Life to Maturity of (x) the Securities or (y)
                  the Indebtedness being extended, refinanced, renewed, replaced
                  or refunded, whichever has the shorter Weighted Average Life
                  to Maturity; and (3) if applicable, the Refinancing
                  Indebtedness shall be subordinated in right of payment to the
                  Securities on terms at least as favorable to the Holders of
                  Securities as those contained in the documentation governing
                  the Indebtedness being extended, refinanced, renewed, replaced
                  or refunded, (e) intercompany Indebtedness between or among
                  the Company and any of its Wholly Owned Subsidiaries that are
                  Guarantors, (f) Hedging Obligations that are incurred in order
                  to fix or hedge interest rate risk with respect to floating
                  rate Indebtedness that is permitted by the terms of this
                  Indenture, or (g) the guarantee by the Company or any of the
                  Guarantors of Indebtedness of the Company or any Guarantor
                  that is permitted to be incurred by another provision of this
                  covenant.

                  2. The effectiveness of this Second Amendment is conditioned
upon (i) the closing of the Company's acquisition of the BAN line of
anti-perspirant/deodorant products from Bristol-Myers Squibb Company pursuant to
an agreement dated February 22, 1998, and (ii) at the time the condition in this
Section 2(i) is satisfied, the absence of any existing or proposed law or
regulation which would, and the absence of any injunction or action or other
proceeding (pending or threatened) which (in the


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case of any action or proceeding, if adversely determined) would, make unlawful
or invalid or enjoin or delay the implementation of this Second Amendment, the
entering into of this Second Amendment or the payment of any consent fee or
question the legality or validity of any thereof. Each of the foregoing
conditions to the effectiveness of this Second Amendment is for the sole
benefit of the Company and may be waived by the Company at any time.

                  3. Except as expressly set forth herein, this Second
Amendment shall not supersede or otherwise modify the terms and conditions of
the Indenture.




























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                  IN WITNESS WHEREOF, this Second Amendment to and Supplemental
Indenture has been executed by a duly authorized officer of the Company, the
Guarantor and the Trustee.


Dated as of March 19, 1998.

ATTEST:                                           CHATTEM, INC.


By:                                               By:
   ---------------------------                    ---------------------------
   Secretary                                      A. Alexander Taylor, II
                                                  President
[CORPORATE SEAL]


Dated as of March 19, 1998.

ATTEST:                                           SIGNAL INVESTMENT & MANAGEMENT
                                                  CO., a Guarantor


By:                                               By:
   ---------------------------                    ---------------------------
   Secretary                                      A. Alexander Taylor, II
                                                  President
[CORPORATE SEAL]


Dated as of March 19, 1998.

ATTEST:                                           SOUTHTRUST BANK, NATIONAL
                                                    ASSOCIATION

By:                                               By:
   ---------------------------                    ---------------------------
                                                  Name:
                                                  Title:
[CORPORATE SEAL]






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