Can I split Losartan pills to finish the higher dose. Split 50 MG to25 MG?

Try to stay on topic. Whether or not the doctor wants it is irrelevant to the question. And actually they CAN be cut. For anybody else with half a brain, the active ingredient may not be equally distributed so if you cut a 100mg you may get 35mg on one half and 65 on the other which will even out in your blood plasma over time.
To kaismama- please stop. Really. You are not the pill cutting police. And your info is wrong.

Actually extended release losartan is very dangerous to split. I had 3 incidents in the past 6 months of syncope. After 2 MRIs, several EEGs and a suspended drivers license (suspected epilepsy) my PCP asked me to bring in my medications. By luck he opened the losartan and saw 3 half 100mg pills in the bottle and asked me how the got broken. I told him 3 times I took a half dose on days I missed the dose. That's when I learned that breaking an extended release pill makes the dissolve faster and causes a rapid drop in blood pressure. Which led to my syncope and serious injury to my head and face. Not to mention being labeled an epileptic, which was reversed.

According to my pharmacist, only the scored tablets can be split. The extended release tablets should not be split.