Hello, These medications should not be taken all together. If taken together, they can reduce the absorption of Synthroid and thus reduce its efficacy. To ensure adequate absorption Synthroid is best taken in the morning, with water, on an empty stomach, at least half an hour before eating and drinking anything. Since other prescribed medications can decrease the absorption of Synthroid, they need to be taken at least four hours apart from Synthroid. Since you have to start taking lisinopril, it is advised to be taken in the evening with a meal to reduce side-effects. As the starting dose of lisinopril can lower the blood-pressure significantly (postural hypotension). You need to be careful when getting out of bed or off the couch. You should get up slowly to avoid dizziness. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Mohammed Taher Ali