Tirosint (Oral)

Levothyroxine is used to treat hypothyroidism, which is when the thyroid gland does not make enough thyroid hormone. Levothyroxine is also used to help reduce the size of enlarged thyroid glands (known as a goiter) and to treat thyroid cancer.

This medicine is available only with your doctor's prescription.

It is very important for your doctor to check how you or your child are doing at regular visits. This will help your doctor see if the medicine is working well and decide if you should keep taking it. Blood tests will be needed to check for unwanted effects.

Levothyroxine should not be used to treat obesity or to lose weight. This medicine is not effective for weight loss. Taking large amounts of levothyroxine can cause serious unwanted effects.

Hypothyroidism can sometimes cause infertility in both men and women. Levothyroxine should not be used to treat infertility unless it is due to hypothyroidism.

For patients with diabetes: It is very important to monitor your blood or urine sugar levels as instructed by your doctor. Contact your doctor right away if you notice any changes in your sugar levels.

If you think you might be pregnant while using this medicine, inform your doctor immediately. You may need a higher dose of levothyroxine during pregnancy.

Women who are post-menopausal or who use this medicine for a long time may experience some bone loss, which could lead to osteoporosis. Discuss any questions or concerns you have with your doctor.

Call your doctor immediately if you or your child experience rapid or irregular heartbeats, chest pain, leg cramps, headaches, nervousness, irritability, trouble sleeping, tremors, changes in appetite, weight gain or loss, vomiting, diarrhea, excessive sweating, heat intolerance, fever, changes in menstrual periods, hives, or a skin rash. These could be signs of too much medicine in your body.

This medicine may cause severe hypothyroidism, known as myxedema coma, which can be life-threatening and requires immediate medical attention. Contact your doctor right away if you have weakness, confusion or are unresponsive, feel cold, have low body temperature, swelling of the body (especially the face, tongue, and lower legs), or difficulty breathing.

Do not stop taking this medicine suddenly without first talking to your doctor. Your doctor may want you or your child to gradually reduce the dosage before stopping completely.

Make sure any doctor or dentist treating you knows that you or your child are using this medicine. You or your child may need to stop using this medicine several days before having surgery or medical tests.

A temporary loss of hair may happen during the first few months of levothyroxine therapy. Ask your doctor if you have any concerns about this.

Do not take other medicines unless your doctor has discussed them with you. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, you and your doctor must consider the risks and benefits of the medicine. For this medicine, here are some important points:

Allergies

Tell your doctor if you have ever had an unusual or allergic reaction to this medicine or any other medicines. Also, inform your healthcare professional about any other allergies you may have, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Studies so far have not shown any specific problems in children that would limit the use of levothyroxine. However, your child's doctor will monitor your child closely for heart issues during the first 2 weeks of treatment.

Geriatric

Studies have not shown specific problems in elderly patients that would limit the use of levothyroxine. However, older adults are more likely to have heart or blood vessel problems related to aging, which may require careful monitoring and possible dose adjustments for those taking levothyroxine.

Breast Feeding

Research in women indicates that this medication poses minimal risk to an infant when used during breastfeeding.

Interactions with Medicines

Some medicines should never be used together. In other cases, two different medicines may be used at the same time, even if there is a risk of interaction. If you are taking this medicine, it is crucial that your healthcare professional knows about any of the medicines listed below. The following interactions are noted for their potential importance and may not include all possible interactions.

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed, your doctor may adjust the dose or frequency of one or both medicines.

• Furosemide
• Iopromide
• Midodrine

Using this medicine with any of the following medicines may increase the risk of certain side effects, but taking both may be the best treatment for you. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both medicines.

