Synthroid

Thyroid hormone produced by your thyroid gland. Thyroid hormones are key in governing metabolism, body temperature, heart rate, and other processes. When your hormone levels are too low, thyroid replacement hormones can help restore them to normal.

Synthroid is an L-thyroxine (T4) used in adult and pediatric patients, including neonates, for:

Hypothyroidism: Used as replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism.

Pituitary thyrotropin (TSH, thyroid-stimulating hormone).

Those who need surgery and radioiodine therapy to manage a type of thyroid cancer called well-differentiated thyroid cancer.

Decreasing the size of enlarged thyroid glands (goiter).

Follow all directions given to you by your doctor and read all documents provided, including the full Prescribing Information, FDA-Approved Product Labeling, Instructions for Use, and Medication Guide before using Synthroid. However, the following is a synopsis of the general guidelines for the use of Synthroid:

• Synthroid works best when taken on an empty stomach, 30-60 minutes before breakfast. Follow your doctor's dose directions and try to take your medication at the same time every day.
• Infants and children who are unable to swallow tablets can be given Synthroid by breaking the tablet, mixing it with a small amount (5-10ml or 1-2 teaspoons) of water, and providing the mixture quickly with a spoon or dropper. Do not store the crushed tablet/water mixture, and do not combine it with foods that reduce levothyroxine absorption, such as soybean-based infant formula.
• Children's levothyroxine doses are based on their weight. If your child gains or loses weight, their dosage requirements may fluctuate.
• In the elderly and patients with cardiovascular disease, Synthroid should be started at lower doses than those recommended in younger patients or those without heart disease.
• It may take many weeks for your body to respond to Synthroid. Even if you feel OK, continue taking this medication because you may need it for the rest of your life.
• Lab and/or medical tests such as thyroid function or TSH levels should be done while you are taking this medication.

The side effects of Synthroid are similar to the symptoms of hyperthyroidism (a condition that causes high thyroid hormone levels). They include:

• Irregular heartbeat.
• Chest pains or shortness of breath.
• Leg cramps.
• Headaches.
• Nervousness.
• Hives or skin rash.
• Irritability or trouble sleeping.
• Tremors.
• Muscle weakness.
• Change in appetite or weight loss.
• Vomiting or diarrhea.
• Sweating or sensitivity to heat.
• Fever.
• Changes in menstrual period.
• Hair loss.
• Weight gain is possible to gain weight while taking Synthroid if the dose is insufficient to raise your thyroid hormone levels to the therapeutic range. If you gain weight while taking Synthroid (levothyroxine), tell your doctor.

Some individuals may experience serious side effects while using Synthroid. These side effects may require immediate medical attention. If you experience any of the following, contact your healthcare provider or seek emergency medical help:

• Heart attack or heart failure.
• Fast heart rate.

These are not all of the possible side effects of Synthroid. You should always seek medical advice from your healthcare provider for any questions or concerns about your medical condition or treatment. Read all patient information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the Food and Drug Administration at www.fda.gov/medwatch or 1-800-FDA-1088.

Before starting Synthroid, it is crucial to discuss any existing health conditions with your healthcare provider. You should be sure that your healthcare provider is aware of all your medical conditions, including if you have:

• Uncontrolled or untreated adrenal gland disorder.
• A thyroid disorder called thyrotoxicosis.
• A thyroid nodule.
• Heart problems include coronary artery disease, a heart attack, stroke, blood clot, or blood clotting condition.
• Diabetes.
• Anaemia (low red blood cell count).
• Low bone mineral density or osteoporosis.
• Difficulties with your pituitary gland.
• Any food or drug allergies.
• Kidney disease.
• Before using Synthroid (levothyroxine), inform your doctor if you are allergic to it or have any other allergies. This product may include inactive ingredients, which might trigger allergic reactions or other issues. Contact your chemist for additional information.
• Synthroid is not recommended for the treatment of obesity or weight disorders and dangerous life-threatening side effects may occur from the misuse of this medication.
• Avoid grapefruit juice, infant soy formula, soybean flour, cotton seed meal, walnuts, and high dietary fiber meals, as these can reduce your body's absorption of levothyroxine.

Contraindications are certain health problems or situations in which a person should avoid taking a drug for safety reasons. If you have any of the below conditions or if any of the following apply to you, please notify your healthcare practitioner because Levothyroxine (Synthroid) is not safe for you to consume.

• Uncorrected adrenal insufficiency.
• Myxedema coma (severe hypothyroidism that may be life-threatening and requires immediate medical attention)

Typically, you'll need to take levothyroxine (Synthroid) for 4 to 6 weeks to fully benefit from this drug. However, some people may find improvements in their symptoms sooner. If you are taking levothyroxine (Synthroid) for the first time, it may take months for your doctor to determine the appropriate dose for you.

When Synthroid is taken with other prescription drugs, over-the-counter medications, vitamins, and supplements, it may change how they work or increase the frequency or severity of side effects. Make sure that you tell your healthcare professional about anything that you are taking, and if you use any of the following drugs, avoid taking them within 4 hours before or 4 hours after you take Synthroid:

-Other medications that increase thyroid hormone levels, including liothyronine, Armour Thyroid, Euthyrox, Levoxyl, NP Thyroid, Tirosint, and Cytomel.

• Calcium carbonate (Alka-Mints, Caltrate, Os-Cal, Oyster Shell Calcium, Rolaids Soft Chew, Tums, and others).
• Cholestyramine, colesevelam, colestipol.
• Ferrous sulfate iron supplement.
• Sucralfate.
• Sevelamer.
• Lanthanum.
• Sodium polystyrene sulfonate (Kalexate, Kayexalate, Kionex).
• Stomach acid reducers - esomeprazole, lansoprazole, omeprazole, rabeprazole, and others.
• Simethicone.
• Antacids that contain aluminum or magnesium - Gaviscon, Maalox, Milk of Magnesia, Mintox, Mylanta, Pepcid Complete, and others.

This is not a full list of drug interactions and it is important to speak to your healthcare provider first.

Synthroid’s dosage will differ for each person. Your healthcare provider will determine your dose based on several factors, including your age, medical condition, and thyroid hormone level.

The typical dose of Synthroid ranges from 13 mcg to 200 mcg. It should be taken by mouth once daily on an empty stomach.

If you miss a dose, take the medication as soon as possible, but skip the missed dose if it is almost time for the next dose. Do not take two doses at the same time.

Store your medication at room temperature, and away from moisture or heat. Additionally, keep out of reach of children.

Do not keep expired or no longer needed medicines and ask your healthcare provider about how you should dispose of any unused medicine.

AbbVie manufactures the brand-name Synthroid.

There are several lower-cost generics of Synthroid available.

Do not stop taking Synthroid or change your dose without talking to your doctor first. They can decide to lower your dose gradually to wean you off of it. If you develop new symptoms of hypothyroidism, you need to call your doctor right away.

Talk to your doctor if you are already pregnant or if you have any plans to become pregnant. They will know or recommend what is best for you.

If you become pregnant while taking Synthroid, do not discontinue taking the medication without consulting your doctor. Low thyroid hormone levels during pregnancy may affect both you and your baby. Your dosage requirements may change during pregnancy.

Synthroid is generally considered safe to use when breastfeeding for both the mother and the infant. It can also assist breastfeeding mothers to enhance their milk production. While an almost undetectable quantity of Synthroid enters the milk, the drug's adverse effects are not passed on to the infant. However, talk to your doctor if you are already breastfeeding or if you have any plans to breastfeed. They will know or recommend what is best for you.