GUARANTEE

     For value received, SHIRE PHARMACEUTICALS GROUP PLC, a public limited
company organized and existing under the laws of England and Wales (herein
called the "Guarantor", which term includes any successor Person under the
Indenture referred to in the Security upon which this Guarantee is endorsed),
hereby irrevocably and unconditionally guarantees to the Holder of the Security
upon which this Guarantee is endorsed, and to the Trustee on behalf of each such
Holder, the due and punctual payment of the principal of (and premium, if any,
on) and interest, if any, on such Security when and as the same shall become due
and payable, whether at the Stated Maturity, by declaration of acceleration,
call for redemption or otherwise, in accordance with the terms of said Security
and of the Indenture. In case of the failure of the Issuer punctually to make
any such payment of principal (or premium, if any) or interest, if any, the
Guarantor hereby agrees to cause any such payment to be made punctually when and
as the same shall become due and payable, whether at the Stated Maturity, by
declaration of acceleration, call for redemption or otherwise, and as if such
payment were made by the Issuer.

     The Guarantor hereby agrees that it shall make all payments in respect of
principal of (and premium, if any, on) and interest (including interest on
amounts in default), if any, on the Securities or the payment of any other sums
due on the Securities pursuant to this Guarantee without deduction or
withholding for or on account of any present or future taxes, duties,
assessments or governmental charges of whatever nature imposed or levied upon or
as a result of such payments by or on behalf of any taxing authority of the
United Kingdom, unless deduction or withholding of such taxes, duties,
assessments or governmental charges is required by law.

     The Guarantor hereby agrees that its obligations hereunder shall be as if
it were principal debtor and not merely surety, and shall be absolute and
unconditional, irrespective of the validity, regularity or enforceability of
said Security or the Indenture, the absence of any action to enforce the same,
any waiver or consent by the Holder of said Security or by the Trustee or the
Paying Agent with respect to any provisions thereof or of the Indenture, the
recovery of any judgment against the Issuer or any action to enforce the same or
any other circumstances which might otherwise constitute a legal or equitable
discharge or defense of a guarantor. The Guarantor hereby waives diligence,
presentment, demand of payment, filing of claims with a court in the event of
insolvency or bankruptcy of the Issuer, any right to require a proceeding first
against the Issuer, protest or notice with respect to said Security or the
indebtedness evidenced thereby and all demands whatsoever, and covenants that
this Guarantee will not be discharged except by complete performance of its
obligations contained in the Indenture, said Security and this Guarantee.

     The Holder of the Security on which this Guarantee is endorsed is entitled
to the further benefits relating thereto set forth in the Security and the
Indenture. No reference herein to the Indenture and no provision of this
Guarantee, said Security or the Indenture shall alter or impair the guarantee of
the Guarantor, which is absolute and unconditional, of the due and punctual
payment of the principal of (and premium, if any, on) and interest, if any, the
Security upon which this Guarantee is endorsed.



<PAGE>

     The Indenture, the Securities and this Guarantee are governed by and will
be construed in accordance with the laws of the State of New York, without
regard to the applicable principles of conflicts of laws to the extent that the
application of the laws of another jurisdiction would be required thereby.

     REFERENCE IS HEREBY MADE TO THE FURTHER PROVISIONS OF THIS GUARANTEE SET
FORTH IN SAID SECURITY AND IN THE INDENTURE, WHICH FURTHER PROVISIONS SHALL FOR
ALL PURPOSES HAVE THE SAME EFFECT AS IF SET FORTH AT THIS PLACE.

     Terms used in this Guarantee and not defined herein shall have the meaning
assigned to them in the Indenture.

     This Guarantee shall not be valid or obligatory for any purpose until the
certificate of authentication on the within Security has been executed by the
Trustee, directly or through an Authenticating Agent, by manual or facsimile
signature of an authorized signatory.


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<PAGE>


     IN WITNESS WHEREOF, the Guarantor has caused this Guarantee to be duly
executed.


Dated:


[CORPORATE SEAL]                    SHIRE PHARMACEUTICALS GROUP PLC


                                     By:
                                        ----------------------------------------
                                          Name:
                                          Title:


                                     Attest:
                                            ------------------------------------
                                             Name:
                                             Title:







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