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Antiepileptic drugs and bone disease

Alison M Pack, MD
Elizabeth Shane, MD
Section Editors
Timothy A Pedley, MD
Marc K Drezner, MD
Deputy Editor
Jean E Mulder, MD


Epilepsy is a chronic condition that affects over two million people in the United States, approximately 1 percent of the population [1]. Antiepileptic drugs (AEDs) remain the mainstay of treatment for epilepsy. In addition, these agents now have numerous other indications, including the treatment of migraine headaches, bipolar disorder, and chronic pain.

Both epilepsy and AEDs are associated with adverse effects on bone health. Persons with epilepsy treated with AEDs have increased rates of bone loss and abnormalities in bone and mineral metabolism [2,3]. These adverse effects may contribute to an increased risk of fracture [4-7].

This topic will review the association between AEDs and disorders of bone and mineral metabolism, including osteomalacia/rickets and osteoporosis or low bone mass. In addition, the screening, treatment, and prevention of AED-related bone disease will be discussed.

The management of epilepsy and the pharmacology of AEDs are discussed elsewhere. (See "Overview of the management of epilepsy in adults" and "Initial treatment of epilepsy in adults" and "Antiseizure drugs: Mechanism of action, pharmacology, and adverse effects".)


The first reports linking AED therapy to skeletal disease were published in the late 1960s [8]. Affected patients had florid bone disease with clinical, biochemical, and histologic abnormalities consistent with rickets and osteomalacia. However, these early reports included mostly institutionalized patients.

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Literature review current through: Nov 2017. | This topic last updated: Jan 09, 2017.
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