Review: could Synthroid cause Atrial Fibrillation?


Atrial fibrillation is found among people who take Synthroid, especially for people who are female, 60+ old , have been taking the drug for 10+ years, also take medication Coumadin, and have Atrial fibrillation . We study 102,844 people who have side effects while taking Synthroid from FDA and social media. Among them, 1,788 have Atrial fibrillation. Find out below who they are, when they have Atrial fibrillation and more.

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Synthroid has active ingredients of levothyroxine sodium. It is often used in hypothyroidism. (latest outcomes from Synthroid 104,321 users)

Atrial Fibrillation

Atrial fibrillation (fibrillation of the muscles of the atria of the heart) has been reported by people with breathing difficulty, hypotension, weakness, diarrhea, arrhythmias (latest reports from 98,371 Atrial fibrillation patients).

On Aug, 23, 2016

102,844 people reported to have side effects when taking Synthroid.
Among them, 1,788 people (1.74%) have Atrial Fibrillation

Number of reports submitted per year:

Could Synthroid cause Atrial fibrillation?

Time on Synthroid when people have Atrial Fibrillation *:

  • < 1 month: 17.95 %
  • 1 - 6 months: 7.69 %
  • 6 - 12 months: 5.13 %
  • 1 - 2 years: 5.13 %
  • 2 - 5 years: 12.82 %
  • 5 - 10 years: 15.38 %
  • 10+ years: 35.9 %

Gender of people who have Atrial Fibrillation when taking Synthroid *:

  • female: 74.87 %
  • male: 25.13 %

Age of people who have Atrial Fibrillation when taking Synthroid *:

  • 0-1: 0.0 %
  • 2-9: 0.0 %
  • 10-19: 0.2 %
  • 20-29: 0.46 %
  • 30-39: 1.37 %
  • 40-49: 3.71 %
  • 50-59: 16.51 %
  • 60+: 77.76 %

Severity if Atrial Fibrillation when taking Synthroid **:

  • least: 0.0 %
  • moderate: 57.14 %
  • severe: 42.86 %
  • most severe: 0.0 %

How people recovered from Atrial Fibrillation **:

  • while on drug: 22.22 %
  • after off the drug: 22.22 %
  • not yet: 55.56 %

Top conditions involved for these people *:

  • Atrial Fibrillation (222 people)
  • Hypothyroidism (187 people)
  • Osteoporosis (145 people)
  • Hypertension (130 people)
  • Thyroid Disorder (95 people)

Top co-used drugs for these people *:

  • Coumadin (480 people)
  • Lasix (464 people)
  • Aspirin (381 people)
  • Digoxin (342 people)
  • Lipitor (224 people)

* Approximation only. Some reports may have incomplete information.

** Reports from social media are used.

How to use the study: print a copy of the study and bring it to your health teams to ensure drug risks and benefits are fully discussed and understood.

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NOTE: The study is based on active ingredients and brand name. Other drugs that have the same active ingredients (e.g. generic drugs) are NOT considered.

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