How long has it been like this? Could she have stepped on a bee? did you feel for a stinger or splinter?
Nice warm soaks in Epsom salt water may help[ with swelling.
Just don't let her drink the water.
Here is a med chart that gives dose and how often
https://sites.google.com/a/poultrypedia.com/poultrypedia/medicine-chart
good idea to soak in Epsom salt water it can help with swelling.
I have a Muscovy drake who is 11yrs old and most likely has arthritis in his leg I
give him 81mg. he is 15lb.
Just make sure to give it to her when she eats so she has food on her tummy. I wrap it in a tiny piece of bread and my boy gobbles it right down.