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Levoxyl Side Effects
Even though most people do not experience problems when taking Levoxyl, side effects are possible. Some common side effects include insomnia, hair loss, and difficulty breathing. Side effects typically occur when your dosage is too high. Because many side effects of the drug can be dangerous, it is important to contact your healthcare provider right away if you develop any problems.
An Introduction to Levoxyl Side Effects
As with any medicine, side effects are possible with Levoxyl® (levothyroxine sodium). However, not everyone who takes the drug will have problems. In fact, most people tolerate it quite well.
(This article covers many, but not all, of the possible side effects with Levoxyl. Your healthcare provider can discuss a more complete list of Levoxyl side effects with you.)
Side effects typically occur when the Levoxyl dosage is too high. Too much Levoxyl 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 dosage needs to be decreased. These Levoxyl side effects may include:
- Insomnia (see Levoxyl and Insomnia)
- Emotional changes
- Hair loss (see Levoxyl and Hair Loss)
- Flushing
- Broken bones or other signs of weakened bones
- Menstrual problems or fertility problems
- Shakiness or muscle weakness
- Heart palpitations
- A rapid heart rate (tachycardia)
- Heart failure, chest pain, or a heart attack
- Difficult or painful breathing
- An increased appetite, along with weight loss
- Feeling hot all the time and increased sweating
- Fever
- Hyperactivity, nervousness, anxiety, or irritability
- High blood pressure (hypertension)
- Diarrhea, vomiting, or abdominal cramps (stomach cramps)
- Seizures.
As with any medication, Levoxyl can also cause allergic reactions. Seek medical attention immediately if you develop signs of an allergic reaction, such as:
- An unexplained rash
- Hives
- Itching
- Wheezing or difficulty breathing
- Unexplained swelling (especially of the lips, mouth, or throat).
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD