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Benzodiazepines are widely used drugs. However, their chronic use has revealed that they can lead to dependence. The objective of this study is to review the different pharmacological strategies used in the management of benzodiazepine dependence and new trends in pharmacological interventions.
We searched in MEDLINE and in the Cochrane Database System Review, selecting studies from 1980 until the present, in which a pharmacological intervention was made for benzodiazepine detoxification in mono-dependence cases.
There is a consensus about gradual rather than abrupt tapering benzodiazepines in benzodiazepine discontinuation. Other extended traditional strategy has been switching from short half-life to long half-life benzodiazepines before gradual taper. A great variety of agents have been used as adjuvant medication in Benzodiazepine Withdrawal Syndrome (BWS) with varying degrees of success. In the last years research has focus in the use of anticonvulsant drugs. Both carbamzepine and valproate, have demonstrated to be beneficial in benzodiazepine discontinuation. Also, preliminary data suggest that new anticonvulsant agents (gabapentin, pregabalin, oxcarbazepine and topiramate) could be helpful.
Although multiple drugs have been investigated for pharmacological management of BWS, only few have demonstrated significant efficacy. Anticonvulsant drugs are one of them. Both, carbamazepine and valproate, have shown benefits in reducing withdrawal severity. The available data currently support the use of new anticonvulsant (gabapentin, pregabalin, oxacarbazepine and topiramate), in the treatment of different drug-dependences such as alcohol, cocaine and opiate dependence. Moreover, there is a growing trend in the literature toward the use of these agents in benzodiazepine mono-dependence.
Startle reflex (SR) is a defensive response to sudden, intense stimuli. Prepulse inhibition (PPI) refers to the ability of innocuous sensory events to reduce SR. PPI has been described as an operational measure of sensorimotor gating that is reduced in several neuropsychiatric disorders, such as schizophrenia, but there is no extensive experience in addictions and alcoholism. The objective of this study was to examine the existence of impairments on SR and PPI in abstinent alcoholic males.
Subjects were 40 abstinent alcoholic males, aged 18 to 65 years (mean age 44.73), who had met DSM-IV criteria for Alcohol Dependence, being abstinent for more than a month at the moment they were tested. Participants underwent testing for PPI. Subjects were then compared with 35 equal controls.
Magnitudes of the SR were lower in abstinent alcoholic males when compared with controls. This differences were significant (p< 0,05) in trials with prepulse presented 30, 60 or 120 msec before the onset of startle stimulus. There was a significant less percentage of PPI when prepulse was presented 30 msec before the startle stimulus (p< 0,05).
Abstinent alcoholic males exhibit a decrease in the startle response magnitude and in the PPI of the SR. These data suggest that sensory information processing mechanisms could be damaged in abstinent alcoholic patients. The fact that these findings are common to other psychiatric disorders, could indicate the existence of a common vulnerability marker, and could explain the important comorbidity between alcoholism and other mental illness.
Impulsivity has been considered as a risk factor for alcohol dependence. Recent research is focusing on paradigms of the startle response (SR), specifically prepulse inhibition (PPI) and startle habituation (SH), as vulnerability markers for alcoholism. It has been demonstrated impairments in the PPI and the SH in offspring of alcoholics. It has also been shown, using personality questionnaires, that faster habituation may be associated with tendency toward impulsivity and behavioral disinhibition. Our goal is to study the correlation between impulsivity laboratory measures and the SR paradigms, in order to see if they could share a common base as endophenotypes for alcoholism.
The subjects were 40 abstinent alcoholic males, aged 18 to 65 years (mean age 44.73) and who had met DSM-IV criteria for Alcohol Dependence, being abstinent for more than a month at the moment they were tested. Participants underwent testing for PPI and habituation of the acoustic startle response. Impulsivity was assessed with three different laboratory measures: Continuous Performance Test (CPT), Stop-Signal Task and Differential Reinforcement for Low-Rate Responding (DRL6). Analyses were performed using SPSS v.10.0.
We found a significant positive correlation between CPT-tasks and SH (p< 0,01), and Stop-Signal Task-tasks and SH (p< 0,05), but not with DRL6-tasks. No significant correlation was demonstrated between impulsivity measures and PPI.
Our findings suggest the existence of a common base between impulsivity and SH as vulnerability markers for alcohol dependence. Further studies are needed to assess if both could share a common genetic origin.
