Tenn. Code Ann. § 33-6-1003: Duration of declaration - Expiration - Revocation

(a) A declaration for mental health treatment continues in effect for two (2) years, for a lesser period if so stated, or until revoked, whichever is sooner. If a declaration for mental health treatment has been invoked and is in effect at the expiration date, the declaration remains effective until the service recipient is capable of making mental health treatment decisions but no more than thirty (30) days after the expiration date. Subsequent declarations shall conform to all requirements of § 33-6-1004 .

(b) A service recipient may revoke a declaration in whole or in part at any time orally or in writing if the service recipient is capable of making mental health treatment decisions. Making a new declaration revokes an earlier declaration. It is presumed that a service recipient is capable of making mental health treatment decisions. The presumption is a presumption affecting the burden of proof.

(c) A revocation is effective when a service recipient communicates the revocation to the attending physician or other provider. The attending physician or other provider shall note the revocation as part of the service recipient's medical record.