ATLANTA, Ga. (CBS46) – Pharmaceutical company GlaxoSmithKline says it is recalling more than 593,000 asthma inhalers due to a defect.

Pharmaphorum.com reports the defect in the inhalers causes them to administer fewer doses of medicine than indicated.

The company is taking the Ventolin inhalers off the shelves, following the voluntary Level 2 recall, which affects only products in the United States. The inhalers were manufactured at the company’s plant in Zebulon, North Carolina.

The defect is not dangerous to patients.