Substance abuse barbiturates

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). 

Eighty-three patients provided concentration-time data. Exclusion criteria included elevated transaminases, bilirubin, or serum creatinine decreased neutrophils, hemoglobin, or platelet counts malabsorption syndrome opportunistic infections alcohol, narcotics, barbiturates, cocaine, or other CNS-active substance abuse hypersensitivity to any of the protocol mandated drugs patients of childbearing potential who were unwilling to use an effective method of contraception and concomitant medications interfering with human cytochrome P450 system. 

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. 

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. 

Schedule IV Substances with low abuse potential for example, some barbiturate compounds, chloral hydrate, and benzodiazepine derivatives. 

With barbiturates less available, drug abusers turned to other illegal substances during the 1970s and 1980s. One indication of drug demand was the record of... 

Passage of the federal Controlled Substances Act in 1970 restricted access to barbiturates. That action led to an eventual decline in the use and abuse of one of the most widely prescribed drugs of the twentieth century. 

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. 

Glutethimide (Doriden), a highly lipid-soluble drug classified as a sedative-hypnotic, was introduced in 1954 as a safe barbiturate substitute. However, its addiction potential and the severity of withdrawal symptoms were similar to those of barbiturates. In 1991, glutethimide was classified as a Schedule II controlled substance in response to an upsurge in the prevalence of diversion, abuse, and overdose deaths. The drug is illegal in the United States and in several other countries. It is classified as a sedative-hypnotic. 

By 1972, luding out —taking methaqualone with wine—was popular on college campuses. Excessive use of the drug leads to tolerance, dependence, and withdrawal symptoms similar to those of barbiturates. Overdose by methaqualone is more difficult to treat than barbiturate overdose, and deaths have frequently occurred. In the United States, the marketing of methaqualone pharmaceutical products was discontinued in 1984, and the drug became a Schedule I controlled substance. However, some level of occasional abuse has continued. 

All barbiturates have the potential to be abused and cause addiction. Different barbiturates are designated as schedule II, III, and IV drugs, which means that all barbiturates require a prescription from a doctor or health care provider and the prescription must contain the doctor s DEA number. Physicians must obtain a special license to get a DEA number in order to prescribe controlled or addictive substances such as barbiturates. Doctors are very cautious about prescribing barbiturates to patients who have a history of drug abuse. 

Table 29 shows the reported use of selected substances of potential abuse. Most frequently reported was marijuana (37% of respondents), followed by "other nartotics, opiates" (34%), tranquilizers (29%), amphetamines and other stimulants (18%), LSD (12%), barbiturates and other depressants (10%), cocaine (10%), phencyclidine (3%), and heroin (2%). 

Fetal microcephaly has been attributed to cocaine abuse during pregnancy (323). Urine toxicology confirmed the presence of morphine, benzoylecgonine, barbiturates, paracetamol, and propoxyphene. Analyses of amniotic fluid, placenta, and fetal serum and urine were also positive for these substances. The authors suggested that vascular disruption was the likely major mechanism of anomalies, both behavioral and malformative, due to prolonged exposure to cocaine in utero. 

Ramelteon is a melatonin receptor agonist selective for the MTj and MT2 receptors. The dose is 8 mg at bedtime. It is well tolerated, but side effects include headache, dizziness, and somnolence. It is not a controlled substance. Zolpidem, chemically unrelated to benzodiazepines or barbiturates, acts selectively at the y-aminobutyric acid (GABA )-receptor and has minimal anxiolytic and no muscle relaxant or anticonvulsant effects. It is comparable in effectiveness to benzodiazepine hypnotics, and it has htde effect on sleep stages. Its duration is approximately 6 to 8 hours, and it is metabolized to inactive metabolites. Common side effects are drowsiness, amnesia, dizziness, headache, and GI complaints. Rebound effects when discontinued and tolerance with prolonged use are minimal, but theoretical concerns about abuse exist. It appears to have minimal effects on next-day psychomotor performance. The usual dose is 10 mg (5 mg in the elderly or those with liver impairment), which can be increased up to 20 mg nightly. Cases of psychotic reactions and sleep-eating have been reported. 

Barbiturates and alcohol both increase the activity of (induce) the enzymes that metabolize paracetamol to the toxic product. A chronic alcohohc or someone who has been prescribed barbiturate drugs will be at greater risk when taking more than the recommended dose of paracetamol because a greater proportion of the dose will be converted into the toxic product. It would be equivalent to taking a larger dose. In the case of an alcoholic the liver may already be compromised by repeated and long-term alcohol abuse and so be more vulnerable and less able to detoxify paracetamol it may also have less protective substances like thiols. 

Barbiturates are derivatives of barbituric acid. These substances were once used extensively in clinical practices as sedatives-hynotics. Because of their abuse and physical dependence, their therapeutic application has diminished considerably. The sedative effects of barbiturates are similar to those of alcohol. Higher dosage can cause hypnosis and anesthesia. An intake of barbiturates 10-15 times that of the hypnotic dose can be toxic. Coma and death can result from overdose. 

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