Urinary retention Associated With Amisulpride
Aggarwal, Jain & Jain
Urinary retention is a painful side effect associated with antipsychotic drugs. Amisulpride is a second generation antipsychotic medication used in the management of psychosis and dysthymia along with depression. We wish to report a rare side effect of urinary retention associated with amisulpride therapy.
Key Words: Urinary retention, Amisulpride
Amisulpride, a substituted benzamide derivative, is another second-generation atypical antipsychotic medication. It is a standard treatment in dysthymia as well as in psychosis. Amisulpride is efficacious, effective and well tolerated in positive symptoms of schizophrenia: there is extensive evidence that it treats negative symptoms when given in low doses, although relative lack of EPS and an antidepressant effect may contribute.1 It is generally well tolerated with adverse effects that have been reported include insomnia, anxiety, agitation, drowsiness, gastrointestinal disorders, dry mouth, and Hyperprolactinemia.2
Although urinary retention has been reported to occur with other antipsychotics, we could not find any report of urinary retention associated with amisulpride. In contrast, we found a case of amisulpride induced urinary incontinence associated with amisulpride.3 We wish to report a case that developed urinary retention while on amisulpride therapy.
Mr A, 26 years old Hindu male was suffering from presented to us with 1 year history of suspiciousness, reporting hearing voices not heard by others, decreased social interaction, anhedonia, decreased self care and socio occupational dysfunction. His past, family and personal history were non significant. Mental status examination revealed rapport not established, fearful affect, delusions of reference and persecution, third person auditory hallucinations, impaired abstraction and insight grade I/V. He had no significant medical history. He was diagnosed as a case of Paranoid schizophrenia according to DSM IV TR. He was started on risperidone up to 6 mg per day without any response. Subsequently, he was started on amisulpride 100 mg per day increased to 800 mg over period of next 3 weeks. The patient gradually started showing improvement in her symptoms and she tolerated the drug well. However, after about 5 weeks of amisulpride therapy, the patient developed difficulty in urination and had hesitancy. He would have to make an effort to pass urine. Subsequently, within next few hours, he developed complete urinary retention along with severe abdominal pain which increased while he tried to micturate. He was taken to emergency and catheterization was done. His USG Abdomen and pelvis was within normal limits. Physical examination and other relevant laboratory tests were normal .No local pathology was identified. The dose of amisulpride was decreased to 400 mg per day. The patient has shown improvement in his psychotic symptoms and has been stable for the last 6 months without reporting any urinary complaints.
The Naranjo adverse drug reaction probability scale used in our case indicates a highly probable relationship between urinary retention and amisulpride therapy in this patient.4 The appearance of urinary retention at higher dose and disappearance with subsequent dose reduction suggests this to be a dose related phenomena. In contrast to other typical antipsychotics where cholinergic blockade is proposed as the mechanism, it is difficult to speculate the mechanism for amisulpride induced urinary retention as it has no affinity for cholinergic receptors. Amisulpride is specific for its action on dopamine D2 and D3 receptors in the limbic rather than striatal structures.2 It has been reported that at higher doses (>10mg/kg) amisulpride acts as a dopamine receptor blockade and in low doses (<10mg/kg), amisulpride preferentially blocks presynaptic D2/D3 receptors, resulting in enhanced dopamine transmission2.
We can only speculate at present the role of dopaminergic system in causing this side effect. Central acute dopamine-2 (D2) receptor stimulation has been associated with a reduction of bladder capacity and detrusor overactivity5, suggesting that acute D2 blockade caused by higher dose of amisulpride may be a factor in urinary hesitancy and retention. Subsequently, lowering the dose might be beneficial for the same.
Our patient did not have any risk factor for urinary retention like prostrate hypertrophy or old age; still he developed this side effect. Our report suggests that one should be cautious while using this drug and patients should be explained about this rare but possible side effect. Special care should be taken in elderly and other population prone to anticholinergic side effects. Further studies are required to characterize the urinary problems associated with amisulpride therapy and also to characterize the patients at risk for these troublesome side effects.
1. Dr Ashish Aggarwal, MD, Senior Resident, Department of Psychiatry, Indira Gandhi Medical College, Shimla, Himachal Pradesh
2. Dr Manish Jain, MD, Senior Resident, Department of Psychiatry, Dr RML Hospital, New Delhi
3. Dr Pramit Jain, DNB Resident, IMHH, Agra
1. Mortimer AM. Update on the management of symptoms in schizophrenia: focus on amisulpride. Neuropsychiatric Disease and Treatment. 2009; 5: 267–277
2. McKeage K, Plosker L. Amisulpride: A review of its use in the management of schizophrenia. CNS Drugs 2004; 18(13):933-956
3. Mendhekar D, Lohia D. Urinary incontinence associated with amisulpride. World J Biol Psychiatry. 2008; 7:1-2.
4. Naranjo CA, Busto U, Sellers EM, Sandor P, Ruiz I, Roberts EA, et al. 1981. A method for estimating the probability of adverse drug reaction. Clin Pharmacol Ther 30 (2): 239-45
5. Brusa L, Petta F, Pisani A, et al. Central acute D2 stimulation worsens bladder function in patients with parkinson’s disease. J Urol. 2006;175(1):202-206
Copyright Priory Lodge Education Limited 2009
First Published September 2009