Without treatment, withdrawal of a short-acting barbiturate can cause the following: Within the first 12 to 20 hours: Increasing restlessness, tremulousness, and weakness By the 2nd day: More prominent tremulousness, sometimes increased deep tendon reflexes, and increased weakness During the 2nd and 3rd days: Seizures (in 75% of patients who were taking ≥ 800 mg / day), sometimes progressing to status epilepticus and death From the 2nd to the 5th day: Delirium, insomnia, confusion, frightening visual and auditory hallucinations, and often hyperpyrexia and dehydration Diagnosis of Sedative Toxicity Usually a clinical diagnosis Diagnosis of sedative intoxication is usually made clinically.