Overdoses CNS depressants

Contraindications for antipsychotic therapy are few they may include Parkinson s disease, hepatic failure, hypotension, bone marrow depression, or use of CNS depressants. Overdoses of antipsychotics are rarely fatal, except for thioridazine, which is associated with major ventricular arrhythmias, cardiac conduction block, and sudden death. For other agents gastric lavage should be attempted even if several hours have elapsed since the drug was taken, because gastrointestinal motility is decreased and the tablets may still be in the stomach. Moreover, activated charcoal effectively binds most of these drugs and can be followed by a saline cathartic. The hypotension often responds to fluid replacement or pressor agents such as norepinephrine. 

IAsu ].p-ANP(7-28). aminosuccinic acid aspartic acid, aminosultopride amisulpnde. amiodarone [ban, inn, usan) (Cordarone ) is a benzofuran derivative, a (Class III) antiarrhythmic used mainly to treat ventricular arrhythmias, amiphenazole [ban, inn] (DHA 245 amifenazole) is a phenylthiazole and has similar properties as doxapram as a CNS STIMULANT and RESPIRATORY STIMULANT. It was previously used intramuscularly to treat barbiturate and other CNS DEPRESSANT overdose. 

Opiate overdose is a medical emergency that can result in respiratory and CNS depression. The opioid receptor antagonist naloxone immediately reverses cardiorespiratory depression. However, repeated naloxone administration is required, since the effects of naloxone last for 30 min, while opioid agonists can remain at potentially lethal blood levels for several hours. 

Death from overdose of barbiturates may occur and is more likely when more than 10 times the hypnotic dose is ingested. The barbiturates with high lipid solubility and short half-lives are the most toxic. Thus the lethal dose of phenobarbital is 6—10 g, whereas that of secobarbital, pentobarbital, or amo-barbital is 2-3 g. Symptoms of barbiturate poisoning include CNS depression, coma, depressed reflex activity, a positive Babinski reflex, contracted pupils (with hypoxia there may be paralytic dilation), altered respiration, hypothermia, depressed cardiac function, hypotension, shock, pulmonary complications, and renal failure. 

The lethal dose of mescaline varies because of the development of tolerance to the action of the drug. After a massive overdose, hypotension, bradycardia, CNS depression, and respiratory failure may be life threatening. Fatal intoxications from mescaline are rare, and fatalities associated with mescaline use are usually attributed to traumas resulting from altered perceptions. 

Overdose fatalities are rare unless benzodiazepines are taken with other CNS depressants. 

Because clove cigarettes also contain tobacco, they carry all of the hazards of regular tobacco smoking (Council on Scientific Affairs 1988). Several cases of serious medical illness have been associated with clove cigarettes in the United States (Guidotti et al. 1989). These include cases of hemorrhagic pulmonary edema, pneumonia, bronchitis, and hemoptysis. Because eugenol anesthetizes the respiratory tract, it inhibits the normal gag reflex and has led to aspiration pneumonia in at least one case. Accidental overdoses in children have led to CNS depression, urinary abnormalities, and anion-gap acidosis. These cases were treated successfully with supportive measures (Lane et al. 1991). 

Most authorities believe caffeine and other analeptics should not be used in overdose with CNS depressants and recommend other supportive therapy... 

Overdose symptoms may vary from CNS depression, including sedation, apnea, cardiovascular collapse, and death to severe paradoxical reaction, such as hallucinations, tremor, and seizures. 

Overdose produces CNS depression (including sedation, coma, and delirium), respiratory depression, and hypersalivation. 

Overdose results in CNS toxicity, including CNS depression, rapid gasping breathing, and seizures. 

Overdose may cause CNS depression, ataxia, coma, shock, hypotension, and death. 

Overdose produces cold or clammy skin, hypothermia, severe CNS depression, cyanosis, tachycardia, and Cheyne-Stokes respirations. 

Overdose produces cold or clammy ski n, hypothermia, and severe CNS depression, followed by high fever and coma. 

Overdose in patients older than 60 years may result in hallucinations, CNS depression, and seizures. 

Both zolpidem and zaleplon appear to be nonfatal in overdose. However, overdoses in combination with other central nervous system (CNS) depressant agents pose a greater risk. Recommended treatment consists of general symptomatic and supportive measures, including gastric lavage. Use of flumazenil may be helpful. 

Fatalities due to acute BZD overdose alone are extremely rare. Nevertheless, fatal overdoses with triazolam in the elderly have been reported ( 192, 193). Even with ingestion of massive doses, recovery appears to be rapid and without serious complications or aftereffects ( 194, 195, 196 and 197). Combined ingestion of BZDs with other CNS depressants (alcohol, barbiturates, narcotics, orTCAs), however, may result in severe CNS and respiratory depression or hypotension. Severity of symptoms appears to depend more on the type and quantity of the other drugs than on the BZD plasma level (194, 195, 196 and 197). 

Three stages of ethylene glycol overdose occur. Within the first few hours after ingestion, there is transient excitation followed by CNS depression. After a delay of 4-12 hours, severe metabolic acidosis develops from accumulation of acid metabolites and lactate. Finally, delayed renal insufficiency follows deposition of oxalate in renal tubules. The key to the diagnosis of ethylene glycol poisoning is recognition of anion gap acidosis, osmolar gap, and oxalate crystals in the urine in a patient without visual symptoms. 

Intravenous injection of naloxone dramatically reverses coma due to opioid overdose but not that due to other CNS depressants. Use of the antagonist should not, of course, delay the institution of other therapeutic measures, especially respiratory support. 

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