Opioids

Opioids are commonly prescribed because of their analgesic or pain relieving properties. Among the drugs that fall within this class - sometimes referred to as narcotics - are morphine, codeine, methadone, and related drugs. Morphine is often used before or after surgery to alleviate severe pain. Codeine is used for milder pain. Methadone is sometimes used as a substitute for heroin, but is highly addictive in itself. Other examples of opioids include oxycodone (OxyContin-an oral, controlled release form of the drug); propoxyphene (Darvon); hydrocodone (Vicodin); hydromorphone (Dilaudid); and meperidine (Demerol).

Opioids act by attaching to specific proteins called opioid receptors, which are found in the brain, spinal cord, and gastrointestinal tract. When these drugs attach to certain opioid receptors in the brain and spinal cord they can effectively block the transmission of pain messages to the brain.

In addition to relieving pain, opioid drugs can affect regions of the brain that mediate what we perceive as pleasure, resulting in the initial euphoria that many opioids produce. They can also produce drowsiness, cause constipation, and, depending upon the amount of drug taken, depress breathing. Taking a large single dose could cause severe respiratory depression or be fatal.

Opioids may interact with other drugs such as alcohol, antihistamines, barbiturates, or benzodiazepines. These drugs slow down breathing, and their combined effects could risk life-threatening respiratory depression.

Chronic use of opioids can result in tolerance to the drugs so that higher doses must be taken to obtain the same initial effects. Long-term use also can lead to physical dependence - the body adapts to the presence of the drug and withdrawal symptoms occur if use is reduced abruptly.

Symptoms of withdrawal can include restlessness, muscle and bone pain, insomnia, diarrhea, vomiting, cold flashes with goose bumps ("cold turkey"), and involuntary leg movements.

Options for effectively treating addiction to prescription opioids are drawn from experience and research on treating heroin addiction.

CNS depressants slow down normal brain function. In higher doses, some CNS depressants can become general anesthetics.

CNS depressants can be divided into two groups, based on their chemistry and pharmacology:

• Barbiturates, such as mephobarbital (Mebaral) and pentobarbital sodium (Nembutal), which are used to treat anxiety, tension, and sleep disorders.
  
  
• Benzodiazepines, such as diazepam (Valium), chlordiazepoxide HCl (Librium), and alprazolam (Xanax), which can be prescribed to treat anxiety, acute stress reactions, and panic attacks. Benzodiazepines that have a more sedating effect, such as triazolam (Halcion) and estazolam (ProSom) can be prescriped for short-term treatment of sleep disorders.
  
  

There are many CNS depressants, and most act on the brain similarly - they affect the neurotransmitter gamma-aminobutyric acid (GABA). Neurotransmitters are brain chemicals that facilitate communication between brain cells. GABA works by decreasing brain activity. Although different classes of CNS depressants work in unique ways, ultimately it is their ability to increase GABA activity that produces a drowsy or calming effect. Barbiturates and benzodiazepines can be addictive

CNS depressants should not be combined with any medication or substance that causes sleepiness, including prescription pain medicines, certain over-the-counter cold and allergy medications, or alcohol. The effects of the drugs can combine to slow breathing, or slow both the heart and respiration, which can be fatal.

Discontinuing prolonged use of high doses of CNS depressants can lead to withdrawal. Because they work by slowing the brain's activity, a potential consequence of abuse is that when one stops taking a CNS depressant the brain's activity can rebound to the point that seizures can occur. Someone thinking about ending their use of a CNS depressant, or who has stopped and is suffering withdrawal, should speak with a physician and seek medical treatment.

In addition to medical supervision, counseling in an in-patient or out-patient setting can help people who are overcoming addiction to CNS depressants. For example, cognitive-behavioral therapy has been used successfully to help individuals in treatment for abuse of benzodiazepines.

Often the abuse of CNS depressants occurs in conjunction with the abuse of another substance or drug, such as alcohol or cocaine. In these cases of polydrug abuse, the treatment approach needs to address the multiple addictions.

Stimulants are a class of drugs that cause an increase in blood pressure, heart rate, and respiration.

Historically, stimulants were used to treat asthma and other respiratory problems, obesity, neurological disorders, and a variety of other ailments. As their potential for abuse and addiction became apparent, the use of stimulants began to wane.

Stimulants such as dextroamphetamine (Dexedrine) and methylphenidate (Ritalin) have chemical structures that are similar to key brain neurotransmitters called monoamines, which include norepinephrine and dopamine. Stimulants increase the levels of these chemicals in the brain and body. This, in turn, increases blood pressure and heart rate, constricts blood vessels, increases blood glucose, and opens up the pathways of the respiratory system.

The consequences of stimulant abuse can be extremely dangerous. Taking high doses of a stimulant can result in an irregular heartbeat, dangerously high body temperatures, and/or the potential for cardiovascular failure or lethal seizures. Taking high doses of some stimulants repeatedly over a short period of time can lead to hostility or feelings of paranoia in some individuals.

Treatment of addiction to prescription stimulants, such as methylphenidate and amphetamines, is based on behavioral therapies proven effective for treating cocaine or methamphetamine addiction.