The TMS Committee of the International Federation of Clinical Neurophysiology suggests that TMS should not be used under these circumstances:

  • The presence of metal anywhere in the head, excluding the mouth. This includes shrapnel, and screws and clips from surgical procedures.

  • TMS also should not be performed in patients with electrodes inside the heart which might provide a low-resistance current path to electrically sensitive tissue.

  • Persons with increased intracranial pressure, as in acute large intracranial infarctions or trauma, are also at increased risk in the event of a seizure, and should not receive TMS.

  • Safety of TMS during pregnancy has not been established, therefore pregnant women are not potential candidates for TMS at this time.

  • Finally, great caution is needed when applying TMS to subjects with a history of seizures, a family history of epilepsy, and patients taking medication that might increase the risk of seizures.