Synthroid Uses, Dosage & Side Effects

This includes prescription or nonprescription (over-the-counter OTC) medicines and herbal or vitamin supplements. Do not share this medicine with another person, even if they have the same symptoms you have. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Dosage Forms And Strengths

• Tell your doctor if you have an untreated or uncontrolled adrenal gland disorder, a thyroid disorder called thyrotoxicosis, or if you have any recent or current symptoms of a heart attack.
• Several studies have shown a relationship between TMJ disorders and hypothyroidism.
• Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see Dosage and Administration (2.4).
• All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.

The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive. Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of levothyroxine in children. However, your child’s doctor will check your child closely for heart problems during the first 2 weeks of treatment. Synthroid is a thyroid medicine that replaces a hormone normally produced by your thyroid gland to regulate the body’s energy and metabolism. It is believed that the connection lies in the effect that hypothyroidism has on the muscles, nerves, and connective tissues throughout the body, including the TMJ.

1 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Disease

Grapefruit juice may delay the absorption of levothyroxine and reduce its bioavailability. SYNTHROID may reduce the therapeutic effects of digitalis glycosides. Serum digitalis glycoside levels may decrease when a hypothyroid patient becomes vertigo synthroid euthyroid, necessitating an increase in the dose of digitalis glycosides. If you become pregnant while taking Synthroid, do not stop taking the medicine without your doctor’s advice.

• The recommended daily dosage of SYNTHROID in pregnant patients is described in Table 3.
• SYNTHROID is not indicated for suppression of benign thyroid nodules and nontoxic diffuse goiter in iodine-sufficient patients, as there are no clinical benefits and overtreatment with SYNTHROID may induce hyperthyroidism.
• The recommended starting daily dosage of SYNTHROID in pediatric patients with primary, secondary, or tertiary hypothyroidism is based on body weight and changes with age as described in Table 2.

SYNTHROID is not indicated for treatment of hypothyroidism during the recovery phase of subacute thyroiditis. Foods containing soy and cottonseed meal can make Synthroid less effective. Walnuts, grapefruit juice, and dietary fiber can also make Synthroid less effective. If you eat any of these on a regular basis, check with your doctor. Do not suddenly stop taking this medicine without first checking with your doctor. Your doctor may want you or your child to gradually reduce the amount you are using before stopping completely.

Administer SYNTHROID at least 4 hours before or after drugs known to interfere with SYNTHROID absorption see Drug Interactions (7.1). 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.

Decreased Bone Mineral Density Associated With Thyroid Hormone Over-Replacement

Treat patients with adrenal insufficiency with replacement glucocorticoids prior to initiating treatment with SYNTHROID see CONTRAINDICATIONS. Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see DOSAGE AND ADMINISTRATION. Consider the potential for food or drug interactions and adjust the administration or dosage of SYNTHROID as needed see DOSAGE AND ADMINISTRATION, DRUG INTERACTIONS and CLINICAL PHARMACOLOGY. Do not administer in foods that decrease absorption of SYNTHROID, such as soybean-based infant formula see DRUG INTERACTIONS. Treat patients with adrenal insufficiency with replacement glucocorticoids prior to initiating treatment with SYNTHROID see Contraindications (4). Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see Dosage and Administration (2.4).

Hypothyroidism can cause muscle stiffness, joint pain, and overall inflammation, all of which may contribute to the development of TMJ problems. When the muscles surrounding the TMJ become stiff and inflamed, it can hinder the joint’s ability to move smoothly. This can lead to TMJ disorder’s classic signs and symptoms, such as jaw pain, clicking, difficulty chewing, and headaches. In some cases, the joint may become dislocated or locked, causing severe discomfort and limited jaw movement.

How Long After Starting Thyroid Medication to Lose Weight?

You may need a larger dose of levothyroxine while you are pregnant. Hypothyroidism can sometimes cause infertility in men and women. Levothyroxine should not be used for the treatment of infertility unless it is caused by hypothyroidism. It is very important that your doctor check the progress of you or your child at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it. Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines.

Levothyroxine (oral route)

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. 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. Absorption of orally administered T4 from the gastrointestinal tract ranges from 40% to 80%. The majority of the SYNTHROID dose is absorbed from the jejunum and upper ileum. The relative bioavailability of SYNTHROID tablets, compared to an equal nominal dose of oral levothyroxine sodium solution, is approximately 93%. T4 absorption is increased by fasting, and decreased in malabsorption syndromes and by certain foods such as soybeans.

Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone. This hormone regulates the body’s metabolism, growth, and development. When you’re hypothyroid, you can develop various symptoms, such as fatigue, weight gain, depression, and dry skin, among others. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes.