Barbiturates: Usage, History, and Side Effects

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What is the most important information I should know about barbiturates?

Barbiturates are not often prescribed due to the: 

  • high risk for tolerance, dependence, and severe withdrawal symptoms; and 
  • high risk for overdose.

Never combine barbiturates with other depressant medications, including alcohol, and call 911 immediately if you suspect an overdose.

Barbiturates are substances that have sedative-hypnotic effects. These drugs are sometimes prescribed to help reduce anxiety and induce sleep, but they can also be dangerous and habit-forming. 

This article discusses what barbiturates are, how they work, and their potential side effects. It also covers potential side effects and risks of withdrawal.

What Are Barbiturates?

Barbiturates are a class of drugs derived from barbituric acid that act as depressants to the central nervous system. These drugs are used as sedatives or anesthetics and have the potential to become addictive. They're problematic because there is no good treatment to reverse a barbiturate overdose. 

Barbiturates have been used for physician-assisted suicide (in states where such procedures are legal).

Key Facts About Barbiturates

Drug class: Sedative-hypnotic

Effects: Causes drowsiness, relaxation, lack of inhibition, and impaired memory

Risks: Leads to tolerance quickly and can easily lead to a potentially fatal overdose

History of Barbiturates

German researcher Adolph von Baeyer was the first to synthesize barbituric acid. Barbital (Veronal) was the first barbiturate and was used for medical purposes in 1903. Barbiturates were frequently used to treat agitation, anxiety, and insomnia, but their use for treating such symptoms fell out of favor due to the risk of overdose and abuse.

Legend suggests that the drug's name comes from the date Baeyer and his colleagues discovered it. They went to celebrate their find at a tavern on the feast day of St. Barbara.

Barbiturates became popular during the 1960s and 1970s in treating seizures, sleep problems, and anxiety. Their use for recreational purposes also increased during this period.

The use of barbiturates declined after the introduction of benzodiazepines. However, barbiturates are still used for some medical purposes.

Benzodiazepines have largely replaced barbiturates in most medical uses.

Common Barbiturates

There are a number of different types of drugs that are considered barbiturates. Some of the most common include:

Amobarbital

Commonly referred to as "sodium amytal," this barbiturate gained a reputation as a truth serum since it proved effective when given to some subjects during interrogation. While it doesn't compel people to tell the truth, amobarbital can slow the central nervous system, making concentration more difficult.

The theory was that someone asked a question while under the influence of amobarbital would be less likely to be able to think of a false answer, which requires more focus than simply telling the truth.

Butalbital

This short-acting barbiturate is frequently used to treat migraine headaches, often combined with acetaminophen, aspirin, and caffeine. It was marketed under the brand names Fiorinal and Fioricet. It's also been used as a sedative and an anesthetic.

Phenobarbital

This barbiturate was used to treat seizures in young children due to its effectiveness as an anticonvulsant. It has also been used to treat anxiety, drug withdrawal (particularly from other barbiturates), and sleep aid.

Secobarbital

First marketed in the U.S. as Seconal started in 1934, this drug was a widely-prescribed sleep aid. It's the most-used drug in physician-assisted suicides in the U.S.

Pentobarbital

Used as an anesthetic in animals, this drug formerly used to treat seizures and convulsions has the dubious distinction of being one of the preferred drugs used for state executions in the U.S.

Effects of Barbiturates

The pharmacological actions of barbiturates include depressing nerve activity in the cardiac, smooth, and skeletal muscles. These drugs also affect the CNS in several ways and can produce effects ranging from mild sedation to a coma depending on the dosage.

Low doses of barbiturates can lower anxiety levels and relieve tension. Higher doses can decrease the heart rate and blood pressure.

Barbiturates have some severe drawbacks, including:

  • Potentially dangerous interactions with other drugs
  • Lack of safety and selectivity
  • A tendency to create dependence, tolerance, abuse, and withdrawal
  • Lack of effective treatment for overdoses

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area.

For more mental health resources, see our National Helpline Database.

Side Effects of Barbiturates

At prescribed doses, barbiturates can cause relaxation and drowsiness. However, they can also have side effects, which may include:

  • Confusion
  • Headache
  • Impaired memory
  • Lack of inhibition
  • Poor coordination
  • Respiratory arrest

Barbiturates also easily produce tolerance, meaning it takes more of the drug to produce the same effects. Overdose can happen easily. Signs of a barbiturate overdose include clammy skin, dilated pupils, shallow respiration, rapid and weak pulse, and coma. 

If you suspect that someone has overdosed on barbiturates, seek medical attention immediately.

Withdrawal Symptoms

Because barbiturates are habit-forming, stopping their use can cause withdrawal symptoms. Some symptoms that a person might experience include:

  • Anxiety
  • Hallucinations
  • Nausea
  • Restlessness
  • Seizures
  • Suicidal thoughts
  • Stomach upset
  • Vomiting

Talk to your doctor before you stop taking barbiturates. Your doctor may gradually lower your dose over a period of time to minimize dangerous withdrawal complications.

Frequently Asked Questions

  • What do barbiturates do?

    Barbiturates work by increasing the amount of gamma-aminobutyric acid (GABA) in the brain. GABA is an inhibitory neurotransmitter, so increasing its levels reduces nerve transmission. Because of this action, barbiturates can induce sleep, prevent seizures, reduce anxiety, and relieve muscle spasms.

  • How long do barbiturates stay in your system?

    Different types of barbiturates stay in the body for different lengths of time. Short-acting barbiturates have a shorter half-life and are eliminated faster. Longer-acting ones have a longer half-life and stay in the body longer. Understanding how long barbiturates stay in the body can help people avoid dangerous drug interactions and overdoses.

  • Which class of drugs are barbiturates?

    Barbiturates belong to the sedative-hypnotic drug class. Sedative hypnotics are drugs used to induce and/or maintain sleep.

  • What drugs interact with Barbiturates?

    Other drugs that can interact with barbiturates include alcohol, anticoagulant medications, corticosteroids, sedatives, hypnotics, CNS depressants, and monoamine oxidase inhibitors (MAOIs). Always tell your doctor about any medications, substances, or supplements you are taking before taking barbiturates or any other medications.

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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kendra Cherry, MSEd
Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."