Multicenter Observational/Exploratory Study Addressed to the Evaluation of the Effectiveness and Safety of Pharmacological Therapy in Opioid-Dependent Patients in Maintenance Therapy in Southern Italy.

A multicenter-observational study was performed to assess the effectiveness of rac-methadone, levomethadone, and buprenorphine in opioid-dependent patients in polytherapy in Southern Italy. The primary endpoint was the reduction of urinary positivity to the substances and the maintaining doses. Patients (N = 266, age = 44.80 ± 5.65, male = 79.70%, female = 20.30%) have been recruited. At recruitment, 75% of them were on treatment with rac-methadone, levomethadone, and buprenorphine/naloxone. The patients were grouped into three clusters. The levomethadone patients of Cluster A (N patients = 211), after 180 days, showed stability in urinary methadone positivity, with a marked decrease in heroin -53 ± 4%, cannabinol's -48 ± 2%, and cocaine -37 ± 6% positivity, with no differences between treatments. A lower QTcF value of 426 ± 8.4 ms was recorded in the levomethadone patients (delta = -19 ms) vs. rac-methadone, at significantly lower doses of levomethadone (-34%, -50.2% in males) (p < 0.05). The Cluster B data were collected from 37 patients, with a high prevalence of comorbidity infections (HIV/HCV/HPV), monitored for 21 months during COVID-19. High doses of levomethadone (58.33 ± 31.58 mg/day) were needed to stabilize those that were negative for opioids and cannabinoids, in contrast to the rac-methadone and buprenorphine/naloxone patients that showed positive toxicology. Eighteen patients of the Cluster C in double diagnosis (major depressive 38.90%, bipolar 27.78%, and schizophrenia 16.67%) were stabilized with high doses of racemate 97.5 ± 8 mg/day, 51.8 ± 5 mg/day of levomethadone (-46.8% vs. rac-methadone; -71% in men), and 2.5 ± 1 mg/day of buprenorphine/naloxone. Three patients in remission were treated with tapering doses of levomethadone. Significantly reduced QTcF values were recorded with levomethadone (delta -32 ms vs. rac-methadone) in the bipolar patients, as well as the schizophrenia patients in remission (delta -45.19 ms vs. rac-methadone). Our patients were safely stabilized. Levomethadone, compared to the racemate, contributes to reducing the illicit use, especially of opioids and cannabinoids at significantly lower doses with cardiovascular safety, which, in bipolar patients, is clinically significant.

Genomic and Personalized Medicine Approaches for Substance Use Disorders (SUDs) Looking at Genome-Wide Association Studies.

Drug addiction, or substance use disorder (SUD), is a chronic, relapsing disorder in which compulsive drug-seeking and drug-taking behaviour persist despite serious negative consequences. Drug abuse represents a problem that deserves great attention from a social point of view, and focuses on the importance of genetic studies to help in understanding the genetic basis of addiction and its medical treatment. Despite the complexity of drug addiction disorders, and the high number of environmental variables playing a role in the onset, recurrence, and duration of the symptoms, several studies have highlighted the non-negligible role of genetics, as demonstrated by heritability and genome-wide association studies. A correlation between the relative risk of addiction to specific substances and heritability has been recently observed, suggesting that neurobiological mechanisms may be, at least in part, inherited. All these observations point towards a scenario where the core neurobiological factors of addiction, involving the reward system, impulsivity, compulsivity, stress, and anxiety response, are transmitted, and therefore, genes and mutations underlying their variation might be detected. In the last few years, the development of new and more efficient sequencing technologies has paved the way for large-scale studies in searching for genetic and epigenetic factors affecting drug addiction disorders and their treatments. These studies have been crucial to pinpoint single nucleotide polymorphisms (SNPs) in genes that affect the reaction to medical treatments. This is critically important to identify pharmacogenomic approaches for substance use disorder, such as OPRM1 SNPs and methadone required doses for maintenance treatment (MMT). Nevertheless, despite the promising results obtained by genome-wide association and pharmacogenomic studies, specific studies related to population genetics diversity are lacking, undermining the overall applicability of the preliminary findings, and thus potentially affecting the portability and the accuracy of the genetic studies. In this review, focusing on cannabis, cocaine and heroin use, we report the state-of-the-art genomics and pharmacogenomics of SUDs, and the possible future perspectives related to medical treatment response in people that ask for assistance in solving drug-related problems.

