Barbiturate dependents 88 medical

When used for detoxification, phenobarbital is given in equal doses four times a day. The maximum daily dose of phenobarbital is 600 mg, but much lower doses are usually sufficient. The phenobarbital dose is lowered (i.e., tapered) by about 20% per day. If the patient is too drowsy, then a dose should be skipped. If breakthrough withdrawal symptoms continue to occur, then the pace of the detoxification should be slowed. Before using phenobarbital, liver function tests should be obtained. All barbiturates depend greatly on the liver to be metabolized. Alcoholics with cirrhosis or other forms of liver impairment may have difficulty clearing phenobarbital. Phenobarbital should not be used in patients with poor liver function. In addition, the barbiturates can worsen a medical condition known as porphyria and should be avoided in those with this disorder. Phenobarbital, as noted, is seldom used today for alcohol detoxification. 

Dependence on barbiturates has declined in recent years as physicians have substituted benzodiazepines for the treatment of many of the conditions for which barbiturates were formerly used. Clinicians will still see cases of abuse and dependence among medical patients receiving barbiturates or barbirurate combination products (e.g., Fiorinal) and in substance abusers (Silberstein and McCrory 2001). 

Schedule III—The drug or other substance has (1) a potential for abuse less than the drugs or other substances in Schedules I and II, (2) a currently accepted medical use in treatment in the United States, and (3) abuse of the drug or other substance may lead to moderate or low physical dependence or high psychological dependence. Examples ketamine, anabolic steroids, some barbiturates. 

Many CNS depressants have some liability for dependence. This is typically greater with barbiturates, but lesser with benzodiazepines, and perhaps nonexistent in many antiseizure medications. CNS depressants produce tolerance when administered chronically, where increasingly larger doses are required to sustain the same level of effect. Further, a cross-tolerance often develops, where the tolerance is generalized to other CNS depressants. For example, a person with an ethanol tolerance will also display some tolerance to barbiturates. The therapeutic index tends to decrease as tolerance increases, so that the difference between an effective and toxic dose diminishes. Thus, tolerance to CNS depressants is accompanied by a smaller safety margin. 

Historically, the treatment of alcohol use disorders with medication has focused on the management of withdrawal from the alcohol. In recent years, medication has also been used in an attempt to prevent relapse in alcohol-dependent patients. The treatment of alcohol withdrawal, known as detoxification, by definition uses replacement medications that, like alcohol, act on the GABA receptor. These medications (i.e., barbiturates and benzodiazepines) are cross-tolerant with alcohol and therefore are useful for detoxification. By contrast, a wide variety of theoretical approaches have been used to reduce the likelihood of relapse. This includes aversion therapy and anticraving therapies using reward substitutes and interference approaches. Finally, medications to treat comorbid psychiatric illness, in particular, depression, have also been used in attempts to reduce the likelihood of relapse. 

The antipsychotics do not produce a ciassic withdrawai syndrome of the type seen with barbiturates or opioids nor do they produce psychological dependency, as seen with psychostimuiants (e.g., cocaine, amphetamine). Addicts and patients both dislike these drugs and do not spontaneously increase their dose. Indeed, they are more likely to discontinue them without medical advice. 

Schedule drugs such as barbiturates and codeine have limited medical uses and some danger for abuse and dependency but not as serious as cocaine and morphine. 

Phenobarbital, mephobarbital and metarbital are the only oral anticonvulsants which are effective at sub-hypnotic levels. Many barbiturates are classified as Schedule II, III, or IV due to their high potential for overdose and dependence. Abrupt withdrawal may cause seizures, restlessness, trembling, and insomnia and may be fatal. Phenobarbital is used as an anticonvulsant for the treatment of epilepsy and in some combination medications for the relief of irritable bowel syndrome. 

The depressant effect of barbiturates is often sought by persons who are self-medicating for amdety-related problems or insomnia. Drugs of the benzodiazepine family (Librium, Valium, and Xanax) are also legitimately prescribed for the treatment of anxiety as well as muscle spasms or convulsions. However, doctors and patients must be careful because prolonged or excessive use can lead to dependence. Illegal use often involves forged prescriptions or the cooperation of illicit doctors. 

German chemists knew in the 1900s that barbiturates could be addictive. However, people who took barbiturates did not always exhibit symptoms of drug dependence or withdrawal. By the 1940s, the addictive nature of barbiturates alarmed groups ranging from the American Medical Association (AMA) to the United States Food and Drug Administration (FDA). 

Barbiturates act so powerfully on the nervous system that a person must gradually withdraw from these drugs. To suddenly stop taking barbiturates could result in serious medical complications or death. This withdrawal process, known as detoxification, is part of the treatment process for people dependent on barbiturates. 

Schedule II drags have a high potential for abuse. They are accepted for medical use with restrictions. These drugs may lead to severe psychological or physical dependence. Barbiturates in this category are amo-barbital (Amytal), pentobarbital (Nembutal), and secobarbital (Seconal, Tuinal). 

