A few things I've learnt off the internet about taking thyroid medication that my Doctor didn't tell me.
1. Take at the same time of day
2. Take an hour before food or drink (apart from water) OR at least 2 hours after eating.
3. If you're taking a calcium supplement (I am) - leave at least 4 hours after taking your thyroxine, before taking your calcium.
4. Soy is a thyroid depressant, so limit your intake of soy foods.
I don't know why it doesn't state these things on the instructions. I'm not sure if it makes that much difference, but I need to do all I can to make sure that my thyroid levels are as good as can be, so I'm following the above guidelines.