title: Risperidone-Induced Adverse Drug Reactions and Role ofDRD2(-141 C Ins/Del) and5HTR2C(-759 C>T) Genetic Polymorphisms in Patients with Schizophrenia.
abstract: OBJECTIVE
  To determine the adverse drug reaction (ADR) profile of risperidone and their association with dopamine (DRD2- 141 C Ins/Del/rs1799732) and serotonin receptor (5HTR2C-759 C>T/rs3813929) gene polymorphisms in patients with schizophrenia.
  
  
  METHODS
  The study was conducted among 289 patients who were diagnosed with schizophrenia and were on treatment with risperidone (4-8 mg/day)-based therapy for a minimum of 4 weeks. Genotyping was carried by real-time quantitative polymerase chain reaction. All the patients were observed for the occurrences of ADRs during the study. Changes in prolactin levels and body weight were analyzed for a subgroup of 102 and 97 patients, respectively.
  
  
  RESULTS
  Risperidone-induced extrapyramidal symptoms (EPSs) were seen in 36.7% of patients. Among them, tremors were the most common symptom 31.8%. Risperidone-induced hyperprolactinemia and weight gain were seen in 87.2% and 53.6% in subgroup patients. Adverse effects such as sedation, gastrointestinal effects, and amenorrhea were seen in 9.7% (28/289), 5.1% (15/289), and 6.1% (7/114), respectively. Occurrence ofDRD2- 141 Ins/Del and Del/Del polymorphisms were significantly associated with increased prolactin levels in response to risperidone (odds ratio [OR] = 10.45; 95% confidence interval = 1.29-84.89,P= 0.004). No such association was observed with5HTR2C(-759 C>T) polymorphism. Weight gain and EPS were not associated with the above genetic polymorphisms.
  
  
  CONCLUSIONS
  Hyperprolactinemia, weight gain, and EPSs (>36.7%) were common adverse effects of risperidone.DRD2- 141C Ins/Del and Del/Del polymorphisms were significantly associated with increased prolactin levels (OR = 10.45) in response to risperidone.
authors.affiliation: Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Charanraj Goud
authors.initials: CG
authors.lastname: Alladi
authors.affiliation: Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Anbarasan
authors.initials: A
authors.lastname: Mohan
authors.affiliation: Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Deepak Gopal
authors.initials: DG
authors.lastname: Shewade
authors.affiliation: Department of Psychiatry, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Ravi Philip
authors.initials: RP
authors.lastname: Rajkumar
authors.affiliation: Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Surendiran
authors.initials: S
authors.lastname: Adithan
authors.affiliation: Department of Psychiatry, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
authors.forename: Karthick
authors.initials: K
authors.lastname: Subramanian
keywords: Adverse drug reactions; hyperprolactinemia; risperidone; rs1799732; rs3813929; schizophrenia