It depends on the underlying cause of the hallucinations.
Hallucinations are by themselves simply a symptom; specifically a "psychotic symptom." The question you're asking, unfortunately, pre-supposes that all psychotic symptoms derive from the same root cause.
Hallucinations, like any psychotic feature, might be brought on by organic processes within the brain (ie dementia), neuro-psychiatric processes (ie Schizophrenia), drug intoxication, poisoning, fever, etc. You need a skilled clinician to analyze the accompanying symptoms to tell which category the "problem" falls under and what the specific illness or condition is.
hallucinating...
Go to an mental Institute or you take an aspirin and call your doctor in the morning
Hallucinating Foucault was created in 1996.
Hallucinating Anxiety was created in 1990-11.
Hallucinating Foucault has 178 pages.
The correct spelling is hallucinating.
no
The ISBN of Hallucinating Foucault is 0-330-35177-X.
Hallucinating.
You are hallucinating.
its not, you are hallucinating
Hallucinating!