"Oct. 28, 2011 - Nine out of 10 "thyroid support" pills tested by Mayo Clinic researchers contain "risky" levels of thyroid hormones.
A wide range of supplements that claim to support or improve thyroid function are available online an"...
Synthroid Side Effects Center
Medical Editor: Charles Patrick Davis, MD, PhD
Synthroid (levothyroxine sodium) is a synthetic compound identical to T4 (levothyroxine) produced by the human thyroid gland. Levothyroxine is the generic name for the drug. The drug is used to treat hypothyroidism due to many etiologies (for example, thyroid removal, thyroid atrophy, functional T4 deficiency, radiation treatment of the thyroid, and other causes). It is also used for pituitary TSH suppression. Common side effects include: fever, hot flashes, sensitivity to heat, headache, nervousness, nausea, insomnia, and transient hair loss. Some women experience menstrual changes. Serious side effects -- such as rapid heartbeats, chest pain (or both) -- are cause for patients to notify their doctors immediately.
Synthroid is prescribed in 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. Children can take the medicine if the tablet is crushed and put into about 1 to 2 teaspoons of water; do not store or delay giving this crushed pill suspension. Doctors often may have to slowly increase the dose; patients should not increase or decrease this medication themselves. Because some preparations of the drug may contain iodine or lactose, patients should tell their doctors about such allergies or reactions to these components. Many drugs can inhibit Synthroid's adsorption by the body; other medications may increase or decrease its effectiveness once it is adsorbed. Providing a complete list of medications to the doctor will help with getting the correct dose established for each individual patient. Pregnant and lactating females need to discuss the dose and use of this medication with their caregivers.
Our Synthroid Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
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.
What is Patient Information in Detail?
Easy-to-read and understand detailed drug information and pill images for the patient or caregiver from Cerner Multum.
Synthroid in Detail - Patient Information: Side Effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
- sleep problems (insomnia);
- feeling nervous or irritable;
- fever, hot flashes, sweating;
- pounding heartbeats or fluttering in your chest;
- changes in your menstrual periods; or
- appetite changes, weight changes.
Less serious side effects may include mild hair loss.
Read the entire detailed patient monograph for Synthroid (Levothyroxine Sodium) »
What is Patient Information Overview?
A concise overview of the drug for the patient or caregiver from First DataBank.
Synthroid Overview - Patient Information: Side Effects
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these unlikely but serious effects of high thyroid hormone levels occur: increased sweating, sensitivity to heat, mental/mood changes (such as nervousness, mood swings), tiredness, diarrhea, shaking (tremor), headache, shortness of breath.
Get medical help right away if any of these rare but serious effects of high thyroid hormone levels occur: chest pain, fast/pounding/irregular heartbeat, swelling hands/ankles/feet, seizures.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Read the entire patient information overview for Synthroid (Levothyroxine Sodium)»
What is Prescribing information?
The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.
Synthroid FDA Prescribing Information: Side Effects
Musculoskeletal: tremors, muscle weakness;
Dermatologic: hair loss, flushing;
Endocrine: decreased bone mineral density;
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 Synthroid (Levothyroxine Sodium) »
Additional Synthroid Information
Synthroid - User Reviews
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