Levothroid

What Is Levothroid?

Levothroid (levothyroxine sodium) is a replacement for a hormone that is normally produced by your thyroid gland to regulate the body's energy and metabolism used to treat hypothyroidism (low thyroid hormone). Levothroid is also used to treat or prevent goiter (enlarged thyroid gland), which can be caused by hormone imbalances, radiation treatment, surgery, or cancer.

What Are Side Effects of Levothroid?

Common side effects of Levothroid include:

• hair loss during the first few months of treatment. This side effect is usually temporary as your body adjusts to Levothroid.

Contact your doctor if you experience serious side effects of Levothroid including:

• headache,
• sleep problems (insomnia),
• feeling nervous or irritable,
• fever,
• hot flashes,
• sweating,
• pounding heartbeats or fluttering in your chest,
• changes in your menstrual periods,
• appetite changes, or
• weight changes.

Dosage for Levothroid

For adult hypothyroidism, Levothroid is started at 12.5-125 mcg/day taken orally. Dose may differ with individuals based on age, the presence of cardiovascular disease, tolerance, side effects, and blood levels of thyroid hormone. It may take one to three weeks before effects are seen.

What Drugs, Substances, or Supplements Interact with Levothroid?

Levothroid may interact with calcium carbonate, ferrous sulfate iron supplement, sucralfate, sodium polystyrene sulfonate, antacids that contain aluminum, and cholesterol-lowering drugs. Tell your doctor all medications or supplements you are taking.

Levothroid During Pregnancy or Breastfeeding

Current information shows that Levothroid may be used during pregnancy. Tell your doctor if you are pregnant as your dose may need to be adjusted. This medication passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breastfeeding.

Additional Information

Our Levothroid (levothyroxine sodium) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

 

Levothroid Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• fast or irregular heartbeats;
• chest pain, pain spreading to your jaw or shoulder;
• shortness of breath;
• fever, hot flashes, sweating;
• tremors, or if you feel unusually cold;
• weakness, tiredness, sleep problems (insomnia);
• memory problems, feeling depressed or irritable;
• headache, leg cramps, muscle aches;
• feeling nervous or irritable;
• dryness of your skin or hair, hair loss;
• irregular menstrual periods; or
• vomiting, diarrhea, appetite changes, weight changes.

Certain side effects may be more likely in older adults.

Common side effects may include:

• chest pain, irregular heartbeats;
• shortness of breath;
• headache, leg cramps, muscle pain or weakness;
• tremors, feeling nervous or irritable, trouble sleeping;
• increased appetite;
• feeling hot;
• weight loss;
• changes in your menstrual periods;
• diarrhea; or
• skin rash, partial hair loss.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Levothroid (Levothyroxine Sodium)

 

Levothroid Professional Information

SIDE EFFECTS

Adverse reactions associated with levothyroxine therapy are primarily those of hyperthyroidism due to therapeutic overdosage (see PRECAUTIONS and OVERDOSAGE). They include the following:

General: fatigue, increased appetite, weight loss, heat intolerance, fever, excessive sweating;

Central nervous system: headache, hyperactivity, nervousness, anxiety, irritability, emotional lability, insomnia;

Musculoskeletal: tremors, muscle weakness;

Cardiovascular: palpitations, tachycardia, arrhythmias, increased pulse and blood pressure, heart failure, angina, myocardial infarction, cardiac arrest;

Respiratory: dyspnea;

Gastrointestinal: diarrhea, vomiting, abdominal cramps and elevations in liver function tests;

Dermatologic: hair loss, flushing;

Endocrine: decreased bone mineral density; Reproductive: menstrual irregularities, impaired fertility.

Pseudotumor cerebri and slipped capital femoral epiphysis have been reported in children receiving levothyroxine therapy. Overtreatment may result in craniosynostosis in infants and premature closure of the epiphyses in children with resultant compromised adult height.

Seizures have been reported rarely with the institution of levothyroxine therapy.

Inadequate levothyroxine dosage will produce or fail to ameliorate the signs and symptoms of hypothyroidism.

Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products. These include urticaria, pruritus, skin rash, flushing, angioedema, various GI symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness and wheezing. Hypersensitivity to levothyroxine itself is not known to occur.

Read the entire FDA prescribing information for Levothroid (Levothyroxine Sodium)