Schedule IV drugs have a low abuse potential as compared to Schedule m drugs. These substances have an accepted medical use. They could lead to limited psychological or physical dependence, according to the CSA. The Schedule IV barbiturates are barbital (Veronel), mephobarbital (Mebaral), and phenobarbital (Luminal). Five prescription refills are allowed during the six months after the patient received the first prescription. 

Physical dependence on barbiturates can develop within a month of use, and it is extremely dangerous because of the very serious and sometimes fatal withdrawal reactions—reactions that are worse than those of morphine or heroin withdrawal. Medical supervision is necessary because suddenly stopping or rapidly decreasing the dose can result in symptoms that include delirium and severe convulsions, sometimes beginning within hours of the last dose. 

Medications are important depending on the patient s addiction. (For barbiturates, there is no drug cure.)... 

GABA (gamma- aminobutyric acid) Inhibitory. Secreted by neurons in the cerebral cortex, subcortical area, and spinal cord. Anxiety states, also involved in chemical dependency. Diffusely affected by many medications. Many antianxiety medications work on GABA receptor sites, especially in the frontal lobe of the brain. Alcohol, benzodiazepines, and barbiturates all affect GABA receptors, as do other drugs. 

Minor tranquilizers and sedative-hypnotics are widely used in general medical practice and psychiatry. Although the benzodiazepines as a class are much safer than earlier medications (there is less risk of dependency and abuse, and withdrawal symptoms are generally much less dangerous than with barbiturates), problems do exist when patients begin to reduce doses, especially if they discontinue rapidly or "cold turkey." Benzodiazepine withdrawal sjmdromes are encoimtered frequently. They cause considerable patient distress, can be dangerous at times, and are almost always avoidable if the clinician follows the discontinuation guidelines carefully. 

One major reason for the movement away from the medical use of barbiturates involves tolerance and dependence. Tolerance develops fairly rapidly to many effects of the barbiturates. Whereas a given dose may be effective at inducing sleep for a while, if the drug is used regularly the patient soon may require a higher dose in order to sleep. If doses escalate too much and regular use persists, the patient will experience an abstinence syndrome when he or she attempts to withdraw from barbiturates. The symptoms of the barbiturate withdrawal syndrome are similar to those of alcohol— shakes, perspiration, confusion, and in some cases full-blown delirium tremens (DTs) (see Chapter 9)—but convulsions and seizures are more likely to occur in barbiturate... 

Many people became dependent on barbiturates even though the drugs were used only under medical supervision. Suppose someone is in crisis—say, after the death of a spouse or other loved one. A physician may prescribe a sleeping pill to help the person rest during the crisis. After a tew weeks the patient may feel emotionally ready to sleep without the drug—and indeed may be. But the first night he or she attempts to sleep without the barbiturate, the person may have a great deal of trouble because one of the features of barbiturate withdrawal is rebound insomnia (Mendelson, 1980). That is, after the chronic use of barbiturates, abstinence produces insomnia even in someone who was untroubled with insomnia previously. 

What Schedule II medications are at high risk for abuse, and physical and psychological dependence Opioids, barbiturates, and stimulants that are not combined with other medication are at high risk for abuse, and physical and psychological dependence. 

Medications can cross the placenta and have an adverse effect on the fetus. The fetus has an immature metabolism and a slow excretion rate that can cause a pooling of the medication. Depending on the physiological effect of the medication, the fetus can be addicted to the medication and go through withdrawal after birth. This can occur with alcohol, barbiturates, and narcotics. 

Older medications, such as the barbiturates, are used as sedative-hypnotics, but toxicity limits their widespread use. For example, they can cause significant central nervous system (CNS) depression, physical dependence, and tolerance. Additionally, they are potent inducers of liver enzymes, which can lead to clinically significant drug interactions when these medications are administered with other drugs extensively metabolized by the liver. 

The drug discovery process and an understanding of structure-aotivity relationships has taken us from very toxio medications that were dangerous at high doses and caused physical dependence (i.e., barbiturates) to medioations that are safe and apparently free from any abuse liability (i.e., ramelteon). These newer medioations, brought to us by basio soience techniques, will improve the quality of life for many who suffer from insomnia. 

Schedule 11 drugs have an accepted medical use in the United States and a high rate of abuse, with either severe psychological or physical dependence potential. These drugs include morphine, codeine, cocaine, amphetamine, and most barbiturate preparations containing amobarbital, secobarbital, and pentobarbital. 

Schedule 111 drugs have an accepted medical use, but a lower potential for abuse than do Schedules I or II, and have a potential for low or moderate physical dependency or high psychological dependency. Examples are all barbiturate preparations (except phenobarbital) not covered under Schedule II, some codeine preparations, and steroid preparations, such as testosterone and its esters. 

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