What is Levoxyl?

Levoxyl is Pfizer’s brand name for a medication containing the active ingredient levothyroxine, a hormone similar to thyroxine, or T4, the main hormone that is made and released by your thyroid gland.

What is Levoxyl used for?

Levoxyl is used to treat underactive thyroids by replacing or giving extra levothyroxine to those who do not naturally produce enough of this hormone. It can also be used to treat people who need surgery and radioiodine therapy to manage a type of thyroid cancer called well-differentiated thyroid cancer. Both children and adults can be treated with Levoxyl.

Levoxyl cost

Levoxyl costs depend on health plan coverage as well as the drug prescribed. You or your doctor can use eNavvi to determine which version of this drug is within coverage and if there are any prior authorizations or step-therapy requirements.

Levoxyl generic name

Levoxyl is available in its generic form under the same name as its active ingredient, levothyroxine. However, it is important to know that the generic form of Levoxyl may contain more variations in potency and additives.

Levothyroxine vs Levoxyl

Levothyroxine is the active ingredient in Levoxyl. Levothyroxine in its generic form is different from Levoxyl because of inactive filler ingredients.

Levoxyl vs Synthroid

Synthroid is another brand name medication containing levothyroxine as its active ingredient. Although Synthroid and Levoxyl share the same active ingredient, they contain different inactive filler ingredients. Both products are considered by the FDA to be therapeutically equivalent, meaning that they are expected to produce the same clinical effect and be equally safe for consumption. While these medications are legally allowed to be substituted for each other, it is not advised to switch frequently between different forms of levothyroxine because this can cause enough variation to cause a noticeable effect on thyroid hormone levels and symptom control.

Side effects:

The most common side effects of Levoxyl are listed on Pfizer’s website as follows:

  • irregular heartbeat
  • chest pain
  • shortness of breath
  • leg cramps
  • headache
  • nervousness
  • hives or skin rash
  • irritability
  • sleep problems (insomnia)
  • tremors
  • muscle weakness
  • change in appetite
  • weight loss
  • vomiting
  • diarrhea
  • sweating a lot
  • heat intolerance
  • fever
  • changes in menstrual period

Levoxyl can cause more serious side effects in some people who have other medical conditions.T

Those with heart conditions should be aware that they may experience an increased heart rate, chest pain and irregular heartbeat. The risk of developing heart problems may be greater if you are elderly, have heart problems, or if you take too much Levoxyl. Levoxyl can also make it harder for diabetics to control their blood sugar levels, which can cause hyperglycemia while taking this medication. If you are diabetic and taking Levoxyl, it is recommended that you check your blood sugar levels closely after starting, changing, or
stopping treatment with Levoxyl, and tell your healthcare provider if there are any changes. Your healthcare provider may have to change your diabetes treatment plan.

Can Levoxyl cause weight gain?

Levoxyl is more likely to cause weight loss as a side effect. Weight gain on Levoxyl may be a sign of under treatment according to the American Thyroid Association.

Does Levoxyl contain gluten?

Levoxyl does not contain gluten, and is therefore considered gluten-free. The inactive ingredients in Levoxyl are microcrystalline cellulose, croscarmellose sodium, magnesium stearate, calcium sulfate dihydrate, sodium bicarbonate, and coloring additives.


The information included in this page is not a substitute for medical advice. The list of side effects may not include all side effects as drugs can affect all people differently. Any dosage information may not include all dosage information. It is important to discuss with a medical professional that knows your medical history well which dosage is right for you and if there are any potential risks or possible side effects. Our goal is to provide relevant information but this page may not include all up-to-date information.