Levothroid Side Effects

Side effects of Levothroid typically occur when your dosage is too high. Because Levothroid side effects can be dangerous, be sure to report anything that "just does not seem right" to your healthcare provider right away. Some side effects of Levothroid can include hyperactivity, insomnia, and hair loss. You should also seek immediate medical attention if you develop any signs of an allergic reaction, such as difficulty breathing or an unexplained rash.

 

An Introduction to Levothroid Side Effects

As with any medicine, side effects are possible with Levothroid® (levothyroxine sodium). However, not everyone who takes the drug will experience side effects. In fact, most people tolerate it quite well.
 
(This article covers many, but not all, of the possible side effects with Levothroid. Your healthcare provider can discuss a more complete list of side effects with you.)
 

Possible Levothroid Side Effects

Side effects typically occur when the Levothroid dosage is too high. Too much Levothroid causes symptoms of an overactive thyroid (known medically as hyperthyroidism). These symptoms can be dangerous, and any of these symptoms should be reported to your healthcare provider (as they may signal that your Levothroid dosage needs to be decreased). These side effects may include:
 
As with any medication, Levothroid can also cause allergic reactions. Seek medical attention immediately if you develop signs of an allergic reaction, including:
 
  • An unexplained rash or hives
  • Itching
  • Wheezing or difficulty breathing
  • Unexplained swelling (especially of the lips, mouth, or throat).
     
(Levothroid Side Effects Continued: Page 2)
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;