Lamotrigine positively affects the development of psychiatric comorbidity in epileptic animals, while psychiatric comorbidity aggravates seizures.

Several clinical and preclinical studies have focused on the relationship between epilepsy and psychological disturbances. Although behavior in some experimental models of epilepsy has been studied, only few of them can be considered as models of epilepsy and mood disorder comorbidity. Since several models of epilepsy or psychiatric disorders are already available, we wondered whether a mixture of the two could experimentally represent a valid alternative to study such comorbidity. Here, we present a possible experimental protocol to study drug effects and physiopathogenesis of psychiatric comorbidity in epileptic animals. Pentylentetrazol-kindled animals were subjected to the chronic mild stress (CMS) procedure; furthermore, we tested the effects of chronic lamotrigine treatment on the development of comorbidity. We found that epileptic-depressed animals showed more pronounced behavioral alterations in comparison to other mice groups, indicating that kindled animals develop more pronounced CMS-induced behavioral alterations than nonepileptic mice; lamotrigine was able to prevent the development of comorbidities such as anxiety, depression-like behavior, and memory impairment.

Pharmacovigilance and drug safety 2011 in Calabria (Italy): Adverse events analysis.

BACKGROUND: Pharmacovigilance assesses the safety profile of drugs. Its main aim is the increase of spontaneous reporting of adverse drug reactions (ADRs). The Italian Drug Agency (AIFA; Agenzia Italiana del Farmaco) is financing several projects to the aim of increasing reporting, and in Calabria a Pharmacovigilance Information Centre has been created. MATERIALS AND METHODS: We analyzed the AIFA database relatively to Calabria in the year 2011 and we have analyzed ADRs using descriptive statistics. We have also collected a questionnaire-based interview in order to describe the background knowledge in the field. RESULTS: Regarding the number of AIFA reported ADRs from Calabria, a 38% increase (138 vs. 100) in comparison to 2010 was evidenced. Hospital Doctors represent the main source of signaling (71.7 %). Ketoprofene and the combination amoxicillin/clavulanic acid represent the most frequently reported drugs causing ADRs. Our questionnaires indicated that despite the health professionals have met at least once an ADR only a small percentage of them was reported to the authorities (37%). There is a very good knowledge of the ADR concept and reporting system (90% of interviewed distinguish an ADR and knows how to report it), and there is a strong interest in participating to training courses in the field (95% are interested). CONCLUSIONS: Despite Calabria has had a positive increase in the number of reported ADRs, the total number is very low and the pharmacovigilance culture is far from being achieved in this region.

Effects of early long-term treatment with antiepileptic drugs on development of seizures and depressive-like behavior in a rat genetic absence epilepsy model.

PURPOSE: Depression is most commonly associated with epilepsy. Recent reports have suggested a putative relationship between seizure development and onset of depressive behavior, whereas others proposed that two clinical entities might represent different neuropathologic aspects of the same neurologic disorder. The WAG/Rij rat absence epilepsy model has also been proposed as a suitable model to test antidepressant drugs. We previously reported on a long-term study of two antiepileptic drugs (AEDs) to assess their protective role in absence epileptogenesis. Here, we examined the effects of long-term treatment with several AEDs on absence seizure development and onset of depressive-like behavior in WAG/Rij rats at different ages, using a forced swimming test (FST). METHODS: Animals were divided into one untreated control group and four test groups, given ethosuximide, levetiracetam, zonisamide, or carbamazepine. Electroencephalography (EEG) readings were recorded at 6.5 months of age. KEY FINDINGS: Ethosuximide-treated animals showed significant reductions in recorded spike-wave discharges (SWDs), and FST immobility time (IT) compared with untreated same age controls. However, zonisamide- and carbamazepine-treated animals had IT values similar to those of controls, but only zonisamide significantly decreased absence seizure development. Carbamazepine increased SWD incidence. Levetiracetam also protected against seizure development, while augmenting IT, suggesting a prodepressive effect. SIGNIFICANCE: Although treatment with ethosuximide, levetiracetam, or zonisamide reduced appearance of SWDs in WAG/Rij rats, this was not generally linked to a reduced onset of depressive characteristics, as assessed by FST. Therefore, expression of depressive-like behavior seems unrelated to seizure control in this model. Some possible alternative explanations for the observed data are discussed.

