Narcosis, and Convulsions

The stage of stimulation may be very short or even absent. With somewhat larger doses, it is usually succeeded by depression, first of the coordinating functions. The movements lose their purposive type and become choreic. This is followed by general narcosis and then by epileptiform convulsions, located chiefly in the midbrain. If the paralysis is rapid, the convulsive stage may not appear. 

The respiration is at first accelerated. During the spasms, it is irregular. The volume then diminishes. It may assume the Cheyne-Stokes type. Respiratory paralysis is the usual cause of death. This is also the first center to fail when the cocaine is applied locally to the fourth ventricle. 

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Symptoms of exposure Inhalation of vapors may cause depression of central nervous system, narcosis, and convulsions (Patnaik, 1992). An irritation concentration of 300.00 mg/m in air was reported by Ruth (1986). 

The minimal lethal dose for rabbits by oral administration was 1.25-2 g/kg rapid narcosis and convulsive movements preceded death. Sublethal doses caused narcosis with spasmodic head jerking salivation and lacrimation were also observed hepatocellular degeneration was apparent at autopsy. 

Some toxins in mushrooms are alkaloids that cause central nervous system effects of narcosis and convulsions. Hallucinations occur in subjects who have eaten mushrooms that contain psilocybin. The toxic alkaloid muscarine is present in some mushrooms. 

ANTIFUNGAL activity. It produces narcosis and convulsions in animals, also hypotension and respiratory depression. It has been used (in eastern Europe) as an antitussive with similar potency to codeine. 

Methylcyclohexanol is mildly toxic. Inhalation may produce mild irritation of the eyes and the respiratory system, and headache. Studies in rabbits showed that this compound could cause rapid narcosis and convulsion at sublethal doses. The minimum lethal dose by oral administration was 2000 mg/kg. Severe exposure may produce narcosis in humans. Skin absorption may canse dermatitis. 

Inhalation of its vapors can produce depression of the central nervous system, which can progress to narcosis and convulsion as the concentration increases. A 30-minute exposure to a 5000-ppm concentration caused convulsions in rats. Acute as well as chronic exposure to high concentrations can cause liver damage. 1,2,3-Trichloropropane is more toxic than its 1,1,1-isomer. Acute oral toxicity is moderate, with LD50 values ranging between 300 and 550 mg/kg in different species of experimental animals. The liquid is a strong irritant to the eyes. 

Methyl mercaptan (CAS 74-93-1) Causes delayed-onset pulmonary edema. CNS effects include narcosis and convulsions. Reported to have caused methemoglobinemia and hemolysis in a patient with G6PD deficiency (see p 261). 

Rabbits exposed 6 hours/day to 2 72 ppm over a 10-week period showed slight eye irritation at 997 ppm additional effects were salivation, lethargy, narcosis, mild convulsive movements, and some deaths. Lethal doses of cyclohexanol produced slight necrosis of the myocardium and damage to the lungs, liver, and kidneys. The application of 10 ml of cyclohexanol to the skin of a rabbit for 1 hour/day for 10 days induced narcosis, hypothermia, tremors, and athetoid movements necrosis, exudative ulceration, and thickening of the skin occurred in the area of contact. Ten microliters applied directly to the cornea of rabbits caused moderate to severe irritation. ... 

No effects have been reported in humans. Rabbits did not survive exposure for 70 minutes to 15,227ppm conjunctival congestion, dyspnea, rapid narcosis, and severe convulsions preceded death. Exposure to 10,000... 

Toxicity and health effects Studies have shown that exposure to vapors causes irritation to the eyes, severe burns, loss of vision, irritation to the nose and throat, headache, and pulmonary edema. Exposure to excessive vapor concentrations may cause nausea, vomiting, fainmess, coughing, chest pains, dizziness, depression, convulsions, narcosis, and possibly unconsciousness. Exposure of this nature is unlikely, however, because of the irritating properties of the vapor. Any direct skin contact with liquid -butylamine causes... 

HUMAN HEALTH RISKS Skin human Ig for 10 minutes Acute Risks irritation of skin destructive to mucous membranes and upper respiratory tract nausea weakness narcosis vertigo convulsions blistering attaxia slurred speech drowsiness Chronic Risks carcinogen reproductive disorders effects eyes, skin, respiratory system and CNS. 

The acute toxicity of methanethiol is similar to that of hydrogen sulfide. Inhalation of this gas can cause narcosis, headache, nausea, pulmonary irritation, and convulsions in humans. Other symptoms noted are acute hemolytic anemia, methemoglobinemia, and cyanosis. In humans, several hours exposure to about 5 ppm concentration of this gas can cause headache and nausea. Exposure to high concentrations can result in respiratory paralysis and death. The 2-hour... 

Toxicology S. is rapidly absorbed after oral uptake, is metabolized mainly in the liver, and rapidly eliminated. Symptoms of intoxication are initial restlessness, anxiety, vomiting, then convulsions of the extensor muscles (1 or more/minute), the convulsions are again triggered by external stimuli. Therapy for acute poisoning gastrolavage and administration of activated charcoal - for severe poisoning barbiturate narcosis and administration of muscle relaxants. 

P Homochelidonine was examined by Meyer and von Engel, and the results, as quoted by Schmidt, indicate that in frogs -homochelidonine behaves like chelidonine, and that in mammals it causes slight narcosis and a transitory fall in blood pressiu e, followed by convulsions of the type induced by camphor, slowing of the pulse and, in large doses, paralysis of the vaso-motor centres. It also paralyses the ends of the sensory nerves. ... 

Peters s results for corycavine and corycavamine indicate that these two alkaloids produce narcosis in frogs followed by paralysis of the spinal cord, and in mammals increased secretion of tears and saliva and epileptiform convulsions without increase of reflex irritability they also adversely affect the heart. ... 

Time scaling Default values of n=3 and n=l for shorter and longer time-scaling durations, respectively, with respective k value of 2,058 ppm-h and 42 ppm-h, because no data were available for time scaling the central nervous system end points of convulsions and narcosis. Because of the long exposure duration of the key study, the 10-min value was not time scaled but was set equal to the 30-min AEGL-3. 

Cats exposed to 5000 ppm showed eye irritation and salivation at 18,500 there was dyspnea, convulsions, and narcosis 54,000 ppm was lethal within minutes. Repeated exposure at 6600 ppm resulted in weight loss and weakness. 

Toxicology. Nitromethane, in animals, affects the central nervous system, causing convulsions and narcosis at high doses it is also a mild pulmonary irritant and may cause liver damage. 

Rabbits died from exposure to 10,000 ppm for 6 hours initial effects were weakness, ataxia, and muscular incoordination followed by convulsions. " The same concentration for 3 hours was not fatal. Autopsy of animals exposed to lethal concentrations showed focal necrosis in the liver and moderate kidney damage. Lower concentrations produced slight irritation of the respiratory tract, followed by mild narcosis, weakness, and salivation, but no evidence of eye irritation. 

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