Alcoholism is a chronic relapsing disorder characterized by compulsive drinking, alcohol seeking, loss of control over alcohol consumption, and impaired social and occupational functioning. Treatment of Alcohol Dependence (AD) comprises two steps, detoxification and relapse prevention (RP). Traditionally, long half-life benzodiazepines have been the most widely used agents for alcohol detoxification. On the other hand, disulfiram, naltrexone and acamprosate are the three drugs that have been approved for relapse prevention. In the last decades, nevertheless, there is a growing interest in the use of anticonvulsant drugs in the management of both, detoxification and relapse prevention of alcohol.
To review the different pharmacological strategies in which an anticonvulsant was used in the management of AD.
We searched in MEDLINE and in the Cochrane Database System Review, selecting all studies from 1980 until present, in which a pharmacological intervention with anticonvulsant agents was made for alcohol detoxification or RP.
The most tested anticonvulsant drugs are the classical Carbamazepine and Valproate. Both have demonstrated to be efficacious in Alcohol Withdrawal Syndrome and RP. However, the use of these agents has been limited by their hepatic and hematologic toxicity. Novel anticonvulsants such as Gabapentin, Pregabalin, Topiramate, Oxcarbazepine and Zonisamide have also been found to be effective, with the advantage of rapid onset of action, lower toxicity and fewer side effects.
Anticonvulsants are efficacious and safe agents in the management of AD. Further randomized, double-blind, placebo-controlled trials are warranted to increase the evidence of the use of these agents.
Neuropsychiatric disturbances, from depression to psychosis and attempted or successful suicides are reported during interferon (IFN) therapy for chronic viral hepatitis. IFN schedule and history of psychiatric illness are not enough to predict who will develop symptoms.
To assess the prevalence of depression during IFN therapy; to test whether a computerized version of the Minnesota Multiphasic Personality Inventory (MMPI) is a sensitive and reliable test for the early identification of patients at risk of depression before IFN therapy is started; and whether and how the depression can be cured. Patients. 185 patients treated with IFN.
Before therapy, all patients underwent an MMPI and a clinical examination for identification of depressive symptoms.
Thirty-one patients developed a psychiatric disorder, 11 of them requiring treatment. Among the 18 patients with MMPI positive tests, 16 developed a psychiatric disorder (sensitivity of 0.58). Among the 154 who did not develop psychiatric side effects, 152 had a negative MMPI (specificity: 0.99). Severe psychiatric disorders (8 patients) were successfully treated with antidepressant drugs.
Psychiatric side effects are easy to see during IFN therapy. An accurate psychiatric evaluation should be considered on all patients before treatment. However, as this specific examination cannot always be performed because of the lack of psychiatrists in liver units, it is necessary to identify tests, that are easy to carry out, reproducible, self-administered and inexpensive in order to screen all patients. If depression develops, it should be treated aggressively, and selective serotonin re-uptake inhibitors are the anti-depressant of choice.
It is considered that cocaine could be a risk factor for the development of alcohol dependence. Prospective studies in healthy subjects support the idea that alcohol and cocaine use decreases the subjective feeling of inebriation and increases the sense of being “high”. The consumption of both drugs may accentuate the reinforcing properties of both drugs, thus increasing the vulnerability of subjects for developing drug dependence. Our objective was to investigate whether the risk for the development alcohol dependence is related with the interaction of both drugs at reward brain mesolimbic centres or it depends on the effect of cocaine at that brain mesolimbic structures.
The final sample (n = 112) comprised 4 groups: sample 1(alcohol-group), n = 47; sample 2 (alcohol-cocaine group), n = 35; sample 3 (cocaine-group), n = 30. The control group (n = 61) was selected to have matching demographic characteristics. After detoxification, alcohol-related pictures were compared to standardised appetitive, aversive and neutral control scenes using an acoustic-startle test.
Alcohol-startle magnitudes were lower in cocaine-dependent patients (samples 2 and 3) than in alcohol patients (sample 1). Subjects with cocaine dependence also exhibited lower magnitudes than participants included in the OH-group after viewing appetitive and aversive slides.
