Hallucinations are the perception of something that doesn’t exist. They can be auditory (heard), visual (seen), tactile (felt) or olfactory (smelled).
There are many causes for hallucinations, the most common being recreational drugs and dementia or delirium, but they can also be caused by high fevers or certain illnesses. Some people who have survived serious, life-threatening illnesses, like septic shock, have reported having very vivid hallucinations while they were in the intensive care unit (ICU).
Hallucinations are often very disturbing and the memories can be long lasting, but the hallucinations aren’t understood. A few researchers have been looking at how often hallucinations occur among critically ill patients. One study looked at 289 critically ill patients who had been in an ICU for 24 hours or longer and been sedated and intubated (placed on a ventilator). The researchers found that 9.3% of the patient had nightmares and 6.6% said that they had experienced hallucinations. For some people, the hallucinations continue, even after they are no longer in the ICU environment. Another study found that after leaving the critical care area, some patients experienced, “amnesia, continued hallucinations or flashbacks, anxiety, depression, and dreams and nightmares.”
There are theories as to why patients may experience hallucinations, but there are no clear explanations yet. Patients in an ICU are not only fighting a very serious illness, they don’t get a lot of rest. Nursing care is necessary and frequent, and lights are on in the hallways. Even when lights are dimmed, they may keep patients from sleeping. There is a lot of noise that comes from nurses moving about and talking to patients and one another, machines operating, and alarms beeping. The constant stimulation often causes sleep deprivation. It is known that serious lack of sleep can cause psychological distress.
If you experienced hallucinations while hospitalized for sepsis or septic shock, you are not alone. Some of the people who have shared their stories in our Faces of Sepsis section mention that they saw or heard things that they knew weren’t there.
If you are having a hard time dealing with the after effects of sepsis, which can include bad dreams, hallucinations, even memories of the hallucinations, this could be part of post-traumatic stress disorder, or PTSD. There are counselors and therapists who specialize in treating PTSD. They may use a variety of methods, including cognitive therapy, tapping techniques, or eye movement desensitization reprocessing (EMDR). Counseling can be an important component of full recovery from sepsis.
The information here is also available as a Sepsis Information Guide, which is a downloadable format for easier printing.
Would you like to share your story about sepsis or read about others who have had sepsis? Please visit Faces of Sepsis, where you will find hundreds of stories from survivors and tributes to those who died from sepsis.
Updated November 20, 2019.