• Aluminum Carbonate, Basic
• Aluminum Hydroxide
• Aluminum Phosphate
• Calcium Acetate
• Calcium Carbonate
• Calcium Citrate
• Chlorotrianisene
• Cholestyramine
• Chromium
• Ciprofloxacin
• Colesevelam
• Conjugated Estrogens
• Conjugated Estrogens Synthetic A
• Conjugated Estrogens Synthetic B
• Dexlansoprazole
• Dienestrol
• Diethylstilbestrol
• Dihydroxyaluminum Aminoacetate
• Dihydroxyaluminum Sodium Carbonate
• Esomeprazole
• Esterified Estrogens
• Estradiol
• Estramustine
• Estriol
• Estropipate
• Ethinyl Estradiol
• Fosphenytoin
• Imatinib
• Iron
• Kelp
• Lansoprazole
• Lanthanum Carbonate
• Lopinavir
• Magaldrate
• Magnesium Carbonate
• Magnesium Hydroxide
• Magnesium Oxide
• Magnesium Trisilicate
• Mestranol
• Omeprazole
• Pantoprazole
• Patiromer
• Phenytoin
• Polyestradiol Phosphate
• Promestriene
• Quinestrol
• Rabeprazole
• Rifampin
• Ritonavir
• Semaglutide
• Sevelamer
• Simvastatin
• Tibolone

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around meal times or with specific foods due to possible interactions. Using alcohol or tobacco with some medicines can also lead to interactions. The following interactions are noted for their potential significance and may not include all possible interactions.

Using this medicine with any of the following may increase the risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may modify the dose or frequency of this medicine or provide special instructions regarding food, alcohol, or tobacco.

• Enteral Nutrition
• Soybean

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to inform your doctor if you have any other medical issues, especially:

• Adrenal gland insufficiency (underactive adrenal gland), untreated or
• Heart attack, acute or recent or
• Thyrotoxicosis (overactive thyroid), untreated—This medicine should not be used in patients with these conditions.

• Adrenal gland problems or
• Anemia, pernicious or
• Angina (severe chest pain), history of or
• Blood clotting problems, or history of or
• Diabetes or
• Heart or blood vessel disease (e.g., coronary artery disease, heart failure), history of or
• Heart rhythm problems (e.g., arrhythmia, atrial fibrillation), history of or
• Osteoporosis, history of—Use with caution. This medicine may worsen these conditions.

• Hypoproteinemia (low levels of protein in the blood), severe or
• Kidney disease (e.g., nephrosis) or
• Liver disease (e.g., hepatitis), severe or
• Pituitary gland problems (e.g., acromegaly) or
• Porphyria (enzyme problem)—Use with caution. A dose adjustment of levothyroxine may be necessary for patients with these conditions.

• Patients who have difficulty swallowing capsules (including children younger than 6 years of age)—Tirosint® should not be given to these patients.

Along with its intended effects, a medicine may cause some unwanted effects. Not all of these side effects may happen, but if they do, you may need medical attention.

Check with your doctor right away if any of the following side effects occur:

Less common

• Chest pain, discomfort, or tightness
• decreased urine output
• difficult or labored breathing
• difficulty with swallowing
• dilated neck veins
• extreme fatigue
• fainting
• fast, slow, irregular, pounding, or racing heartbeat or pulse
• fever
• heat intolerance
• hives or welts, skin itching, rash, or redness
• irregular breathing
• irritability
• menstrual changes
• nausea
• pain or discomfort in the arms, jaw, back, or neck
• sweating
• swelling of the eyes, face, lips, throat, or tongue
• tremors

Rare

• Blurred or double vision
• dizziness
• eye pain
• lack or slowing of normal growth in children
• limp or walk favoring one leg
• pain in the hip or knee
• seizures
• severe headache

Get emergency help right away if any of the following symptoms of overdose happen:

Symptoms of overdose

• Change in consciousness
• cold, clammy skin
• confusion
• disorientation
• fast or weak pulse
• lightheadedness
• loss of consciousness
• sudden headache
• sudden loss of coordination
• sudden slurring of speech

Some side effects may happen that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Your health care professional may also be able to suggest ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

• Change in appetite
• crying
• diarrhea
• false or unusual sense of well-being
• fear or nervousness
• feeling not well or unhappy
• feeling of discomfort
• feeling of warmth
• feeling things are not real
• feelings of suspicion and distrust
• hair loss
• headache
• increased appetite
• mental depression
• muscle weakness
• quick to react or overreact emotionally
• rapidly changing moods
• redness of the face, neck, arms, and occasionally, upper chest
• restlessness
• stomach cramps
• trouble getting pregnant
• trouble sitting still
• unusual tiredness or weakness
• vomiting
• weight gain or loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Ermeza
• Levothroid
• Levoxyl
• Synthroid
• Tirosint
• Tirosint-Sol
• Unithroid

Available Dosage Forms:

• Capsule, Liquid Filled
• Solution
• Tablet

Therapeutic Class: Thyroid Supplement

This medicine will need to be taken for the rest of your life or your child's life. Do not stop taking this medicine or change your dose without first checking with your doctor. You may have to take this medicine for 4 to 8 weeks before your symptoms start to get better.