Our findings support the hypothesis that effects of cocaine at dopamine mesolimbic structures provoke higher appetitive responses to alcohol-cues. It is tempting to speculate that cocaine use may induce significant reduction in dopamine D2 receptors, which would increase the likelihood of developing dependence for other substances as alcohol used at the same time than cocaine.
It is well known that impulsivity and stress are risk factors for the development of addictive disorders, and more specifically alcohol dependence. Impulsivity has two dimensions: behavioural inhibition and delay of reward. The Fear- Conditioning paradigm of the Startle response (SR), which refers to the potentiation of the startle amplitude after the exposure to aversive stimulus, can be used as a stress test. The aim of this study was to explore the correlation between impulsivity laboratory tasks and the Fear-Conditioning (FC) paradigm of the SR as risk factors for the development of alcohol dependence.
The sample included 40 abstinent alcoholic men, who met DSM-IV criteria for Alcohol Dependence and had been abstinent for at least one month. Impulsivity was assessed using two laboratory tests: Stop-Signal Task (SST) and Differential Reinforcement for Low-Rate Responding (DRL6). The FC paradigm of the SR was used as a stress test. Patients were compared to 40 matched controls.
We found a positive correlation between SST tasks and the FC paradigm of the SR (p < 0,05) and a negative correlation between the DRL6 tasks and the FC paradigm of the SR (p < 0,05) in the patient's group. This significant correlation was not found in controls.
Impulsivity and stress are significantly correlated in alcohol dependent patients. This means that while healthy subjects cope with stress, alcohol dependent patients react with higher impulsivity when they are exposed to stress situations and this could lead them to drink alcohol to relieve anxiety and depressive symptoms.
Lithium has been used in the treatment of pregnant women with bipolar disorder for many decades but information on the effects of its exposure on perinatal variables is scarce.
To determine the effects of in-utero exposure to lithium on neonatal outcomes among infants born to women with treatment with lithium during pregnancy.
Prospective and observational study including all consecutive cases of pregnant women with bipolar disorder type I or II (N = 22) and maintenance treatment with lithium monotherapy (n=13) or polytherapy (n=9), attended at the PERINATAL PSYCHIATRY PROGRAM CLÍNIC-BARCELONA between 2005 and 2012. We evaluated sociodemographic data, lithium plasma concentrations in maternal blood and umbilical cord, obstetric and neonatal variables.
No statistically significant differences were found regarding sociodemographic data between both groups. Rates for umbilical cord:maternal plasma lithium levels were higher in women treated with polytherapy than in women who received lithium alone (1.08 vs. 1.05). Neonates exposed to polytherapy had a higher weight percentile at birth (p70 vs p50) and greater gestational age (39.72 vs. 38.28 weeks), than those exposed to lithium alone. Acute neonatal complications were more frequently observed in infants that were exposed to lithium monotherapy (33.3% vs. 38.50), being all complications transitory and not severe.
The infants exposed to lithium polytherapy presented a higher weight at birth compared to those who received lithium monotherapy. However, no statistically significant differences were found between treatment groups. Further research is needed to better clarify safety of lithium and its effect on neonatal outcomes.
Major depressive disorder is a serious mental disorder with high prevalence and recurrence rate. Once depression is diagnosed, effective pharmacological treatments must be rapidly initiated. Depression etiology and responsiveness to antidepressants have been related to the activity of the hypothalamic-pituitary-adrenal (HPA) axis. Depressed subjects do not respond equally to the same drug. This variability could be explained by interindividual genetic differences related to HPA axis, including CRHR1 receptor.
To associate the salivary cortisol levels, prior to antidepressant treatment, and the CRHR1 rs242939 polymorphism with the response to therapy with fluoxetine.
We performed a pharmacogenetic prospective longitudinal study including clinic follow-up, endocrine and genetic evaluations. After diagnosis, patients started the pharmacotherapy. the severity of the disease and clinical response were evaluated by the Hamilton Depression Rating Scale (HAM-D). Rapid and slow responses were considered as reductions in the HAM-D scores of at least 50% at the third and eight weeks respectively.
157 patients were recruited. Salivary cortisol levels at 8:00AM were lower in rapid responders than in not responders (p-value = 0.0122). No differences were observed after eight weeks of treatment. the rs242939 polymorphism was in Hardy Weinberg equilibrium (p = 0,24) and was significantly associated with early response (p = 0.019). there was no association after two month of therapy.
