A Case of Stuttering During Treatment with Levomepromazine

Stuttering is a disturbance in the normal fluency and time patterning of speech, characterized by sound and syllable repetitions, sound prolongations and broken words. Acquired stuttering that begins in adulthood is rather unusual. It might be associated with different neurological disorders, like traumatic brain injuries, strokes, or extrapyramidal diseases. Rarely, it has been also reported as a side effect of different psychopharmacologic drugs, including selective serotonin reuptake inhibitors, tricyclic antidepressants, phenothiazines, olanzapine, clozapine¹ and risperidone.² To our best knowledge, there is only one article with descriptions of two patients who developed stuttering as a dose-dependent side effect of treatment with three different phenothiazine antipsychotics (chlorpromazine, trifluoperazine, and fluphenazine).³ However, a case of stuttering associated with the use of levomepromazine (also known as mepromazine or methotrimeprazine) has so far not been reported. Levomepromazine is a low-potency aliphatic phenothiazine antipsychotic characterized by strong sedative abilities⁴ and 5-HT2A:D2 affinity ratio 5:1.⁵ We present a case in which levomepromazine was implicated as a potential cause of stuttering.