Central Nervous System
Occasionally a patient becomes somnambulistic and he may be disoriented and incoherent and show paranoid behavior. Rarely, excitement, tolerance, addiction, delirium, drowsiness, staggering gait, ataxia, lightheadedness, vertigo, dizziness, nightmares, malaise, mental confusion and hallucinations have been reported.
Leukopenia and eosinophilia have occasionally occurred.
Allergic skin rashes including hives, erythema, eczematoid dermatitis, urticaria, and scarlatiniform exanthems have occasionally been reported.
Some patients experience gastric irritation and occasionally nausea and vomiting, flatulence, diarrhea, and unpleasant taste occur.
Rarely, headache, hangover, idiosyncratic syndrome, and ketonuria have been reported.
DRUG ABUSE AND DEPENDENCE
Drug Enforcement Administration Schedule IV.
Chloral hydrate may be habit- forming. Patients known to be addiction- prone and patients who actively solicit hypnotics in increasing doses are potential addicts. Many patients take higher doses of hypnotics than they admit, and slurring of speech, incoordination, tremulousness, and nystagmus should arouse suspicion. Drowsiness, lethargy, and hangover are frequently observed from excessive drug intake.
Prolonged use of larger than usual therapeutic doses may result in psychic and physical dependence. Tolerance and psychologic dependence may develop by the second week of continued administration.
Chloral hydrate addicts may take huge doses of the drug (i.e., up to 12 g nightly has been reported). This abuse is similar to alcohol addiction and sudden withdrawal may result in central nervous excitation, with tremor, anxiety, hallucination, or even delirium which may be fatal. In patients suffering from chronic chloral hydrate intoxication, gastritis is common and skin eruptions may develop. Parenchymatous renal injury may also occur. Withdrawal should be undertaken in a hospital and supportive treatment similar to that used during barbiturate withdrawal is recommended.