Discussion and conclusions:
Alterations in the CRHR1 receptor may significantly impact the regulation of stress response. the association observed in this study may be related with some refractoriness in the regulation of CRHR1 gene in non responders.
Alcoholics show attentional bias when viewing alcohol-related pictures, a low magnitude of the startle response when viewing alcohol-related cues, and a poor inhibitory control. However, it has not been studied which clinical and drinking variables modulate these paradigms.
To explore which clinical and drinking variables modulate attentional bias, affective modulation of the startle reflex and behavioural inhibition in alcoholics.
127 alcoholics were tested with 3 psychophysiological tasks: the dot probe task (attentional bias), the startle response when viewing alcohol cues (affective modulation of the startle reflex) and the Stop Signal Task-Modified (behavioural inhibition). Clinical variables were evaluated using the Barrat Scale (BS), the Hamilton Anxiety Scale (HAS) and the Hamilton depression Scale (HDS). Drinking variables were assessed with the Timeline follow back (TLF).
Attentional bias correlated with the number of drinking days, mean intake of alcohol and score of the HDS. Affective modulation of the startle reflex correlated with mean intake of alcohol, scores of the HDS and the BS. Behavioural inhibition correlated with scores of the HDS, the HAS and the BS.
Psychophysiological tasks correlated with drinking variables (mean intake of alcohol and the number of drinking days) and clinical variables (impulsivity, anxiety and depression). Clinicians should take these variables into account when treating alcoholics because they can be controlled with appropriate pharmacological treatment and it is well known that attentional bias, affective modulation of the startle reflex and behavioural inhibition are implicated in maintaining alcohol consumption and increasing the risk of relapse.
Current data suggest that at least three psychophysiological paradigms are involved in Alcohol Dependence: attentional bias; affective modulation of the startle reflex and behavioural inhibition. These three paradigms have not been studied together in a sample of alcohol dependent subjects.
To show that the performance on these three psychophysiological processes allows discriminating alcohol dependent subjects (with different severity) from healthy controls.
59 alcohol dependent subjects were assessed with the following three psychophysiological tasks: The dot probe task (which assesses attentional bias), the startle response when viewing alcohol cues (which evaluates affective modulation of the startle reflex), and the Modified- Stop Signal-Task (which measures behavioral inhibition). The Severity of Alcohol Dependence Scale (SAD) was used for grouping patients based on their dependence severity. 52 healthy subjects were assessed as the control group.
All three paradigms correctly discriminated between patients and controls. Patients were divided into three subgroups according to their scores on the SAD (mild, moderate and severe dependence). The performance of the three groups in the three paradigms studied was also different. Patients with more severe dependence had more attentional bias for alcohol cues, exhibited lower magnitudes of startle response when viewing alcohol cues, and showed lower capacity to inhibit their behaviour when words related to alcohol were being seen.
Subjects with alcohol dependence showed different psychophysiological response patterns compared to controls in the three paradigms studied. These response patterns seem to be associated with the severity of dependence, and they could be used to determine the outcome of the treatment in patients with alcohol dependence.
Most of elderly onset psychosis present as a consequence of one or more organic processes. We present the case of an 81-year-old patient with diagnosis of a posterior fossa meningioma. It emerged with abrupt positive symptoms of psychosis with important family and social disruption. The interest of the case lies in the low frequency of psychiatric symptoms associated to this type of tumor, given its location. Thus, these symptoms may be explained, by normal pressure hydrocephalus (NPH) secondary to the tumor.
To highlight the importance of performing a complete organic screening in elderly onset psycotic patients.
Material and method
From the mentioned case, we performed a literature review of psychopathology associated with NPH.
Psychiatric examination demonstrated parasitization delusions and delusional misinterpretations; tactile and visual zoomorphic hallucinations were also present. They were compatible with Ekbom syndrome; anxiety and behavioral disorganization were prominent. We introduced treatment with risperidone 0.5 mg/12 h with important decrease of positive psychotic symptoms. Currently, the patient is waiting for a ventricular-peritoneal shunt.
