Organophosphorous (OP) Nerve agents (NAs) are known as the deadliest chemical warfare agents. They are divided into two classes of G and V agents. Most of them are liquid at room temperature. NAs chemical structures and mechanisms of actions are similar to OP pesticides, but their toxicities are higher than these compounds. The main mechanism of action is irreversible inhibition of Acetyl Choline Esterase (AChE) resulting in accumulation of toxic levels of acetylcholine (ACh) at the synaptic junctions and thus induces muscarinic and nicotinic receptors stimulation. However, other mechanisms have recently been described. Central nervous system (CNS) depression particularly on respiratory and vasomotor centers may induce respiratory failure and cardiac arrest. Intermediate syndrome after NAs exposure is less common than OP pesticides poisoning. There are four approaches to detect exposure to NAs in biological samples: (I) AChE activity measurement, (II) Determination of hydrolysis products in plasma and urine, (III) Fluoride reactivation of phosphylated binding sites and (IV) Mass spectrometric determination of cholinesterase adducts. The clinical manifestations are similar to OP pesticides poisoning, but with more severity and fatalities. The management should be started as soon as possible. The victims should immediately be removed from the field and treatment is commenced with auto-injector antidotes (atropine and oximes) such as MARK I kit. A 0.5% hypochlorite solution as well as novel products like M291 Resin kit, G117H and Phosphotriesterase isolated from soil bacterias, are now available for decontamination of NAs. Atropine and oximes are the well known antidotes that should be infused as clinically indicated. However, some new adjuvant and additional treatment such as magnesium sulfate, sodium bicarbonate, gacyclidine, benactyzine, tezampanel, hemoperfusion, antioxidants and bioscavengers have recently been used for OP NAs poisoning.

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Delayed neurotoxic complications of chemical warfare agents (CWA), such as sulphur mustard (SM) and tabun, in human beings have not been reported in detail. We thus aimed to investigate possible neurotoxic complications of these agents in Iranian veterans 22-27 years after exposure. After co-ordination with the veteran foundation and obtaining the approval of the medical research ethics committee, 43 Iranian veterans with late complications of CWA exposure during the Iran-Iraq conflict were studied after obtaining signed written informed consent. Demographic and clinical findings were recorded on pre-designed forms. Neurological examination was performed by a neurologist. Routine biochemical tests were performed for all the patients. Electromyography (EMG), nerve conduction velocity (NCV) and electroencephalography (EEG) were carried out as clinically indicated. The majority of the patients (38) had been exposed to SM and only five patients to tabun. Hyperaesthesia was the most objective finding (72.1%). Fatigue (93%), paraesthesia (88.3%) and headache (83.7%) were the most common subjective findings in the patients. Sensory nerve impairments, including paraesthesia (88.3%), hyperaesthesia (72.1%) and hypoesthesia (11.6%), were the most common observed clinical complications. EMG and NCV were impaired in seven patients (16.3%) who were all SM-exposed patients but did not show any significant correlation with organ complications. EEG was negative even in the seized patients. Cholesterol, LDL and triglyceride levels were significantly above the normal ranges. Late neurological complications of CWA, particularly SM poisoning, are considerable even after three decades of exposure and require medical attention.

The most common delayed complication of sulfur mustard (SM) poisoning has been observed in the respiratory tracts. It was thus aimed to investigate the delayed respiratory complications in SM-exposed patients around 25 years before the study. Forty-three veterans with more than 25% disability of due to SM poisoning were investigated. Clinical examinations as well as pulmonary function test (PFT) were performed. High-resolution computed tomography (HRCT) of the lungs was done as clinically indicated. Triad of chronic cough, dyspnea, and expectoration were the most common symptoms that were recorded in 88.2%, 88.2%, and 64.7% of the patients, respectively. PFT abnormalities were detected in 44.18% of the patients. Restrictive pattern was the most common (41.86%), while pure obstructive pattern did not detect at all. Mixed pattern was significantly correlated with higher disability percentages among the veterans ( p < 0.001). Significant reverse correlation between the disability percentages and forced expiratory volume in 1 s/forced vital capacity ratio was obtained ( p = 0.010, r = -0.389). Air trapping was the most common abnormality in HRCTs (50%). Bronchiectasis (25%), pulmonary fibrosis (25%), and ground-glass attenuation (16.66%) were other common HRCT findings. Comparing with the previous studies on these patients, more restrictive and mixed pattern were observed. Moreover, bronchiolitis, bronchiectasis, and lung fibrosis were the main pathological findings in these patients.

Objectives:: While phenobarbital (PB) is commonly used for the management of seizures in newborns and pediat-rics, its administration may accompany with acute poisoning. We aimed to review the literature to find out the frequency of PB poisonings in newborns and children with seizures. Method:: Literature search was performed by two independent reviewers to find relevant articles about PB toxicity in neo-nates and pediatrics that were treated for seizure. Results:: 18 articles met the inclusion criteria and were included to this systematic review. The main reasons of PB poison-ing in studied patients were therapeutic intoxication. Reported signs of PB poisoning were lethargy, sedation, lack of suck-ing, fever, skin rash, hepatic inflammation and alopecia. Moreover, respiratory depression, encephalopathy, myocardial fail-ure, syndrome of inappropriate antidiuretic hormone, and coma were among the complications of acute PB toxicity in chil-dren and infants. Conclusion:: PB therapy for the management of seizures in newborns and children might be associated with poisoning. Alt-hough supportive and symptomatic treatments are available for PB overdose, it should be administered with caution, using drug monitoring to avoid toxicity.