Voice-hearing and other unusual experiences can also occur in response to acute physical illnesses, including high fevers, urinary tract or chest infections, and sepsistA life-threatening reaction to an infection.. Many of these conditions are common in people over the age of 65.

Delirium is a state of confusion that can sometimes occur during hospitalised treatment, particularly when someone is treated in an Intensive Care Unit (ICU). It often involves experiences of hearing voices, seeing visions, paranoia and other unusual beliefs. Delirium can be extremely frightening and can often lead to post-traumatic stress, with some individuals reporting being more traumatised by the experience of delirium than the illness or injury that caused their hospital stay.

Other causes of voice-hearing include poor sleep, withdrawal from some medications, and taking a range of conflicting prescription drugs to manage different health conditions, all of which can become more common as we age.