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Levothyroxine Injection Solution

Generic Name: Levothyroxine Injection Solution (LEE voe thye ROX een)

  • Do not use levothyroxine injection solution to treat obesity or for weight loss. Very bad and sometimes deadly side effects may happen with this medicine if it is taken in large doses or with other drugs for weight loss. Talk with the doctor.

Uses of Levothyroxine Injection Solution:

  • It is used to add thyroid hormone to the body.
  • It may be given to you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take Levothyroxine Injection Solution?

  • If you have an allergy to levothyroxine or any other part of levothyroxine injection solution.
  • If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
  • If you have any of these health problems: Overactive thyroid gland, recent heart attack, or weak adrenal gland.

This is not a list of all drugs or health problems that interact with this medicine.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take levothyroxine injection solution with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Levothyroxine Injection Solution?

For all patients taking this medicine:

  • Tell all of your health care providers that you take levothyroxine injection solution. This includes your doctors, nurses, pharmacists, and dentists.
  • Do not run out of this medicine.
  • It may take several weeks to see the full effects.
  • If you have high blood sugar (diabetes), you will need to watch your blood sugar closely.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • This medicine may cause weak bones (osteoporosis) with long-term use. Talk with your doctor to see if you have a higher chance of weak bones or if you have any questions.
  • This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking levothyroxine injection solution with your other drugs.
  • If you are 65 or older, use this medicine with care. You could have more side effects.
  • Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using levothyroxine injection solution while you are pregnant.
  • Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

Children:

  • If giving to your child, the dose of this medicine may need to be changed as your child's weight changes. Have your child's weight checked often. Talk with the doctor before changing your child's dose.
  • This medicine may affect growth in children and teens in some cases. They may need regular growth checks. Talk with the doctor.

How is this medicine (Levothyroxine Injection Solution) best taken?

Use levothyroxine injection solution as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • It is given as a shot into a vein.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

Dosage Information (comprehensive)

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Chest pain or pressure or a fast heartbeat.
  • A heartbeat that does not feel normal.
  • Shortness of breath, a big weight gain, or swelling in the arms or legs.
  • Lump on your neck.
  • Headache.
  • Feeling more or less hungry.
  • A change in weight without trying.
  • Loose stools (diarrhea).
  • Stomach cramps.
  • Throwing up.
  • Feeling irritable.
  • Feeling nervous and excitable.
  • Shakiness.
  • Not able to sleep.
  • Bothered by heat.
  • Sweating a lot.
  • Fever.
  • Leg cramps.
  • Muscle weakness.
  • Period (menstrual) changes.

What are some other side effects of Levothyroxine Injection Solution?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • Hair loss may happen in some people in the first few months of using this medicine. This most often goes back to normal.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

Side Effects (complete list)

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Levothyroxine Injection Solution?

  • If you need to store levothyroxine injection solution at home, talk with your doctor, nurse, or pharmacist about how to store it.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Check with your pharmacist about how to throw out unused drugs.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine, please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

This information should not be used to decide whether or not to take levothyroxine injection solution or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to levothyroxine injection solution. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Review Date: November 1, 2017

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