There are many cysts in the abdomen.
You did not mention the full name of the cyst and the exact location of it in the abdomen.
If the cyst is still present after drainage
of pus,then it has to be removed.
No role of medicines in this case.
You can go for Laparoscopic method(keyhole).
If she is not having complaint of pain abdomen in that area,it can be postponed till symptoms appear.
So,decide as per her symptoms.
Wish her good health