Downers are a group of drugs that all have similar sedating qualities. The word downer is an umbrella term that includes benzodiazapines, barbiturates, and alcohol. Downers are also sometimes referred to as tranquilizers, hypnotic sedatives, or depressants. Because of the widespread social use of alcohol, it is often considered its own class of drug.
The common denominator for downers is their effect on the neurotransmitter gamma-aminobutyric acid, or GABA. GABA is responsible for calming the central nervous system, slowing heart rate, breathing, and inducing sleep. Effectively, it works to counter the effects of the neurotransmitter norepinephrine, and the two work in conjunction to maintain proper heart rate, and alertness. Too much norepinephrine can lead to a number of anxiety disorders and can be responsible for ‘panic attacks’, and so downers are often prescribed to treat these conditions.
Narcotics and opiate based pain killers are sometimes lumped together with downers. While opiates do produce a sedating effect on the body, they do not directly effect the neurotransmitter GABA and are therefore a different class of drugs.
The most commonly prescribed downers today are the benzodiazapines, sometimes called benzos. The more popular benzodiazapines include diazepam (Valium), chlordiazepoxide (Librium), alprazolam (Xanax), lorazepam (Ativan), and clonazepam (Klonopin). These drugs are most commonly prescribe for anxiety disorders, but also find uses in preventing seizures, and as muscle relaxants.
Barbiturates were popularly used medically prior to the discovery of benzodiazapines in the 1950s. Barbiturates are chemicals derived from the chemical barbituric acid. The most common barbiturates include phenobarbital, pentobarbital, secobarbital, butalbital, butabarbital and sodium thiopental. Barbiturates are considerably more toxic than benzodiazapines, and have a much lower therapeutic index. A therapeutic index is the range between the minimally effective therapeutic dose and the lethal dose of the substance. A narrow index means that a lethal dose of the drug is not much more than the recommended dosage, and the drug is therefore risky. For these reasons, benzodiazapines have largely replaced barbiturates for use as medications. Barbiturates are still found in several pain medications, and find use as general anesthetics.
Downers all have a high potential for abuse, and are extremely addictive chemicals. As a class of drugs that includes alcohol, they are by far the most widely abused drugs on the planet. Even without alcohol, they rank amongst the most abused and addictive prescription drugs. Because of their high therapeutic index and low toxicity, benzodiazapines are especially easy to develop a physical dependence on. All downers, including alcohol, have very serious withdrawal symptoms, and should not be discontinued from everyday use without consulting a physician or medical professional first.