Preclinical activity profile of α-lactoalbumin, a whey protein rich in tryptophan, in rodent models of seizures and epilepsy.

PURPOSE: To evaluate the potential anticonvulsant activity of α-lactalbumin (ALAC), a whey protein rich in tryptophan (TRP) relative to other large neutral amino acids (LNAAs), in rodent models of seizures and epilepsy. METHODS: The effects of ALAC administered per os were evaluated by standard protocols against audiogenic seizures in Genetic Epilepsy Prone Rats (GEPR-9 rats), maximal electroshock (MES)-induced seizures in rats, pilocarpine-induced seizures in mice, spontaneous chronic seizures in mice exposed to pilocarpine-induced status epilepticus (SE), and absence seizures in WAG/Rij rats. In some models, carbamazepine (CBZ) was included as an active control. Plasma TRP/LNAAs ratios were measured by GC-MS. RESULTS: Single doses of ALAC up to 500 or 6000 mg/kg were devoid of anticonvulsant activity in all models tested. Conversely, 5- and 12-day treatment with ALAC (250-1000 mg/kg/day) in GEPR rats reduced dose-dependently seizure scores and prolonged latency to clonus onset, with full persistence of the effect for up to 12h. ALAC (125-500 mg/kg/day for 15 days) protected against seizures induced by 250 mg/kg pilocarpine, but was less effective against higher pilocarpine doses. Similarly to CBZ, ALAC (125-500 mg/kg/day for 15 days) was also effective against spontaneous seizures in the post-pilocarpine SE model. ALAC (up to 6000 mg/kg/day for 12 days) did not prevent MES-induced seizures, although it reduced the duration of tonic extension at doses between 250 and 1000 mg/kg/day. Absence seizures in WAG/Rij rats were not significantly affected by ALAC. Plasma TRP/LNAAS ratios increased 2- to 3-fold after dosing with ALAC (250 mg/kg/day) for 7 and 14 days, respectively. CONCLUSIONS: ALAC exerts significant protective activity against seizures in animal models, the effect being especially prominent against audiogenic seizures in GEPR-9 rats, seizures induced by low-dose pilocarpine in mice, and spontaneous seizures in mice exposed to pilocarpine-induced SE. This action is likely to be mediated by increased availability of TRP in the brain, with a consequent increase in 5-HT mediated transmission.

Patterns of prescription of antiepileptic drugs in patients with refractory epilepsy at tertiary referral centres in Italy.

PURPOSE: To evaluate the pattern of prescription of antiepileptic drugs (AEDs) and other medications in a representative population of patients with refractory epilepsy attending tertiary referral centres in Italy. METHODS: Descriptive analysis of data obtained at baseline from 933 adults and 191 children with refractory epilepsy enrolled consecutively in an observational study at 11 tertiary referral centres in Italy. Multivariate logistic regression analysis was used to assess predictors of utilization of the most commonly prescribed AEDs. RESULTS: Polytherapy was used in 79% of adults and 75% of children, with over one-third of adults and children being prescribed ≥3 AEDs. In adults, the most commonly used AEDs were levetiracetam (35%), carbamazepine (34%) and lamotrigine (30%). In children, valproic acid was by far the most commonly used AED (46%), followed by carbamazepine (27%), topiramate (21%), and phenobarbital (20%). The most common AED in partial epilepsy was carbamazepine (331 out of 893 patients, 37%), followed by levetiracetam (33%) and lamotrigine (26%). In generalized or undetermined epilepsies, the AEDs most commonly used were valproic acid (139 out of 223 patients, 62%), lamotrigine (33%) and levetiracetam (28%). Second generation AEDs were prescribed in 81% of adults and 54% of children. Comedications used for indications other than epilepsy were used by 32% of adults and 17% of children. CONCLUSIONS: Prescription patterns were consistent with current evidence about the spectrum of efficacy of individual AEDs in different epilepsy syndromes. The high prevalence of polytherapy, including combinations of three or more AEDs, is a cause for concern.

