You may not be able to take Thyroxine if you have certain medical conditions. 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.
Thyroxine should not be used to treat obesity or weight problems. Dangerous side effects or death can occur from the misuse of this medicine, especially if you are taking any other weight-loss medications or appetite suppressants.
Q: Is there enough lactose in Thyroxine tablets to cause a problem for a lactose sensitive person?
A: Thyroxine (trade names: Synthroid, Levoxyl, Levothroid, and Unithroid), a thyroid hormone, is used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. Synthroid (Thyroxine) con inactive ingredients acacia, confectioner's sugar, lactose monohydrate, magnesium stearate, povidone, talc, and color additives. The lactose in Synthroid could potentially trigger symptoms in people with lactose intolerance. Lactose intolerance is an inability to digest lactose, which is the major sugar found in milk, but also an ingredient in some foods and medications. Signs of lactose intolerance include nausea, cramps, bloating, gas, and diarrhea. Usually, the symptoms will begin 30 minutes to 2 hours after taking your Synthroid pill. Two other brands of Thyroxine are Levoxyl and Levothroid they are free of lactose. For more specific information, consult with your doctor or pharmacist for guidance based on your specific condition and current medications. Shereen A. Gharbia, PharmD
Oral: Administer Thyroxine on an empty stomach (acidity increases absorption), at least 30 to 60 minutes before breakfast or 3 to 4 hours after dinner. Do not administer Thyroxine within 4 hours of administration of products that may contain iron or calcium. Do not administer Thyroxine in conjunction with antacids or proton pump inhibitors.
Capsule: Swallow whole; Do not crush or cut.
Tablet: May crush into 5 to 10 mL of water and drank immediately. If swallowing tablet whole, administer with a full glass of water to prevent dysphagia.
Solution: Give either undiluted (directly squeeze contents into mouth) or diluted in water only (squeeze contents into water, stir, and drink immediately).
Intravenous Thyroxine is exclusively for use in the hospital setting in which vital signs can undergo close monitoring.
In cases where the patient can not tolerate anything by mouth due to an underlying problem, the Thyroxine capsules are usable as a suppository and are well absorbed.
For the treatment of hypothyroidism (oral): Adults who are healthy and who have a diagnosis of hypothyroidism for a few months should receive an initial dose of 1.6 mcg/kg/day with a 12.5 to 25 mcg/day dose adjustment every 6 to 8 weeks as needed. Adults with cardiac disease or elderly over 65 years old and hypothyroidism should receive an initial dose of 25 mcg/day with dose adjustment of 12.5 to 25 mcg every 4 to 6 weeks as needed. Pregnant patients with newly diagnosed hypothyroidism should receive initial treatment at 1.8 mcg/kg/day. Adjust dose every 4 weeks as needed. If a patient has a diagnosis of hypothyroidism prior to pregnancy, adjust the dose of Thyroxine as needed. After pregnancy, the dose of Thyroxine should decrease to 1.6 mcg/kg/day.
For the treatment of myxedema coma (IV) or severe hypothyroidism: 200 to 400 mcg initial IV loading dose followed by a daily dose of 1.2 mcg/kg/day with consideration to use lower doses in patients with a history of cardiac disease, arrhythmia, or older patients. Switch to oral therapy (8mcg/kg/day) when symptoms resolve. The equivalence between intravenous to oral is 2 to 1 (for example 200 mcg IV of Thyroxine is equal to 100 mcg of oral Thyroxine )
For organ recovery from a cadaver (IV):20mcg IV bolus to the donor, followed by 10 mcg/hour continuous infusion. Given with methylprednisolone, dextrose, and insulin.
- Do not use this medicine (Thyroxine tablets) to treat obesity or for weight loss. Very bad and sometimes deadly side effects may happen with this medicine (Thyroxine tablets) if it is taken in large doses or with other drugs for weight loss. Talk with the doctor.
8. Cautions with other medicines
Some medicines can interfere with thyroid hormones, so the dose of Thyroxine may need to be changed. They include:
- medicines for seizures, carbamazepine and phenytoin
- oestrogens - such as in combined contraceptive pills or hormone replacement therapy (HRT)
Thyroxine can change how other medicines work, so their doses may need to be altered. These medicines include:
- medicines for diabetes - either insulin or tablets
- the blood thinning medicine, warfarin
Some medicines shouldn't be taken at the same time of day as Thyroxine as they can reduce the amount of Thyroxine your body takes in, including:
- calcium salts
- iron salts
- orlistat, a medicine used for weight loss
- sucralfate, a medicine used to treat stomach ulcers
- some cholesterol-lowering medicines such as colestyramine, colestipol or colesevelem
Read the information leaflet supplied with these medicines or speak to your pharmacist for advice on how much time to leave between taking these medicines and taking Thyroxine.
Thyroxine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- weight gain or loss
- changes in appetite
- changes in menstrual cycle
- sensitivity to heat
- hair loss
- joint pain
- leg cramps
What other drugs will affect Thyroxine?
