When should Eltroxin be taken during the day?

Q: My wife is 32 years old and suffering from hypothyroidism for the last 6 years. This started immediately after the birth of our son. She is presently on Eltroxin 150 mcg daily. What is the best time to take Eltroxin; is it with meal or on an empty stomach? Whenever she goes for a lab test of TSH early in the morning on an empty stomach, should she take the medicine and then go for giving the blood sample; or she should not take the medicine on that particular day? We are also planning for our second child, is it advisable considering her hypothyroid status? What precautions should we take?

A:Eltroxin is the brand name of a medicine called thyroxine.It should be taken on empty stomach early in the morning before breakfast (about an hour) since food decreases its absorption.During blood tests, the medicine should be taken as usual because the interest is to assess thyroid function while on medicine.Its use during pregnancy is quite safe. However the dose needs to be increased by about 25 to 40 percent and sometimes even by 50 per cent.There is no problem in becoming pregnant provided euthyroid state is achieved before conception and during early pregnancy as maternal hypothyroidism may adversely affect the neural development in the foetus. Thyroid function should be assessed once pregnancy is confirmed and then again at the beginning of 2nd and 3rd trimesters.