Generally, thyroid medicines are safe to take with medicines that treat high cholesterol. Statins are the most common cholesterol medicine. One statin, lovastatin, may have an effect on thyroid hormones. It is still safe to use.
The thyroid medicine levothyroxine may not work as well if you are taking a bile acid sequestrant. This is a less common type of cholesterol medicine. If you need to take both these drugs, take them at least 4 hours apart.
Before starting a new medicine, talk to your doctor about all the medicines you are taking. Your doctor may review any symptoms you are having before you take a statin with your thyroid medicine. This makes it easier to know if new symptoms are due to the statins or to your thyroid problem.