The NPH usually presents with memory failures, psychomotor slowing, problems in calculating and writing. It may progress to a neurological impairment so intense that may be indistinguishable from Alzheimer's disease. From a psychopathological point of view, affective or psychotic symptoms and/or behavioral disorganization may also appear. In few cases, HNT onset shows with prominent psychiatric symptoms instead of neurological impairment. These symptoms may improve with pharmacological and surgical treatment. Thus, it is important to get an accurate diagnosis.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Parasomnias are a category of sleep disorders in which abnormal events occur during sleep, due to inappropriately timed activation of physiological systems.
we report the case of a 41-year-old female who has no psychiatric history. The patient went to emergency department because when she was starting to sleep, in the first state of sleep, she felts a sensation of paralysis in all her body, with incapacity for breathing, chest oppression and tactile hallucinations like something or someone was touching her entire body. Due to that, the patient awoke frightened, with high levels of anxiety, with heart palpitations, shortness of breath, trembling, choking feeling, sweating, nausea and fear of dying. When the patient arrived to the emergency department, she was suffering a panic attack, thinking that she could have some kind of neurological disease or she was suffering a heart attack. after treating the panic attack with 1 mg of lorazepam, all the symptoms subsided gradually.
in this case report, we present a patient with a new-onset parasomnia, with hypnagogic hallucinations and a panic attack at the awakening. It is known that stress factors are closely associated with parasomnias, as we can see in this case because the patient was moving and she was sleeping in a new place.
Parasomnias are very frequently present in general population and they can trigger intense anxiety status that can lead to panic attacks.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Episodes of time-limited acute psychosis, with full recovery in between, are categorized as acute polymorphic psychotic or brief psychotic disorders. Leonhard described the three forms of cycloid psychosis (CP). Perry considers it a separate entity.
We report the case of a 54-year-old male, with a 9-year history of brief psychotic disorders. He was admitted to an inpatient unit after a 4-day episode of persecutory delusion, leading to high emotional repercussions and isolation at home. Euthymia was present. Previous admissions, 9 and 5 years before, presented similar clinical pictures. Treatment with low dose paliperidone during 6-month periods had led to the complete resolution of the episodes (restitutio ad integrum: no psychotic manifestations and the ability to run his business). In this episode, 8 days after the reintroduction of 12 mg of paliperidone per day, cessation of the symptoms took place. Careful reconstruction of the clinical history showed no stressors or drug consumption. And immediately previous 5-day phase of insomnia, hyperactivity and expenditure was described by the patient's wife.
Three inpatient admissions, a careful clinical history and a thorough review of the evidence regarding Perris criteria led to a diagnosis of CP.
CP, a classical nosological approach, is helpful in a clinical setting, as it might imply different prognosis and treatment. Recognition of CP, not included as an entity by the major diagnostic systems, requires a high index of suspicion.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
To measure caregivers’ and clinicians’ perception of false memories in the lives of patients with memory loss due to Alzheimer’s disease (AD) and mild cognitive impairment (MCI) using a novel false memories questionnaire. Our hypotheses were that false memories are occurring as often as forgetting according to clinicians and family members.
This prospective, questionnaire-based study consisting of 20 false memory questions paired with 20 forgetting questions had two forms: one for clinicians and the other for family members of older subjects. In total, 226 clinicians and 150 family members of 49 patients with AD, 44 patients with MCI, and 57 healthy older controls (OCs) completed the questionnaire.
False memories occurred nearly as often as forgetting according to clinicians and family members of patients with MCI and AD. Family members of OCs and patients with MCI reported fewer false memories compared to those of the AD group. As Mini-Mental State Examination scores decreased, the mean score increased for both forgetting and false memories. Among clinicians, correlations were observed between the dementia severity of patients seen with both forgetting and false memories questionnaire scores as well as with the impact of forgetting and false memories on daily life.
Patients with AD experience false memories almost as frequently as they do forgetting. Given how common false memories are in AD patients, additional work is needed to understand the clinical implications of these false memories on patients’ daily lives. The novel false memories questionnaire developed may be a valuable tool.
