There is no warning or instruction about lying down after you take levothyroxine in the drug’s detailed prescribing information. Unless your doctor gives you different directions, you can lie down after taking it.

The prescribing information for levothyroxine advises you to take one pill daily on an empty stomach 30 minutes to 1 hour before breakfast.

Levothyroxine is an oral medication used to treat hypothyroidism. Your doctor will determine the dose of levothyroxine based on your age and your weight. The dose may be adjusted based on blood testing of your thyroid hormone levels.

• You should swallow the tablet or capsule whole. Do not chew or crush the tablet or capsule.
• Take the medication with a full glass of water.
• Some medications may interfere with levothyroxine, so tell your doctor about all of the medications you take, including over-the-counter medications and any supplements. Certain medications may slow down its absorption, and you should take these medicines at least 4 hours before taking levothyroxine.
• Some foods may also affect levothyroxine. Ask your doctor about consuming walnuts, fiber supplements, soybeans and grapefruit juice.

If you miss a dose, you should take it as soon as you remember, unless it is almost time for the next daily dose—then you should just take the next dose. Never double the dose to make up for a missed dose from the day before.