Central nervous system drug abuse

Many simple molecules have profound effects on the central nervous system. Several of these are drugs of abuse methamphetamine, cocaine, and heroin, among others. 

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. 

Each neuron has specific synthetic machinery that enables it to both synthesize and eliminate a specific neurotransmitter. For example, neurons of the sympathetic nervous system employ norepinephrine and epinephrine as their transmitters. Other neurons, particularly in the central nervous system, employ dopamine as their transmitter. Dopamine is a particularly important transmitter for a variety of neuronal functions. Its loss is associated with Parkinson disease, and it is a critical agent in the mediation of pleasure and reward processes. Dopamine, due to its association with pleasurable sensations, is widely implicated in the actions of a number of drugs of abuse, including cocaine, opiates, and methamphetamines. 

In the central nervous system, there are close associations between NT and dopamine systems, and NT may be involved in clinical disorders involving dopamine pathways such as schizophrenia, Parkinson s disease, and drug abuse. Consistent with this, it has been shown that central administration of NT produces effects in rodents similar to those produced by antipsychotic drugs. 

The most commonly abused prescription drugs are opioids and opiates such as oxycodone and morphine, central nervous system depressants such as barbiturates and benzodiazepines, and stimulants such as dextroamphetamine and methylphenidate. Brand-name painkillers such as Vicodin and OxyContin, depressants such as Valium and Xanax, and stimulants such as Ritalin and Dexedrine are commonly abused (as are some OTC cough remedies). Although helpful and safe when used appropriately, these drugs can cause serious harm when taken in unapproved ways. 

As we will see in part V, the Recreational Drugstore, many of the abused stimulant drugs that cause seizures during acute use are highly sleep suppressant through their direct action on neuromodulatory systems. Alcohol, by contrast, is a general central nervous system suppressant. As such, and in contrast to the stimulants, alcohol causes euphoria only as a relatively brief consequence of its essentially anesthetic action on the brain. By numbing the brain it induces relaxation, lifts cortical inhibition, and produces a temporary sense of comfort with the self and with society. 

If, at the time a new-drug application is submitted to the Secretary for any drug having a stimulant, depressant, or hallucinogenic effect on the central nervous system, it appears that such drug has an abuse potential, such information shall be forwarded by the Secretary to the Attorney General. 

AMPHETAMINES. Amphetamines, used in medicine as central nervous system (CNS) stimulants, are among the most commonly abused drugs. Amphetamine itself is chemically di-a-methylphenethyl-amine, the most common commercial name being Benzedrine, nicknamed "Bennie." Other commonly encountered amphetamines in urine... 

Dextroamphetamines are a part of the amphetamine class of drugs, central nervous system (CNS) stimulants that are used in the treatment of certain brain-based disorders. Because of their long-lasting and potent stimulant effects, they are also highly physically and psychologically addictive and have a high rate of abuse. 

Dizziness may occur in a small proportion of cases when dextromethorphan is used therapeutically. Mental confusion and central nervous system overstimulation may occur when there is an overdose of the drug. When dextromethorphan is abused, there is an increased risk of motor impairment that could affect activities that require quick judgment and reaction, such as operating heavy machinery. 

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