The aim of this study was to determine the prevalence and risk factors for human papillomavirus (HPV) infection in the Southern region of the State of Bahia, evaluating the performance of alternative complementary methods for cervical lesion detection. Cervical samples from women who attended healthcare units were collected and diagnosed by visual inspection, cervical cytology and nested polymerase chain reaction (PCR). Moreover, hemi-nested PCR was performed to detect different HPV genotypes. The prevalence of HPV infection was 47·7%, with genotype 16 detected in most cases. Infection was associated with dyspareunia and bleeding (P < 0·001, odds ratio (OR) 5·6, 95% confidence interval (CI) 2·815–11·14) and hormonal contraceptive use (P = 0·007, OR 2·33, 95% CI 1·25–4·34). There was a positive correlation between positive PCR and positive visual inspection, cervical cytology and symptoms reported. Furthermore, visual inspection was twice as specific, and had a greater positive predictive value than cytology. We showed a high prevalence of HPV infection in Southern Bahia, with HPV 16 being the most common type, and visual inspection being most effective at detecting HPV lesions, corroborating the suggestion that it can be applied in routine gynecologic examinations for low-income populations.
Research suggests that lesbian, gay and bisexual (LGB) adolescents have a higher risk of suicidal behaviours than their heterosexual peers, but little is known about specific risk factors.
To assess sexual orientation as a risk factor for suicidal behaviours, and to identify other risk factors among LGB adolescents and young adults.
A systematic search was made of six databases up to June 2015, including a grey literature search. Population-based longitudinal studies considering non-clinical populations aged 12–26 years and assessing being LGB as a risk factor for suicidal behaviour compared with being heterosexual, or evaluating risk factors for suicidal behaviour within LGB populations, were included. Random effect models were used in meta-analysis.
Sexual orientation was significantly associated with suicide attempts in adolescents and youths (OR=2.26, 95% CI 1.60–3.20). Gay or bisexual men were more likely to report suicide attempts compared with heterosexual men (OR=2.21, 95% CI 1.21–4.04). Based on two studies, a non-significant positive association was found between depression and suicide attempts in LGB groups.
Sexual orientation is associated with a higher risk of suicide attempt in young people. Further research is needed to assess completed suicide, and specific risk factors affecting the LGB population.
I deficiency is still a worldwide public health problem, with children being especially vulnerable. No nationwide study had been conducted to assess the I status of Spanish children, and thus an observational, multicentre and cross-sectional study was conducted in Spain to assess the I status and thyroid function in schoolchildren aged 6–7 years. The median urinary I (UI) and thyroid-stimulating hormone (TSH) levels in whole blood were used to assess the I status and thyroid function, respectively. A FFQ was used to determine the consumption of I-rich foods. A total of 1981 schoolchildren (52 % male) were included. The median UI was 173 μg/l, and 17·9 % of children showed UI<100 μg/l. The median UI was higher in males (180·8 v. 153·6 μg/l; P<0·001). Iodised salt (IS) intake at home was 69·8 %. IS consumption and intakes of ≥2 glasses of milk or 1 cup of yogurt/d were associated with significantly higher median UI. Median TSH was 0·90 mU/l and was higher in females (0·98 v. 0·83; P<0·001). In total, 0·5 % of children had known hypothyroidism (derived from the questionnaire) and 7·6 % had TSH levels above reference values. Median TSH was higher in schoolchildren with family history of hypothyroidism. I intake was adequate in Spanish schoolchildren. However, no correlation was found between TSH and median UI in any geographical area. The prevalence of TSH above reference values was high and its association with thyroid autoimmunity should be determined. Further assessment of thyroid autoimmunity in Spanish schoolchildren is desirable.
The protected agriculture has gained great importance worldwide in the past 10 years. For example in the case of production in greenhouse conditions, that records an annual growth of 20%.
An important aspect greenhouse production is the medium used for growth of the plant, which may be an organic or inorganic substrate.
One of the advantages of the use of regional substrates is the availability and lower cost, and further organic in gives the tendency to manage sustainable production systems.
The organic substrates alone or in mixtures improve conditions for plant growth in terms of physical, chemical and biological as a perspective.
A wide variety of materials that can be used as agricultural substrates, but there are criteria to be considered for its election as: plant requirements, conforming as possible to the ideal characteristics of a substrate and effect on the environment.
Overall, we can summarize that a substrate for growing plants is any material that can provide attachment, oxygen and enough water for optimal development of the same, or in nutrient case requirements can be covered with a single material or combination with others.
In this paper the tomato crop is presented comparing two production systems to determine the yield and fruit quality under plastic cover, high densities of drip irrigation and using the tezontle as substrate, as this provides good drainage, almost no contribution nutrients and slightly neutral PH. And also allows us to transplant to a larger pot without disturbing the root and provides the necessary aeration.