Benzodiazepines intoxication symptoms

FIGURE 13-33. Acute withdrawal of benzodiazepines in a benzodiazepine-dependent individual. If benzodiazepines are suddenly stopped in a patient who is tolerant to them and dependent on them, benzodiazepine receptors will experience this as an acute deficiency at their binding sites. Thus, the presence of desensitized benzodiazepine receptors actually worsens the impact of benzodiazepine discontinuation. The brain, which is used to too much benzodiazepine at its receptors, is suddenly starved for benzodiazepine. Therefore, the brain experiences the reverse of benzodiazepine intoxication, namely, dysphoria and depression instead of euphoria anxiety and agitation instead of tranquility and lack of anxiety insomnia instead of sedation and sleep muscle tension instead of muscle relaxation and at worst, seizures instead of anticonvulsant effects. These actions continue either until benzodiazepine is replaced or until the receptors readapt to the sensitivity they had prior to excessive benzodiazepine use. Alternatively, one can reinstitute benzodiazepines but taper them slowly, so that the receptors have time to readapt during dosage reduction, and withdrawal symptoms are prevented. 

Secobarbital exhibits the same pharmacologic properties as other members of the barbiturate class. Most nonmedical use is with short-acting barbiturates, such as secobarbital. Although there may be considerable tolerance to the sedative and intoxicating effects of the drug, the lethal dose is not much greater in addicted than in normal persons. Tolerance does not develop to the respiratory effect. The combination of alcohol and barbiturates may lead to fatalities because of their combined respiratory depressive effects. Similar outcomes may occur with the benzodiazepines. Severe withdrawal symptoms in epileptic patients may include grand mal seizures and delirium. 

Benzodiazepine (BZ) intoxication is manifested as slurred speech, poor coordination, swaying, drowsiness, hypotension, nystagmus, and confusion. Signs and symptoms of BZ withdrawal are similar to those of alcohol withdrawal, including muscle pain, anxiety, restlessness, confusion, irritability, haJlucinations, delirium, seizures, and cardiovascular collapse. Withdrawal from short-acting BZs (e.g., oxazepam, lorazepam, alprazolam) has an onset within 12 to 24 hours of the last dose. Diazepam, chlordiazep-oxide, and clorazepate have elimination half-lives (or active metabolites with elimination half-lives) of 24 to greater than 100 hours. So, withdrawal may be delayed for several days after their discontinuation. Sedative-hypnotic dependence is summarized in Table 73-2. 

Intoxication produced by Amanita muscaria and related Amanita species arises from the neurologic and hallucinogenic properties of muscimol, ibotenic acid, and other isoxazole derivatives that stimulate excitatory and inhibitory amino acid receptors. Symptoms range from irritability, restlessness, ataxia, hallucinations, and delirium to drowsiness and sedation. Treatment is mainly supportive benzodiazepines are indicated when excitation predominates atropine often exacerbates the delirium. 

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