Laxative-induced rhabdomyolysis.

The present study describes a case of laxative-induced rhabdomyolysis in an elderly patient. An 87-year-old woman was hospitalized for the onset of confusion, tremors, an inability to walk, and a fever that she had been experiencing for 36 hours. She often took high dosages of lactulose and sorbitol syrup as a laxative (about 70 g/day). During her physical examination, the patient was confused, drowsy, and she presented hyposthenia in her upper and lower limbs, symmetric and diffuse moderate hyporeflexia, and her temperature was 37.8 degrees C. Laboratory tests revealed severe hyponatremia with hypokalemia, hypocalcemia, hypochloremia, and metabolic alkalosis. Moreover, rhabdomyolysis markers were found. The correction of hydroelectrolytic imbalances with saline, potassium and sodium chlorure, calcium gluconate was the first treatment. During her hospitalization the patient presented acute delirium, treated with haloperidol and prometazine chloridrate intramuscularly. She was discharged 12 days later, after resolution of symptoms, and normalized laboratory tests. Over-the-counter drugs such as laxatives are usually not considered dangerous; on the other hand, they may cause serum electrolytic imbalance and rhabdomyolysis. A careful monitoring of all the drugs taken by the elderly is one of the most important duties of a physician since drug interactions and their secondary effects may be fatal.

Comparison of the antiepileptogenic effects of an early long-term treatment with ethosuximide or levetiracetam in a genetic animal model of absence epilepsy.

PURPOSE: Epilepsy is a heterogeneous syndrome characterized by recurrent, spontaneous seizures; continuous medication is, therefore, necessary, even after the seizures have long been suppressed with antiepileptic drug (AED) treatments. The most disturbing issue is the inability of AEDs to provide a persistent cure, because these compounds generally suppress the occurrence of epileptic seizures without necessarily having antiepileptogenic properties. The aim of our experiments was to determine, in the WAG/Rij model of absence epilepsy, if early long-term treatment with some established antiabsence drugs might prevent the development of seizures, and whether such an effect could be sustained. METHODS: WAG/Rij rats were treated for ∼3.5 months (starting at 1.5 months of age, before seizure onset) with either ethosuximide (ETH; drug of choice for absence epilepsy) or levetiracetam (LEV; a broad-spectrum AED with antiabsence and antiepileptogenic properties). RESULTS: We have demonstrated that both drugs are able to reduce the development of absence seizures, exhibiting antiepileptogenic effects in this specific animal model. DISCUSSION: These findings suggest that absence epilepsy in this strain of rats very likely follows an epileptogenic process during life and that early therapeutic intervention is possible, thereby opening a new area of research for absence epilepsy and AED treatment strategies.

Sertraline-induced rhabdomyolysis in an elderly patient with dementia and comorbidities.

