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                                   EXHIBIT 5.1


                   [COOLEY  GODWARD LETTERHEAD]

October 8, 1997



Inhale Therapeutic Systems
1525 Industrial Way
Belmont, California 94002

Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection 
with the filing by Inhale Therapeutic Systems (the "Company") of a 
Registration Statement on Form S-3, number 333-37195 (the "Registration 
Statement") with the Securities and Exchange Commission covering the offering 
of up to one million seven hundred twenty-five thousand (1,725,000) shares of 
the Company's Common Stock, no par value (the "Shares").

In connection with this opinion, we have examined the Registration Statement and
related Prospectus, your Restated Articles of Incorporation and Bylaws, as
amended, and such other documents, records, certificates, memoranda and other
instruments as we deem necessary as a basis for this opinion.  We have assumed
the genuineness and authenticity of all documents submitted to us as originals,
the conformity to originals of all documents submitted to us as copies thereof,
and the due execution and delivery of all documents where due execution and
delivery are a prerequisite to the effectiveness thereof.

On the basis of the foregoing, and in reliance thereon, we are of the opinion
that the Shares, when sold and issued in accordance with the Registration
Statement and related Prospectus, will be validly issued, fully paid, and
nonassessable.

We consent to the filing of this opinion as an exhibit to the Registration
Statement.

Very truly yours,


COOLEY GODWARD LLP



/s/ Mark P. Tanoury
Mark P. Tanoury
