Steroid eyedrops is the first line of treatment. Sometimes, we have to inject steroids around the eye. Sometimes, we inject steroids straight into the eye as well. Then there are systemic medications that can be used.
The bigger question is why her iritis is recurring. I am assuming that she has undergone a thorough workup for underlying causes of recurrent iritis (blood tests, Xray, and if indicated biopsy and culture of the fluid in the eye).
Hope this helps and thank you.
If there is an underlying systemic problem, then there are medications such as Imuran, Plaquenil, or Metrotrexate that can also be used. Let me know what she says.