My wife has been on Tarceva since September 2011. Lately she is suffering from all kinds of neurological side effects of visual migraines, Acephaligic migraine and symptoms of Scintillating scotoma. We have gone round and round with radiation oncologist, neurologist and medical oncologist. No body seems to have any answer. MRI's of her brain is showing no signs of detectable cancer. Now they are suspecting that it could be electrolytes imbalance and possibly deficiency in systemic magnesium
In my frantic research I came across a study by the American Society of Nephrologist on "Effect of the EGFR inhibitor Erlotinib on Magnesium Handling" which hinted that prolong use of tarceva might induced systemic deficiency of Magnesium that is not easily detected by serum magnesium test.
It is known that Tarceva will mess up the magnesium reabsorption in the kidney. Is there any study on long term use of tarceva causing hypomagnesemia?