BBM
According to The American Polygraph Ins.
Who should NOT take a polygraph test:
Anyone who is being forced to take it.
Any person with a serious heart condition, unless his doctor has given written approval.
A pregnant women, unless her doctor has given written approval. Any person who is determined to be mentally incompetent. Any person who has a respiratory illness or cold. Any person who has nerve damage or paralysis.
Any person who has had a stroke or is an epileptic. Any person who is in pain (i.e., toothache, headache or a recent injury).
http://www.accreditedpolygraphservices.com/polygraph-questions.php