How do you get a court supena for medical intervention in CA?

An 18 year old or older individual with anorexia poses a severe health risk to herself. The law allows adults to make their own desicions concerning health, however, it is clear that anorexia is a psychiatric illness, therefore one could make the allegation that the individual refusing medical istance is not in her mind. How can one get a court supena or the type of doent that will allow medical personnel to go into the individual's property and take her into the hospital against her wishes? If you don't need a court supena, what other legal doent will allow this in the state of CA?