Health & Safety Code Section 166.165
(a)A person who is a near relative of the principal or a responsible adult who is directly interested in the principal, including a guardian, social worker, physician, or clergyman, may bring an action to request that the medical power of attorney be revoked because the principal, at the time the medical power of attorney was signed:
(1)was not competent; or
(2)was under duress, fraud, or undue influence.
(a-1)In a county in which there is no statutory probate court, an action under this section shall be brought in the district court. In a county in which there is a statutory probate court, the statutory probate court and the district court have concurrent jurisdiction over an action brought under this section.
(b)The action may be brought in the county of the principal’s residence or the residence of the person bringing the action.
(c)During the pendency of the action, the authority of the agent to make health care decisions continues in effect unless the court orders otherwise.
Section 166.165 — Civil Action,
https://statutes.capitol.texas.gov/Docs/HS/htm/HS.166.htm#166.165 (accessed Dec. 2, 2023).