Psychosis drug-induced

The final area specifically considered here which poses major problems in diagnosis and management is that of drug-induced psychosis, and a helpful editorial in the British Journal of Psychiatry was critical of the understanding of this concept (Poole Brabbins 1996). The authors point out that although drug-induced psychosis is routinely included in the... 

Poole R Brabbins C (1996). Drug induced psychosis. British Journal of Psychiatry, 168, 135-8... 

Another long-term health effect of psychedelic use is persistent or drug-induced psychosis, in which former users can fall into a long-lasting psychotic-like state. They can appear severely depressed, have mood swings, and have hallucinations and visual disturbances. Like HPPD, persistent psychosis can last for years. Often it occurs in people who have no previous history of psychological problems. 

While there is no formal treatment for HPPD and drug-induced psychosis, those who have trouble coping with the symptoms are often treated with antidepressants to help reduce the symptoms. Former users who experience flashbacks are often fearful and confused by the inexplicable hallucinations, and it is reported that they think they may have suffered brain damage or are going insane. Psychotherapy may help them cope. 

Q7 Other conditions which may present similar symptoms include drug-induced psychosis such as one brought on by lysergic acid diethylamide, or LSD, or amphetamine, personality disorder or affective psychosis. In older patients dementia may present with schizophrenia-like symptoms, but these patients usually have significant memory deficits, which do not occur in schizophrenia. 

The findings are entirely compatible with prerenal azotemia associated with diminished fluid intake during a drug-induced psychosis (81). 

Clozapine has been used to treat psychosis related to Parkinson s disease (SEDA-22,57) (78). In a randomized, double-blind, placebo-controlled trial of low doses of clozapine (6.25-50 mg/day) in 60 patients (mean age 72 years) with idiopathic Parkinson s disease and drug-induced psychosis, the patients in the clozapine group had significantly more improvement after 14 months than those in the placebo group in all measures used to determine the severity of psychosis (80). Clozapine improved tremor and had no deleterious effect on the severity of parkinsonism, but in one patient it was withdrawn because of leukopenia. 

Poliak P, Tison F, Rascol O, Destee A, Pere JJ, Senard JM, Durif F, Bourdeix I. Clozapine in drug induced psychosis in Parkinson s disease a randomised, placebo controlled study with open follow up. J Neurol Neurosurg Psychiatry 2004 75 689-95. 

Friedman J, Lannon M, Cornelia C, Factor S, Kurlan R, Richard I. Low-dose clozapine for the treatment of drug-induced psychosis in Parkinson s disease. New Engl J Med 1999 340 757-63. 

Whether treatment with olanzapine is useful in psychotic symptoms in patients with Parkinson s disease is unclear (SEDA-23, 66). Nine patients of twelve with drug-induced psychosis in Parkinson s disease had worsening of motor function while taking olanzapine (2.5 mg/ day and increased in 2.5 mg increments as needed) this worsening was considered dramatic in six of these patients, and only one was still taking olanzapine at the time of the analysis (12 months) (116). In addition, two elderly patients, one with and one without pre-existing parkinsonism, had marked rigidity induced by olanzapine 5 mg/day (117). 

Evans M, Perera PW, Donoghue J. Drug induced psychosis with doxazosin. BMJ 1997 314(7098) 1869. 

Williams H, Meagher D, Galligan P. MDMA. ( Ecstasy ) a case of possible drug-induced psychosis. Ir J Med Sci 1993 162(2) 43. ... 

TABLE 57—6. Stepwise Approach to Drug-Induced Psychosis in Parkinson s Disease... 

---