Medication Guide — Levothyroxine Sodium

Patient-friendly FDA guidance and safety information.

Last updated · May 13, 2026Source: DailyMed ↗

Boxed Warning

Thyroid hormones, including Levothyroxine Sodium Tablets, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss.

In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction.

Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.

WARNING: NOT FOR TREATMENT OF OBESITY OR FOR WEIGHT LOSS

See full prescribing information for complete boxed warning

Thyroid hormones, including Levothyroxine Sodium Tablets should not be used for the treatment of obesity or for weight loss.
Doses beyond the range of daily hormonal requirements may produce serious or even life threatening manifestations of toxicity (6, 10).

Poison Help

If you suspect an overdose or accidental ingestion, call Poison Control: 1-800-222-1222 (free, 24/7, U.S.). For life-threatening symptoms, call 911.

Dosing and Administration

•Instruct patients to take Levothyroxine Sodium Tablets only as directed by their healthcare provider.
•Instruct patients to take Levothyroxine Sodium Tablets as a single dose, preferably on an empty stomach, one-half to one hour before breakfast.
•Inform patients that agents such as iron and calcium supplements and antacids can decrease the absorption of levothyroxine. Instruct patients not to take Levothyroxine Sodium Tablets within 4 hours of these agents.
•Instruct patients to notify their healthcare provider if they are pregnant or breastfeeding or are thinking of becoming pregnant while taking Levothyroxine Sodium Tablets.

Sources

RxCUI: 966222

NDC: 71205-353

Last fetched: May 13, 2026

Source: DailyMed ↗

⚠️ Disclaimer

This information is for educational purposes only and is not medical advice. Always consult your doctor, pharmacist, or other licensed healthcare professional before starting, stopping, or changing any medicine. Read full medical disclaimer.