OBJECTIVE: To describe a case of sertraline-induced rhabdomyolysis in an elderly patient with dementia and comorbidities. CASE SUMMARY: A 71-year-old woman visited a psychiatrist in September 2007 for her depressed mood. Her medical history included vascular dementia accompanied by depression, arterial hypertension, and heart failure, as well as cardiac pacemaker implantation several years earlier for severe bradyarrythmia. She had begun taking amisulpride 50 mg/day and diazepam 2 mg at bedtime 6 months prior to the psychiatrist appointment, with poor relief of her depressed mood. Her drug therapy also included nicergoline 30 mg/day, amlodipine 5 mg/day, aspirin 100 mg/day, candesartan 16 mg/day, and atenolol 25 mg/day. At this psychiatrist visit, sertraline 50 mg/day was added for her depression, and was continued after a geriatrician visit in October. Her mood improved significantly. On December 18, 2007, she was admitted to the cardiology unit to undergo a pacemaker replacement. Laboratory tests revealed creatine kinase (CK) 7952 IU/L, lactate dehydrogenase 1021 IU/L, myoglobin 2322 U/L, and aspartate aminotransferase 362 IU/L, resulting in a diagnosis of iatrogenic rhabdomyolysis. Amisulpride and sertraline were discontinued. On December 24, serum CK was 839 IU/L and myoglobin was 91 U/L and the patient was discharged. On January 22, laboratory tests showed normal values of CK, CK-MB, and myoglobin. Sertraline 50 mg/day was again prescribed for the patient's persistent depressed mood. Fifteen days later, blood tests showed CK 1327 IU/L and myoglobin 324 U/L; therefore, the drug was discontinued. CK and myoglobin levels normalized a week later. On April 2, escitalopram was started. At time of writing, there was no evidence of any increase in CK, myoglobin, or other markers of rhabdomyolysis. DISCUSSION: The Naranjo probability scale indicated a probable relationship between sertraline treatment and the onset of rhabdomyolysis. No relationship between amisulpride and rhabdomyolysis was found. Furthermore, rechallenge with sertraline caused CK and myoglobin to again increase, which was reversed following a discontinuation of sertraline. The patient's other comorbidities and medications have not been suggested as possible interactions with sertraline that can cause rhabdomyolysis. Genetic defects of sertraline demethylation and/or Pglycoprotein binding or concurrent circumstances may explain the onset of rhabdomyolysis in this particular patient. CONCLUSIONS: This patient's rhabdomyolysis was probably induced by sertraline therapy.

The safety of clozapine in the elderly.

BACKGROUND: Clozapine was the first atypical 'broad spectrum' antipsychotic drug to be marketed and the first agent approved for the treatment of schizophrenia refractory to other medications. It is also effective for the treatment of aggressive behaviour in schizophrenic and demented patients and in the management of psychosis and aggression in Parkinson's disease and Lewy body dementia. OBJECTIVE: The aim of this review is to study the safety of clozapine for use in elderly patients. METHODS: An extensive Medline search was made. Some studies that were referenced in reports from our pharmacovigilance centre and from regulatory agencies such as the FDA, EMEA and WHO were included. CONCLUSIONS: Clozapine treatment in the elderly requires a careful geriatric assessment. However, its use is strongly limited by the possibility of onset of severe adverse effects such as potentially fatal agranulocytosis, myocarditis and others such as seizures, weight gain and metabolic adverse effects.

Effects of ethanol on the development of genetically determined epilepsies in rats.

In the present study, we provide evidences for a differential effect of perinatal alcohol exposure with a direct correlation to the genetic background on the development of seizures. Ethanol (EtOH) is a widely used psychoactive substance that exerts its action by affecting multiple targets in the central nervous system. EtOH is known to interact with almost all identified neurotransmitters although its effects on excitatory and inhibitory amino acid neurotransmissions are considered to be particularly important in the mediation of its behavioural effects. Prenatal exposure to alcohol is associated with a wide variety of offspring's abnormalities which lead to the so called foetal alcohol syndrome (FAS), which is also related to a higher susceptibility to convulsions. In our study, a rat strain of convulsive epilepsy, the GEPRs rats, displayed an increase of seizure susceptibility after foetal exposure to this teratogenic drug, while a non-convulsive rat strain of absence epilepsy, the WAG/Rij rat, did not fully develop its characteristic features. However, when all groups of rat where tested for pentyletetrazole-induced convulsion, animals perinatally treated with ethanol were less responsive in comparison to their respective controls. These results are in agreement with previous reports showing how the genetic background can directly influence the teratogenic effects of alcohol, and this can be strictly related to the variability in the observation of offspring anomalies in humans which has lead to a 5-category classification system for individuals exposed to alcohol in uterus.

