(levothyroxine sodium)

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What are the possible side effects of LEVOXYL?

What are the possible side effects of LEVOXYL?

LEVOXYL can cause serious side effects, including:
  • heart problems. You may experience an increased heart rate, chest pain and irregular heartbeat. Your risk of developing heart problems may be greater if you are elderly, have heart problems, or if you take too much LEVOXYL. Your healthcare provider may reduce your dose or stop treatment with LEVOXYL for a while if you develop heart problems.
  • worsening diabetic control. If you are a diabetic, it may be harder to control your blood sugar levels causing hyperglycemia while taking LEVOXYL. 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.
  • weak or brittle bones. Your risk of developing weak or brittle bones may be greater if you are post-menopausal and are taking high doses of LEVOXYL for a long period.
The most common side effects of LEVOXYL include:
  • 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
Other side effects may include:
  • partial hair loss during the first months of treatment with LEVOXYL. This usually lasts a short period of time.
These are not all the possible side effects of LEVOXYL. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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