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Substance Abuse and Addiction Health Center

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Prescription Drug Abuse

How Do Opioids Work on the Brain and Body? continued...

When they're taken as prescribed, opioids and other painkillers manage pain quite effectively. They can improve quality of life for people with chronic pain. In fact, using opioids for the short-term or under a doctor's cautious supervision rarely leads to addiction or dependence. However, when used long-term, opioids may lead to drug abuse with physical dependence and/or addiction. Opioids can also be life threatening in an overdose. When they are taken with substances that depress the central nervous system -- including alcohol, barbiturates, or benzodiazepines such as alprazolam (Xanax), clonazepam (Klonopin), or diazepam (Valium) -- there is a greatly increased risk of respiratory depression, even death.

Opioids induce a euphoric feeling that's usually mild. However, opioids such as OxyContin are sometimes inappropriately snorted or injected to increase the euphoric effects.


How Do CNS Depressants Work on the Brain and Body?

Benzodiazepines depress the central nervous system (CNS). They are used by millions in the U.S. to treat anxiety and sleep disorders, including insomnia. These CNS depressants affect the brain neurotransmitter GABA (gamma-aminobutyric acid). GABA works by decreasing brain activity, which results in a drowsy or calming effect.

Barbiturates, including amobarbital (Amytal), pentobarbital (Nembutal), phenobarbital (Luminal), and secobarbital (Seconal), are also CNS depressants. They are commonly used for anesthesia and are prescribed to treat seizures and, occasionally, insomnia or anxiety on a short-term basis.

Taking CNS depressants for a few days to a few weeks may help you feel calm and sleepy. After a while, however, you may need larger doses to get the same calm and sleepy feeling. In addition, using CNS depressants with alcohol can slow down your heart and breathing and lead to death.

After taking CNS depressants for a long period of time, stopping suddenly can have life-threatening consequences such as withdrawal seizures.

How Do Stimulants Work on the Brain and Body?

Stimulants give your body a fast jumpstart, causing a great increase in alertness, energy, and attention. Stimulants increase heart rate, blood sugar, and blood pressure, constrict blood vessels, and open the pathways of the respiratory system.

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