Mo. Rev. Stat. § 630.180: Treatment by religious practice to be permitted.

The provisions of this chapter and chapters 631, 632 and 633 shall not be construed as authorizing any form of compulsory medical treatment of any person who is being treated by prayer in the practice of the religion of any church which teaches reliance on spiritual means for healing unless the person or his legal guardian, if any, consents to such treatment.