Many other medicines can be affected by your thyroid hormone levels. Certain other medicines may also increase or decrease the effects of Thyroxine.
Certain medicines can make Thyroxine less effective if taken at the same time. If you use any of the following drugs, avoid taking them within 4 hours before or 4 hours after you take this medicine:
Many drugs can interact with Thyroxine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.
Your doctor will do regular blood tests to check the levels of thyroid hormones in your body before and after starting Thyroxine.
These will allow your doctor to adjust the dose to suit you.
At the start of treatment you can expect to have blood tests often. Once your hormone levels are stable, you'll usually have a blood test after 4 to 6 months, and after that once a year.
You may need blood tests more often if you:
- are pregnant
- start or stop a medicine that can interfere with Thyroxine
- have any symptoms that could mean your dose is not quite right
Interactions that can make your drugs less effective
When Thyroxine is less effective: When you take Thyroxine with certain drugs, it may not work as well to treat your condition. This is because the amount of Thyroxine in your body may be decreased. Examples of these drugs include:
- Rifampin and anti-seizure drugs such as carbamazepine and phenobarbital.
- Calcium carbonate or ferrous sulfate. Take Thyroxine at least four hours before or after taking these medications to help make sure that Thyroxine works properly.
- Colesevelam, cholestyramine, colestipol, kayexalate, or sevelamer. Take Thyroxine at least 4 hours before taking these medications to help make sure that Thyroxine works properly.
- Simethicone and antacids such as aluminum or magnesium.
- Cancer drugs that belong to the tyrosine-kinase inhibitors class, such as imatinib.
When other drugs are less effective: When certain drugs are used with Thyroxine, they may not work as well. This is because the amount of these drugs in your body may be decreased. Examples of these drugs include:
- Diabetes drugs, such as insulin, metformin, nateglinide, glipizide, and pioglitazone. If you take any of these diabetes drugs with Thyroxine, your doctor may need to increase your dosage of these drugs.
- Digoxin. If you take this drug with Thyroxine, your doctor may need to increase your dosage of digoxin.
- Theophylline. Your doctor may monitor the levels of theophylline in your body if you take it with Thyroxine.
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.
What Is Thyroxine (Synthro >
Thyroxine is a synthetic thyroid hormone used to treat hypothyroidism, a condition in which the thyroid gland doesn't produce enough thyroid hormone.
The drug is available under the brand names Levothroid, Levoxyl, Levo-T, Synthroid, Tirosint, and Unithroid.
Thyroid hormones affect the metabolism of protein, fats, and carbohydrates. They also affect a person's growth and development.
If untreated, hypothyroidism can lead to poor growth, slow speech, loss of energy, weight gain, hair loss, dry skin, and increased sensitivity to cold temperatures.
Thyroxine can help reverse these symptoms. The drug can also help treat the congenital form of hypothyroidism, as well as an enlarged thyroid gland (goiter) and thyroid cancer.
Thyroxine has been available in the United States since the 1950s, but the Food and Drug Administration (FDA) didn't approve it until 2000.
Q: I am a 60-year-old female, have a hypothyroid problem, and take Oroxine 50 mcg for the last three years. My TFT is normal. Is Eltoxin better than Oroxine, or is any thyroid tablet okay? And is that true that one should not change from one brand to another?
A: Oroxine and Eltoxin, which are not available in the United States, are the brand names for Thyroxine. Thyroxine is used to replace thyroid hormone when your body does not make enough on its own. It is one of the most commonly used medications for hypothyroidism. Generally, it is not recommended to change brands of Thyroxine because even small changes in the amount your body absorbs could change your thyroid hormone levels and cause symptoms. Your doctor can determine your thyroid levels by doing a blood test and then check to make sure you are getting the proper dose of medicine. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Michelle McDermott, RPh, PharmD
Uses of Thyroxine Tablets:
- It is used to add thyroid hormone to the body.
- It is used to manage thyroid cancer.
- It may be given to you for other reasons. Talk with the doctor.
Is Thyroxine sodium available as a generic drug?
GENERIC AVAILABLE: Yes. Generic and branded tablets of Thyroxine may differ:
- in the amount of Thyroxine they contain,
- the absorption of the Thyroxine into the body, and
- the distribution of Thyroxine throughout the body.
This means that ingestion of 1 mg of generic Thyroxine may not have the same effect on the body as 1 mg of another generic or branded Thyroxine. Practically speaking, this means that when changing between Thyroxine manufactured by different pharmaceutical companies, a change in dose may be necessary to maintain the desired effect or to prevent toxicity. When switching between brands or generics, it is important to ensure that both preparations are equivalent or to check blood thyroid levels weekly.
How it works
Thyroxine belongs to a class of drugs called hormones. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.
Thyroxine works by providing the thyroid hormone that your thyroid gland would produce if it were working normally.
Thyroxine oral tablet doesn’t cause drowsiness, but it can cause other side effects.