The man's condition improved after he received treatment for his psychosis, his doctors wrote in the report.
"St. John’s wort (Hypericum perforatum) has been known for centuries for its therapeutic properties, and its efficacy as an antidepressant has been confirmed by a growing body of evidence," the doctors who treated the man, at the hospital AUSL Modena in Italy, wrote in their report. But the herb's "availability without prescription, as an over-the-counter medication, raises some concern regarding its clinical management and unsupervised administration to individuals with" mental health risks, they wrote. [7 Ways Depression Differs in Men and Women]
Although there is evidence showing that the herb may reduce depression symptoms in the short term, there is no evidence of its effectiveness when it comes to long-term outcomes, said Dr. Eugene Grudnikoff, a psychiatrist at South Oaks Hospital in Amityville, New York, who was not involved in the new report. There is no evidence showing that using the herb may lead to fewer hospitalizations of patients with depression, fewer suicide attempts or suicides, or better quality of life for people with depression, Grudnikoff told Live Science.
The case in Italy involved a 25-year-old man who was admitted to the hospital after two of his friends, who accompanied him to the hospital, told the doctors that he had been acting strangely in the past few days. The man behaved as if he were under the influence of an illegal drug, the friends said. The doctors examined the patient and observed that he was having speech problems and was experiencing episodes of paranoid thinking and delusions. For example, the man believed that other people could read his mind.
The man also told his doctors he had been feeling weak and had been going through what he called "a period of distress," according to the report, published May 15 in the Journal of Medical Case Reports.
But the man's blood test results were normal, and he did not have any neurological issues. The doctors diagnosed him with a condition called schizophreniform disorder — a type of mental disorder that involves psychosis. They gave him antipsychotic medications to treat his symptoms, and two weeks after his admission, his condition improved and he went home.
Over the next three months, the man visited the local community mental health service as part of his follow-up treatment. During one of these visits, he said that he had experienced a previous psychotic episode, about nine months prior to the psychotic episode for which the authors of the new report had treated him. That earlier episode coincided with the man's abuse of marijuana, the researchers wrote. The man had seen a specialist to treat his symptoms, and that specialist prescribed an antipsychotic for him, but the man refused to take it. However, he stopped using marijuana and felt better, he said.
About three months prior to being admitted to the hospital for his latest psychotic episode, the man had started feeling weak and exhausted, and had severe stomach pain. Over time he began feeling so weary that he quit his job. He eventually saw a doctor, who determined that the man had numerous stomach erosions and an infection of Helicobacter pylori — a type of bacteria known to cause stomach ulcers.
But the man refused to take the medication that the doctor prescribed to treat those symptoms. Instead, he decided to self-medicate with tea made with St. John’s wort. The man said he had been drinking four cups of the tea per day until he was admitted to the hospital for his most recent psychotic episode. [5 Controversial Mental Health Treatments]
It is impossible to determine with certainty whether the tea caused the man's psychotic episode, the doctors wrote. But the herbal tea "could have played a determinant role in the onset" of the man's symptoms, they wrote. That's because previous research has shown that some of its compounds may interact with systems in a person's body that are involved in regulating mood.
Moreover, a few other case reports, including one published in 2004 in the journal Human Psychopharmacology: Clinical & Experimental, have implicated the herb as a potential contributor to psychosis and other psychiatric symptoms.
Originally published on Live Science.
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