Iowa Code § 228.4
An individual or an individual's legal representative may revoke a prior authorization by providing a written revocation to the recipient named in the authorization and to the mental health professional, data collector, or employee or agent of a mental health professional, of a data collector, or of or for a mental health facility previously authorized to disclose the mental health information. The revocation is effective upon receipt of the written revocation by the person previously authorized to disclose the mental health information. After the effective revocation date, mental health information shall not be disclosed pursuant to the revoked authorization. However, mental health information previously disclosed pursuant to the revoked authorization may be used for the purposes stated in the original written authorization.
Iowa Code § 228.4
86 Acts, ch 1082, §4