Anxiety disorders barbiturates

Substance-Induced Anxiety Disorder. Numerous medicines and drugs of abuse can produce panic attacks. Panic attacks can be triggered by central nervous system stimulants such as cocaine, methamphetamine, caffeine, over-the-counter herbal stimulants such as ephedra, or any of the medications commonly used to treat narcolepsy and ADHD, including psychostimulants and modafinil. Thyroid supplementation with thyroxine (Synthroid) or triiodothyronine (Cytomel) can rarely produce panic attacks. Abrupt withdrawal from central nervous system depressants such as alcohol, barbiturates, and benzodiazepines can cause panic attacks as well. This can be especially problematic with short-acting benzodiazepines such as alprazolam (Xanax), which is an effective treatment for panic disorder but which has been associated with between dose withdrawal symptoms. 

Benzodiazepines. Safer than the barbiturates but acting in a similar manner, the benzodiazepines have largely replaced barbiturates since their introduction in the 1960s. Other uses of benzodiazepines include treatment for epilepsy, alcohol withdrawal, several anxiety disorders, agitation, and impulsivity, as muscle relaxants, and as conscious sedation during certain medical procedures. 

Despite their beneficial effects for people suffering from anxiety or sleep disorders, barbiturates and benzodiazepines can be addictive and should be used only as prescribed. 

Benzodiazepines or barbiturates are helpful in the h eatment and prevention of seizures, and modulation of GABA receptors is beneficial in the treatment of anxiety disorders, insomnia and agitation—most likely due to a general inhibition of neuronal activity. 

Because of the lack of dependency and tolerable adverse effect profile, antidepressants have emerged as the treatment of choice for the long-term management of chronic anxiety, especially in the presence of comorbid depressive symptoms. Buspirone is an additional anxiolytic option (Table 69-7) in patients without comorbid depression or other anxiety disorders (e.g., panic disorder and SAD). Because of the high risk of adverse effects and toxicity, barbiturates, antipsychotics, antipsychotic-antidepressant combinations, and antihistamines generally are not indicated in the treatment of GAD. The benzodiazepines are more effective in treating the somatic and autonomic symptoms of GAD as opposed to the psychic symptoms (e.g., apprehension and worry), which are reduced by antidepressants. ... 

Pharmacological Profiles of Anxiolytics and Sedative—Hypnotics. Historically, chemotherapy of anxiety and sleep disorders rehed on a wide variety of natural products such as opiates, alcohol, cannabis, and kawa pyrones. Use of various bromides and chloral derivatives ia these medical iadications enjoyed considerable popularity early ia the twentieth century. Upon the discovery of barbiturates, numerous synthetic compounds rapidly became available for the treatment of anxiety and insomnia. As of this writing barbiturates are ia use primarily as iajectable general anesthetics (qv) and as antiepileptics. These agents have been largely replaced as treatment for anxiety and sleep disorders. 

Barbiturates. The first barbiturate, barbital, was introduced at the turn of the 20th century. Hundreds of others, including phenobarbital and pentobarbital, were later developed. The barbiturates were a highly successful class of medications as it became clear that they treated not only alcohol withdrawal but seizure disorders, anxiety, and insomnia as well. By the 1960s, however, the barbiturates were largely surpassed by the benzodiazepines. The newer benzodiazepines act in a similar fashion and provide much the same therapeutic benefit but are significantly safer and easier to tolerate. 

Diazepam (Valium, Diastat) [C-IVj [Anxiolytic, Skeletal Muscle Relaxant, Anticonvulsant, Sedative/Hypnotic/ Benzodiazepine] Uses Anxiety, EtOH withdrawal, muscle spasm, status epilepticus, panic disorders, amnesia, preprocedure sedation Action Benzodiazepine Dose Adults. Status epilepticus 5-10 mg IV/IM Anxiety 2-5 mg IM/IV Preprocedure 5-10 mg IV just prior to procedure Peds. Status epilepticus 0.5-2 mg IV/IM Sedation 0.2-0.5 mg/kg IV (onset w/in 5IV and 30 min IM duration about 1 h IV and IM) Caution [D, / -] Contra Coma, CNS depression, resp d es-sion, NAG, severe uncontrolled pain, PRG Disp Tabs 2, 5, 10 mg soln 1, 5 mg/mL inj 5 mg/mL rectal gel 2.5, 5, 10, 20 mg/mL SE Sedation, amnesia, bradycardia, i BP, rash, X resp rate Interactions T Effects W/ antihistamines, azole antifungals, BBs, CNS depressants, cimetidine, ciprofloxin, disulfiram, INH, OCP, omeprazole, phenytoin, valproic acid, verapamil, EtOH, kava kava, valman T effects OF digoxin, diuretics X effects w/ barbiturates, carbamazepine. 

Long-acting barbiturates include phenobarbital (Luminal) and mephobarbital (Mebaral). These drugs, which take effect in about one hour and last for about 12 hours, are used primarily for daytime sedation and the treatment of seizure disorders or mild anxiety. Generally, these are not drugs of abuse rather the short- and intermediate-acting barbiturates—such as amobarbital (Amytal), pentobarbital (Nembutal), and secobarbital (Seconal)—are among those most commonly abused. 

Barbiturates such as mephobarbital (Mebaral) and pentobarbital (Nembutal), although not prescribed as often as the BZDs, may be used to treat anxiety, tension, and sleep disorders. Veterinarians also use pentobarbital (Nembutal) for anesthesia and euthanasia. In some states, a form of barbiturate is used to execute criminals by lethal injection. 

The barbiturates and meprobamate have been entirely superseded by the benzodiazepines and because of their low benefit-to-risk ratio (dependence producing, lethality in overdose, potent sedative effects) they should never be used as anxiolytics. Despite their popularity as short-term sedatives, antihistamines are ineffective anxiolytics, while the use of sedative antidepressants such as amitriptyline should be limited to the treatment of patients with symptoms of both anxiety and depression due to their limited efficacy and the poor patient compliance associated with their adverse effects. However, patients with panic disorder do appear to show a beneficial response to antidepressants (see Chapter 6). A similar argument... 

Patients with mild symptoms of alcohol withdrawal do not generally require medication therapy. Benzodiazepines, like diazepam or alprazolam, are the treatment of choice for patients with severe alcohol withdrawal syndromes like delirium tremens. Barbiturates can also be used for this disorder, but are often less prescribed because they are not as safe as benzodiazepines. Both barbiturates and benzodiazepines are effective in treating the anxiety, tremor, insomnia, and hand tremors associated with delirium tremens. 

The problems of abuse with methaqualone and other nonbarbiturate sedatives far outweigh their medical benefits, and currently these drugs are rarely used for the management of sleep problems or anxiety. In fact, methaqualone has become a Schedule 1 drug and is no longer produced for medical use. A major reason these drugs and the barbiturates have lost favor is the widespread acceptance of the benzodiazepines as the treatment of choice in these disorders. 

Barbiturates are often referred to as "downers." Barbiturates are derived from amides and are used as sedatives. They are also used as anticonvulsants for epileptics and for people suffering from a variety of brain disorders that manifest themselves in neurosis, anxiety, and tension. 

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