Differences Distinguishing the Benzodiazepines From One Another
The first difference is the half-life, or the amount of time the drugs circulate in the body before they are eliminated. The longer the half-life, the longer the medication stays in the body. Librium has a very long half-life relative to Ativan, and for that reason, it is generally preferred, as there is less chance of having symptoms return due to a missed dose. The second difference is how the drug is metabolized for elimination from the body. Some drugs are metabolized by that part of the liver affected by hepatitis and cirrhosis. Under those circumstances, the liver cannot effectively metabolize the drug fast enough, and it can build up to toxic levels in the body. For that reason, Ativan has generally supplanted Librium for patients hospitalized for DTs because the majority of these patients have liver impairment. The third difference is the route of administration. The more routes of administration that are available, the more flexible the medication is in its administration, thus allowing for continued use even when the patient is unable to take oral medication for a variety of reasons. Ativan, for example, can be given orally, intravenously, or intramuscularly; Librium can only be given orally. Ativan is preferred in the hospital setting as a result of its flexibility in addition to its safety.
Half-life the time it takes for half of the blood concentration of a medication to be eliminated from the body. The half-life determines the time to achieve equilibrium of a drug In the blood and determines the frequency of dosing to maintain that equilibrium.
Although most of the evidence favors the use of benzodiazepines in the treatment of alcohol withdrawal syndromes, detractors do exist. Some physicians prefer the use of anticonvulsants, many of which also target GABA, although in a less direct manner than the benzodiazepines. Their opposition to benzodiazepine use for detoxification is based on a variety of concerns, not the least of which is the idea that benzodiazepines may actually "prime" alcoholics to start drinking again. At least one study compared patients receiving Ativan with those receiving the anticonvulsant carbamazepine (Tegretol). In this study, both drugs were equally effective in managing the withdrawal symptoms, although Ativan was superior in managing anxiety and insomnia. However, the Ativan treatment group had a greater risk of rebound of alcohol withdrawal symptoms after cessation of treatment. Additionally, their risk of having a first drink was three times greater. Finally, with respect to outpatient detox, there is a risk that the patient will drink on top of the benzodiazepine, which places them at even greater risk for alcohol poisoning. Despite this one study and its concerns, benzodiazepines remain the standard of care in the United States.
Other medications have also been used to manage alcohol withdrawal symptoms, but these are used primarily as adjuncts and not alternatives to a benzodiazepine. Propanolol (or Inderal), a beta-blocker, is an antihypertensive medication that can lower blood pressure and slow the heart rate in these patients.
Haloperidol (Haldol), an antipsychotic medication, is occasionally used for severe agitation and psychotic symptoms such as delusions and hallucinations in some patients, although there is a small risk of causing a seizure. Phenytoin (Dilantin), an anticonvulsant, is the most commonly recommended medication for alcohol withdrawal seizures. Alcohol seizures are discussed further in Question 65. Finally, multivitamins, thiamine, and folate are routinely administered because of the high incidence of vitamin deficiencies that accompany alcoholism.