When my 81-year-old mother is in one of her manic states, she blows all of her money and maxes out her cards. Legally, what can I do to prevent this?

Some of it could be avoided by utilizing a representative payee servivce outside of the family.

Even with a POA your mom if not declaired incompitant, can do anything she wants with her money. That is what I was told. Now my cousin has "taken: my mom and they have decided to "NOT" pay any of her bills associated with her "other life" these include her home owners dues, medical insurance and home owners insurance. When speeking to an attoinie I was told my mom is allowed to make all the mistakes she wants. Even catastrophic ones. So my advice is buckle up it's gonna be a bumpy road. Watch out that a family member dose not see you as the bad guy and step in and take over. If posssible try to convince your mom to get a financial advisor to control her money...good luck mine would not even talk about that...now her entire lifes work is going to get taken because she is making "bad choices". And all I can do is watch. Oh yea a POA can be thrown out at anytime by your parent, and all the work you do can be lost.

Do you have power of attorney? If so, perhaps you could freeze her credit. If not, I don't think you can do anything.
My own mother runs up her credit cards with QVC shopping. Would love to hear advice.