Doc has started palliative chemotherapy for maintenance.

Gefitnat is Gefitinib/Iressa - Not too many studies on effectiveness on OC. My dad was also on this but 500 mg daily. The side-effects may include nausea, vomiting, anorexia, dehydration, skin reactions/scaling of skin, diarrhea etc.

Methotrexate or MTX - is again chemotherapeutic agent, historically most frequent drug used which kills cells by masquerading as folic acid and turning off DNA and RNA synthesis necessary for life. Side-effects may be Loss of appetite, Sores in mouth and on lips, Diarrhea, blood in urine/stool/vomit,headache, fever (due to immuno-suppression). 2.5 mg is kind of low dose. Infact the combination is relatively new for me to comprehend.

Calcium Leucovorin is given as MTX Leucovorin Rescue to prevent good cell damage especially white matter, sheaths, bone marrow and gastrointestinal mucosa cells.

Remember to follow the dosage, review with doc. You need to take good care of your father, please keep in mind that the treatment is not curative in intent. Unfortunately, in India, we do not have enough clinical trials so it is almost end of line unless you decide to go for second opinion abroad.