Thank you for posting your question here, I will try to answer it to the best of my abilities.
In most cases the patient starts getting better between the 4-7th day, as such I would recommend she continues taking the medication till the seventh day. What you should understand is that, chicken pox
in adults can be serious and life threatening, so it never hurts to be cautious. Also make sure your wife doesnt take any aspirin
during this phase.
I hope this answered your question.