I have been on Tarceva for 13 months, have had the rash and dry mouth. A mouth wash with out alcohol is the best. Also I found it best to take the Tarceva in the evening after my meal.
You must wait 2 hours, empty stomach, the pill can make you tired. Also, diarrhea is a side effect that I have, and I take Lomotil, 2 pills three times a day. It really works, take them right before you eat.
I am a female, non-smoker, had non-small cell and squamous cell both in the same lobe of the lung!
Best of luck, you MUST keep a positive attitude.
Let us know how your mother does. She is in my prayers
Vette