Take this medicine in the morning on an empty stomach, at least 30 to 60 minutes before eating breakfast.

Swallow the capsule whole. Do not cut, chew, or crush it.

If your child is unable to swallow the tablet, you may crush and mix it in 1 to 2 teaspoons (5 to 10 milliliters) of water. Give the mixture right away using a spoon or dropper. Do not mix the tablet with any other liquid except water. Do not store the mixture for future use.

If you are using the oral liquid:

• This medicine may be mixed with water or be given directly into the mouth.
• If mixed with water, squeeze the contents of 1 single unit-dose ampule into a glass or cup containing water. Stir and drink it immediately. Add some water to the glass or cup and drink the water. This will help get all of the medicine out of the glass or cup. Do not mix this medicine with any other liquid except water. Do not store the mixture for later use.
• If taken without water, squeeze the medicine directly into the mouth or into a spoon and swallow it immediately.

If you are using kayexalate, lanthanum, orlistat, sevelamer, sucralfate, antacids (eg, aluminum or magnesium hydroxide, simethicone, Maalox®, Mylanta®, Tums®), medicine to lower cholesterol (eg, cholestyramine, colesevelam, colestipol, Prevalite®,Welchol®, Colestid®), stomach medicine (eg, lansoprazole, omeprazole, pantoprazole, Aciphex®, Dexilant®, Nexium®, Prevacid®, Prilosec®), or any medicine that contains calcium or iron, take them at least 4 hours before or 4 hours after you take levothyroxine.

Cotton seed meal, dietary fiber, soybean flour (infant formula), or walnuts may decrease the absorption of this medicine from your body. You may have to take this medicine at a different time of day from when you eat these foods. Talk with your doctor more about this if you have concerns.

Do not eat grapefruit or drink grapefruit juice while you are using this medicine.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (capsules): For hypothyroidism: Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 1.7 microgram (mcg) per kilogram (kg) of body weight per day but may be less in older adults. Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day. Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day. Children younger than 6 years of age—Use is not recommended as your child might not be able to swallow the capsules. For thyroid cancer: Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually more than 2 microgram (mcg) per kilogram (kg) of body weight per day. Children—Use and dose must be determined by your doctor.
• For oral dosage form (solution): For hypothyroidism: Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 1.7 microgram (mcg) per kilogram (kg) of body weight per day. Your doctor may adjust your dose as needed. Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day. Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day. Children 1 to 5 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 5 to 6 mcg per kg of body weight per day. Children 6 to 12 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 6 to 8 mcg per kg of body weight per day. Children 3 to 6 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 8 to 10 mcg per kg of body weight per day. Children 0 to 3 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 10 to 15 mcg per kg of body weight per day. For thyroid cancer: Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually more than 2 microgram (mcg) per kilogram (kg) of body weight per day. Children—Use and dose must be determined by your doctor.
• For oral dosage form (tablet):For hypothyroidism: Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 1.6 microgram (mcg) per kilogram (kg) of body weight per day but may be less in older adults. Your doctor may adjust your dose as needed or tolerated. Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated. Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated. Children 1 to 5 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 5 to 6 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated. Children 6 to 12 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 6 to 8 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated. Children 3 to 6 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 8 to 10 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated. Children 0 to 3 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 10 to 15 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Use the oral liquid within 15 days after opening the pouch. Keep the ampules in the pouch until you are ready to use them.

• Should you take your thyroid medication at night?
• Can Tirosint cause weight gain or loss?
• How long does Tirosint stay in your system?
• Is Tirosint gluten-free?
• Does levothyroxine cause weight gain or loss?
• What can I eat for breakfast after taking levothyroxine?
• Can I take other medications with levothyroxine?
• How soon after taking levothyroxine can I take omeprazole?
• Does levothyroxine cause hair loss?

View more FAQ