Enhancement of anti-absence effects of ethosuximide by low doses of a noncompetitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist in a genetic animal model of absence epilepsy.

N-Acetyl-1-(4-chlorophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline (THIQ-10c) is a noncompetitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist that has been demonstrated to antagonize generalized tonic-clonic seizures in different animal models of epilepsy. In the study described here, we tested the potential effect of such a compound alone or co-administered with ethosuximide in a genetic animal model of absence epilepsy, the WAG/Rij rat. The intraperitoneal or intracerebroventricular microinjection of THIQ-10c alone was unable to significantly modify the number and duration of spike-and-wave discharges (SWDs). In contrast, intracerebroventricular administration of AMPA induced a dose-dependent increase in the number of SWDs. THIQ-10c dose-dependently antagonized this effect. Furthermore, co-administration of THIQ-1c with ethosuximide (50mg/kg, intraperitoneally) was able to significantly increase the efficacy of the anti-absence drug. In conclusion, although noncompetitive AMPA receptor antagonists alone might not be useful in the treatment of absence epilepsy because of their low therapeutic index, combining them with ethosuximide might be helpful in controlling absence seizures in patients not tolerating this drug or in refractory patients.

Role of CYP3A5 in abnormal clearance of methadone.

OBJECTIVE: To report a case of unusually low concentrations of methadone in a polydrug abuser during maintenance treatment with methadone. CASE SUMMARY: A 25-year-old man (weight 55 kg, height 165 cm) with a 12-year history of polydrug abuse was admitted to an opiates withdrawal methadone program. At the time of our observation, he was using both cannabinoids and heroin; no other medical conditions were discovered. Within the opiates withdrawal methadone program, under medical supervision, the patient started methadone therapy (20 mg/day). Two weeks later, an Abuscreen assay for methadone screening in the urine was negative and, to prevent the development of withdrawal symptoms, the dose of methadone was increased to 60 mg/day. One day later, the patient was asked to collect another urine sample in the presence of a nurse. The Abuscreen for methadone in urine remained negative. Evaluation of urinary samples collected over 24 hours documented low concentrations of methadone and high levels of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (the primary metabolite of methadone). Evaluation for the presence of the most common polymorphisms in the cytochrome P450 and P-glycoprotein genes showed that the patient was heterozygous for the CYP3A5(*)1 allele and for 2 single nucleotide polymorphisms in the P-glycoprotein gene (1236C/T and 3435C/T). DISCUSSION: In this patient, poor methadone adherence was ruled out because of the presence of physicians and nurses during both methadone maintenance treatment and Abuscreen screening. Moreover, because the patient reported only heroin and cannabis at the time of evaluation, drug interactions were ruled out as possible causes for the rapid clearance of methadone. CONCLUSIONS: In this case, CYP3A5 polymorphism may have played a role in the rapid methadone metabolism.

Venlafaxine-propafenone interaction resulting in hallucinations and psychomotor agitation.

