What should i do?

This morning my friend took diet pills, caffeine pills and diuretics. She admitted this to me and said that she has been taking this combination for the past few weeks.

my friend is 26 and has suffered from eating disorders in the past.

What should I do? Should I tell her partner what is going on? How do I approach this?

Any advice greatly received

Reply to- "what should i do?"

My sister has has some problems with eating disorders in the past, not the same as your friend but eating disorders no less.
All i can say is to try speaking to your friend about it. Your friend could listen and think about what you are saying or could react totally mad about you talking to her about her own well being. It is a hard subject so i guess sometimes no matter what you say to people, no matter the subject at times; they could take offence and get angry with your help.
If she wants help try and encourage her to see a doctor or speak to her partner first. If she does stop she will need all the support possible.
If you do speak to her partner before confronting her first, make sure she does not feel pressured as this could make her more certain to carry on.

I no it is a horrible subject but is there any signs of your friend self harming? We had this problem with my sister and was very easy for her to hide it at times. Im not saying your friend is, its just best to be aware as im sure you are.

I hope this has been of some help to you and hopefully your friend.
Good Luck!