Question: Can hyperthyroidism cause shortness of breath?

Dr. Hibberd's Answer:

When uncontrolled, hyperthyroidism can cause shortness of breath. A severe form of hyperthyroidism, called a "thyroid storm" is a medical emergency and can actually cause sudden death, often from tachyarrythmias (various rapid heart rates). Hyperthyroidism will often cause rapid heart rates and even arrythmias (irregular heart rhythms). These rapid heart rates are usually perceived as shortness of breath. In patients with impaired circulation to the heart muscle, tachyarrythmias can generate overt heart failure, myocardial infarction, and collapse.

If you develop shortness of breath with hyperthyroidism, seek immediate medical attention, preferably in the Emergency Department of a nearby hospital. Sometimes the medications we use to control rapid heart rates and tremor in hyperthyroidism may precipitate wheezing in smokers and those prone to asthma, and urgent evaluation would be prudent.