A female, 44-years-old, has been on flupenthixol therapy (Fluanxol), 0.5 mg/day since June 1993. S

Fråga: A female, 44-years-old, has been on flupenthixol therapy (Fluanxol), 0.5 mg/day since June 1993. Since then, she suffered frequent episodes of constipation and developed paralytic ileus one month after initiating the therapy. In June 1994, she developed a second episode of ileus and the treatment with flupentixol was discontinued. Additionally, she was treated with citalopram (Cipramil), which was also discontinued. However, the patient continues with moclobemid, 600 mg/day (Aurorix). The patient developed a third episode of ileus in October 1994.

Could these episodes of ileus be an adverse effect of the psychotropic therapy?

Sammanfattning: Paralytic ileus is an infrequent but serious disorder complicating neuroleptic therapy. A careful evaluation is indicated in the constipated psychiatric patient who exhibits vomiting, abdominal pain or abdominal distension since this adverse effect is potentially life threatening. The mechanisms of gastrointestinal motility are complex and not fully understood. It is possible that an individual predisposition may be important for the precipitation of gastrointestinal atony by psychotropic drugs.

Svar: Anticholinergic side effects of psychotropic drugs are well known and have previously been dealt with in Drugline (1-3). They usually consist of dry mouth, blurred vision, constipation and urinary retention. Profound loss of intestinal motility, seen clinically as adynamic, paralytic ileus or megacolon are infrequent. It has been associated several times with phenothiazine therapy, even yielding one fatal outcome (4,5).

Flupenthixol is an antipsychotic drug belonging to thioxanthene class (structurally similar to phenotiazines) which, unlike chlorpromazine, claims to have CNS activating properties; therefore, it is not often used in excited or manic patients. Extrapyramidal disorders are more frequent with flupenthixol than with chlorpromazine, but at doses with equipotent antipsychotic activity, the low potency agents (ie chlorpromazine) are more prone to cause sedation and antimuscarinic or alpha-adrenergic-blocking effects than the high potency agents (ie flupentixol) (6). However, a case report of a patient with ileus complicating haloperidol therapy (a high potency agent) also illustrates the potential risk of ileus in this class of drugs (7).

Woodring (8) has recently reported a case of esophageal atony and massive dilatation that occurred as an anticholinergic side effect of thiothixene in association to benztropine mesylate. The esophageal dilatation disappeared after the drugs were discontinued and reoccurred when they were readministered.

There is also a report on the neuroleptic malignant syndrome with marked abdominal distension within twenty four hours of initiating the treatment (chlorpromazine 50 mg three times a day and flupenthixol 20 mg intramuscular) in a 36-year-old woman (9). The patient had a similar episode two years before with development of a febrile illness and an acute distended abdomen two days after an injection of flupenthixol (9).

We recommend that this case should be reported to the Regional Centre of the Swedish Adverse Drug Reactions Advisory Committee (SADRAC). 1 Drugline nr 01286 (year 1978) (enclosed) 2 Drugline nr 03355 (year 1982) (enclosed) 3 Drugline nr 03586 (year 1983) (enclosed) 4 Evans DL, Rogers JF, Peiper SC: Intestinal dilatation associated with phenothiazine therapy: A case report and literature review. Am J Psychiatry 1979; 136: 970-972 5 Kemeny MM, Martin EC, Lane FC, Stillman RM: Abdominal distention and aortic obstruction associated with phenothiazines. JAMA 1980; 243: 683-684 6 Baldessarini RJ: Drugs and the treatment of psychiatric disorders. In: Goodman A, Rall TW, Noes AS, Taylor P (eds). New York, Pergamon Press 1990; 383-435 7 Maltbie AA, Varia IG, Thomas NU: Ileus complicating haloperidol therapy. Psychosomatics 1981; 22: 158-159 8 Woodring JH, Martin CA, Keefer B: Esophageal atony and dilatation as a side effect of thiothixene and benztropine. Hosp Community Psychiatry 1993; 44: 686-688 9 Lo TCN, Unwin MR, Dymock IW: Neuroleptic malignant syndrome: another medical cause of acute abdomen. Postgrad Med J 1989; 65: 653-655