OBJECTIVE: To report a case of visual hallucinations and psychomotor agitation probably induced by an interaction between venlafaxine and propafenone. CASE SUMMARY: An 85-year-old woman was admitted for evaluation of a mood disorder on March 20, 2006. Her general practitioner had prescribed sertraline for treatment, which had started about 6 months earlier. The patient's medical history included hypertension, supraventricular tachycardia, chronic bronchitis, and arthritis, for which she received ramipril, ticlopidine, torsemide, theophylline, acetaminophen, and triazolam. The patient had also received propafenone 150 mg every 12 hours for 3 years. Results of biochemical tests were normal; however, a computed tomography (CT) scan of the brain showed signs of cortical atrophy. Sertraline was discontinued after a few days because of its reduced effectiveness and was replaced with extended-release venlafaxine 75 mg/day. No other changes to the patient's drug therapy were made. Four weeks later, because of the persistence of psychiatric disturbance, the venlafaxine dosage was increased to 150 mg/day. Ten days later the patient returned to our observation due to the onset of visual hallucinations lasting about 2 hours, especially at night, and psychomotor agitation. Venlafaxine was discontinued, with a complete remission of hallucinations and psychomotor agitation in about 4 days. The Naranjo probability scale indicated a probable relationship between venlafaxine and the patient's symptoms. Citalopram was started one month later for the persistence of mood disorders, with no adverse effects. DISCUSSION: A CT scan documented signs of cortical atrophy in our patient's brain but excluded vascular brain injury, while clinical evaluation and anamnesis excluded a relationship between hallucinations and cortical atrophy. Genetic and pharmacologic factors may be involved in venlafaxine-induced adverse effects. Venlafaxine is metabolized primarily by CYP2D6 and is a substrate of P-glycoprotein. Propafenone, a known substrate and inhibitor of both CYP2D6 and P-glycoprotein, could therefore be involved in venlafaxine-induced hallucinations through the increase of venlafaxine plasma concentrations. CONCLUSIONS: To prevent the onset of clinical disturbances during venlafaxine treatment, we suggest careful evaluation of concomitant treatment with CYP2D6 or P-glycoprotein inhibitors (eg, propafenone) and, when possible, venlafaxine serum concentration monitoring.

Apomorphine-induced neurodegeneration in Mongolian gerbil hippocampus.

Animal experiments using pharmacological agents acting on the dopaminergic system, such as apomorphine, have been used as suitable models of schizophrenia, based on the dopaminergic hypothesis of this disorder. To determine whether dopaminergic hyperactivity may produce neuropathological changes, young Mongolian gerbils were treated with apomorphine (0.45 mg/kg) and the hippocampal CA1 region was subsequently studied by transmission and scanning electron microscopy. Acute subcutaneous administration of apomorphine induced pronounced degenerative changes in hippocampal neurons, such as swollen dendrites and axons in the neuropil and swelling of synaptic endings with a decrease in the number of synaptic vesicles. In conclusion, we think that this animal model may provide important indications about a possible dopaminergic hyperactivation mechanism, that could produce pathological changes in the hippocampus similar to those encountered in psychotic patients.

Adverse effects of atypical antipsychotics in the elderly: a review.

Use of antipsychotic medication is very common in the elderly and often an essential therapy. However, successful treatment in the elderly requires appropriate multidimensional assessment of the patient, knowledge of possible multiple co-morbidities, and awareness of the complexities of polypharmacy, age-dependent changes in pharmacokinetics and pharmacodynamics, and drug-drug interactions in this age group. Antipsychotics are known to have a number of adverse effects. New antipsychotics, such as amisulpride, clozapine, olanzapine, risperidone, quetiapine, ziprasidone, zotepine and aripiprazole, may interact with both dopamine and serotonin receptors. However, compared with conventional antipsychotics, they are less likely to cause extrapyramidal symptoms and are better tolerated in the elderly. At the same time, consistent differences between atypical antipsychotics have been demonstrated. Use of clozapine, for example, is limited by the risk of agranulocytosis, whereas this is not a disadvantage of olanzapine, risperidone, quetiapine and, more recently, ziprasidone, which are being widely used with good results in schizophrenia. However, use of the latter agents to treat the behavioural and psychological symptoms of dementia has been restricted because of recent observations of increased cardiovascular events in patients taking risperidone and olanzapine treatment. Nonetheless, careful review of the literature suggests that the available evidence does not support any causal relationship between use of risperidone or olanzapine and cardiovascular events. This article focuses on some of the main adverse effects commonly reported during administration of atypical antipsychotics to elderly patients. Such effects may be partly explained by age-related changes in pharmacokinetics and pharmacodynamics, and partly by the characteristics of the drugs themselves and their different receptor binding profiles.