Liquid medications would be handled differently, by the body, since they don't have have to dissolve. I'd say you'd be okay waiting 30 minutes to an hour, but you really should check with your doctor or pharmacist to be sure.
As the other posters noted, consistency is the key.
Standard wait time between hormone med in conjuntion with other meds, supplements, Etc... is 4 hrs.
I take diabetic med with levo same time everyday, reason being I cannot wait 4 hrs to eat, and my diabetic med is taken 30 min before first meal.
Consistency is the key, but any other med, supp I take 4 hrs after levo dose. So far this has worked well for me.
That's a good question. It is unclear whether there would be any serious interaction, however the synthroid works best when the dose is consistent and given at exactly the same time every day. To provide the most consistent doseage it should ideally be taken without other medications. Synthroid dissolves quite readily and an hour between medications should cause no problems. That being said, if the interval is less, there should be no great harm.