Synthroid Dosage Guide

Synthroid (levothyroxine) treats hypothyroidism (low thyroid hormone) and different types of … Levothyroxine should not be used for the treatment of obesity or for the purpose of losing weight. If taken in large amounts, levothyroxine may cause serious unwanted effects. The dose of this medicine will be different for different patients. 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.

• So, in order to diagnose the disease accurately, given the non-specific symptoms, you must use the TSH level as a screening tool to assist in the family history and signs and symptoms that you have come across.
• These could be symptoms of severe hypothyroidism, called myxedema coma, which may be life-threatening and requires immediate medical attention.
• Adding plans allows you to compare formulary status to other drugs in the same class.

The right way, every day

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. Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur.

I review with the patients the important issues about how to take the medication, as consistency is really the key message. I talk about the fact that it’s important to take the medication in the same timing and pattern each day, take it on an empty stomach minutes before they eat. I also review the safety and risks of taking thyroid medication.

4 Acute Adrenal Crisis in Patients with Concomitant Adrenal Insufficiency

Circulating thyroid hormones are greater than 99% bound to plasma proteins, including thyroxine-binding globulin (TBG), thyroxine-binding prealbumin (TBPA), and albumin (TBA), whose capacities and affinities vary for each hormone. The higher affinity of both TBG and TBPA for T4 partially explains the higher serum levels, slower metabolic clearance, and longer half-life of T4 compared to T3. Protein-bound thyroid hormones exist in reverse equilibrium with small amounts of free hormone. Many drugs and physiologic conditions affect the binding of thyroid hormones to serum proteins see DRUG INTERACTIONS. Thyroid hormones do not readily cross the placental barrier see Use In Specific Populations. Synthroid is prescribed in phentermine synthroid tablets that range from 25 to 300 mcg in strength and is usually taken once a day with a full glass of water (about 8 ounces) 30 to 60 minutes before breakfast for best adsorption into the body.

In addition to testing TSH, sometimes it may be important to run other labs such as a free T4, in addition to the TSH, to ensure you have accurate dosing in the medication. So, getting the patients on the right dose, but maintaining them on the right dose, is also very important. RxList does not provide medical advice, diagnosis or treatment. SYNTHROID is contraindicated in patients with uncorrected adrenal insufficiency see WARNINGS AND PRECAUTIONS. Administer SYNTHROID at least 4 hours before or after drugs known to interfere with SYNTHROID absorption see DRUG INTERACTIONS. Our Synthroid Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

• Walnuts, grapefruit juice, and dietary fiber can also make Synthroid less effective.
• It’s important to always take your medication exactly as your doctor prescribed.
• In addition, many drugs and foods affect T4 absorption see Drug Interactions (7).

Long-term carcinogenicity studies in animals to evaluate the carcinogenic potential of levothyroxine have not been performed. Studies to evaluate mutagenic potential and animal fertility have not been performed. If cardiac symptoms develop or worsen, reduce the SYNTHROID dose or withhold for one week and restart at a lower dose. SYNTHROID is contraindicated in patients with uncorrected adrenal insufficiency see Warnings and Precautions (5.4). Administer SYNTHROID at least 4 hours before or after drugs known to interfere with SYNTHROID absorption see Drug Interactions (7.1).

Drugs That May Decrease Conversion of T4 to T3

• Do not administer in foods that decrease absorption of SYNTHROID, such as soybean-based infant formula see Drug Interactions (7.9).
• Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases.
• However, elderly patients are more likely to have age-related heart or blood vessel problems, which may require caution and an adjustment in the dose for patients receiving levothyroxine.
• If so, advise them to stop biotin supplementation at least 2 days before assessing TSH and/or T4 levels see Dosage and Administration (2.4) and Drug Interactions (7.10).

A temporary loss of hair may occur during the first few months of levothyroxine therapy. 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.

1 Serious Risks Related to Overtreatment or Undertreatment with SYNTHROID

Consumption of certain foods may affect SYNTHROID absorption thereby necessitating adjustments in dosing see Dosage and Administration (2.1). Soybean flour, cottonseed meal, walnuts, and dietary fiber may bind and decrease the absorption of SYNTHROID from the gastrointestinal tract. Grapefruit juice may delay the absorption of levothyroxine and reduce its bioavailability. SYNTHROID may reduce the therapeutic effects of digitalis glycosides.

Careful dose titration is necessary to avoid the

54% of prescriptions for SYNTHROID were not protected with a DAW or state-specific language in one study. A levothyroxine product that is not therapeutically equivalent with SYNTHROID might not have the exact same effect on the patient’s TSH as SYNTHROID. One is that the peak therapeutic effect of levothyroxine at a given dose may not be obtained for 4-6 weeks after medication is ingested. Please see the additional Important Safety Information at the end of this video, including the BOXED WARNING regarding inappropriate treatment for obesity or for weight loss. Biotin supplementation is known to interfere with thyroid hormone immunoassays that are based on a biotin and streptavidin interaction, which may result in erroneous thyroid hormone test results. Stop biotin and biotin-containing supplements for at least 2 days prior to thyroid testing.

Biochemical assessment incorporated measurement of serum TSH, T3, and T4. TSH lower limit of quantification was 0.2 mIU/L and upper limit of normal was 5.6 mIU/L, as indicated by the shaded area. SYNTHROID is not indicated for treatment of hypothyroidism during the recovery phase of subacute thyroiditis. The goal is to achieve steady TSH levels within the appropriate therapeutic range. Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter OTC) medicines and herbal or vitamin supplements.