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A barbiturate is a type of medication that has been around for over 150 years. Barbiturates were popular from the early 1900s through the 1970s. Two of the most common uses were for sleep and anxiety.

Barbiturates have a depressant effect on the brain. They increase the activity of gamma aminobutyric acid (GABA), a brain chemical that creates a sedating effect.

They can have short- to long-acting effects. It depends on the specific drug.

Barbiturates are habit-forming. You can develop a tolerance to and dependence on them. This means you need greater amounts to get the same effect. In addition, abruptly stopping this type of medication causes withdrawal symptoms.

Taking higher doses of barbiturates is dangerous because you can overdose. This is one of the reasons these medications aren’t prescribed as much now.

Read on to learn more about barbiturate uses, effects, and risks.

Today, barbiturates are used for:

They’re also used as anesthetic drugs.

Barbiturates are available in injectable, liquid, tablet, and capsule forms. They come in many different strengths and combinations.

The most common barbiturates are listed below.

Generic nameBrand nameDosage in milligrams (mg) per day
MethohexitalBrevitalVaries
PentobarbitalNembutal150–200 mg via intramuscular injection; 100 mg via intravenous injection
PhenobarbitalOnly available as a generic30–120 mg for sedation; 60–200 mg for anticonvulsant use in adults; 3–6 mg/kilograms of body weight for anticonvulsant use in children (all via oral solution)
PrimidoneMysoline750–1,000 mg in divided doses for people 8 years old and up; 10–25 mg/kg of body weight in divided doses for children under 8 years old (via tablet)

[This is the maintenance dosage you will take beginning on day 10 of your regimen. Dosages on days 1 through 9 will be lower.]

The barbiturate butalbital is also an ingredient in these combination products used to help treat headaches:

  • butalbital-acetaminophen (Allzital, Butapap)
  • butalbital-acetaminophen-caffeine
  • butalbital-acetaminophen-caffeine-codeine (Fioricet with codeine)
  • butalbital-aspirin-caffeine (Fiorinal, Lanorinal)
  • butalbital-aspirin-caffeine-codeine (Fiorinal with codeine)

The most common side effects of barbiturates are dizziness and drowsiness. Tasks that require you to be alert, such as driving, might be challenging.

Some side effects are rare but very serious. These include:

Call a healthcare professional right away if you experience any of these side effects.

Other possible side effects include:

Talk with a healthcare professional if you have any concerns about side effects.

Barbiturates have limited use today because newer drugs, such as benzodiazepines, have a much better safety record.

The risks of barbiturates are greater than their benefits. People prescribed these drugs must be carefully monitored to avoid side effects.

Certain factors can increase the risk of barbiturate side effects or overdose. This includes age, health conditions, and any other medications you’re taking.

Barbiturates can add to the sedating effects of alcohol and other medications. These medications include:

Effect on pregnancy

Barbiturates are sometimes used during pregnancy if other medication options are unavailable. There are risks linked to barbiturate use during pregnancy.

Many older studies have established a link between barbiturate use during pregnancy and congenital abnormalities. Babies may have complications with growth and development if exposed to barbiturates long term during pregnancy.

Babies can also be born dependent on barbiturates and experience withdrawal symptoms after birth.

A 2011 study found that exposure to the barbiturate pentobarbital in newborn rats caused problems with brain development. The drug affected learning, memory, and other important functions.

Withdrawal symptoms

You cannot suddenly stop taking barbiturates after regular use. It can trigger severe withdrawal symptoms, including the risk of death.

Reaction severity depends on:

  • a person’s overall health
  • other health conditions they may have
  • other medications they take

If you’ve been taking a barbiturate, talk with a doctor before stopping the medication.

Some withdrawal symptoms include:

For serious withdrawal symptoms, you may need to be monitored in the hospital until the drug’s out of your body. This could take several days.

Barbiturates can interact with the following:

Most drug interactions involving barbiturates were observed in people taking phenobarbital. However, experts believe that other barbiturates can potentially interact with the same medications as phenobarbital.

Taking barbiturates while taking these medications or consuming alcohol may make the medications less effective or cause other issues. Before taking barbiturates, speak with a doctor or pharmacist about possible drug interactions.

Barbiturates are rarely used in the United States because they have a high risk of tolerance, dependence, and overdose.

Barbiturates are a Drug Enforcement Administration (DEA) controlled substance because of their potential for misuse.

The DEA classifies drugs into five drug schedule categories, ranging from Schedule I to Schedule V. The schedule number indicates the likelihood the substance could be misused as well as the drug’s accepted medical use.

For example, Schedule I drugs have no currently accepted medical use and a high potential for misuse. Schedule V drugs have a low potential for misuse.

Schedule II drugs include pentobarbital (Nembutal). Schedule IV drugs include methohexital (Brevital) and phenobarbital.

Primidone (Mysoline) is metabolized to, or processed by the body as, phenobarbital. However, it’s used for seizure disorders and has no DEA Schedule.

It’s illegal to buy or use barbiturates without a doctor’s prescription. There are federal and state penalties for buying, selling, or taking the drugs illegally.

Illegal use has resulted in overdose deaths because barbiturates are dangerous when used for self-treatment. The danger increases when they’re combined with substances such as alcohol, opioids, or benzodiazepines such as diazepam (Valium).

Online purchases are just one illegal source of barbiturates. Drugs purchased online come with greater risk because they may be contaminated with other substances or expired.

Did you know?

Barbiturates are still used in many other countries because they’re less expensive. They’re also available through laboratories (for research purposes) and veterinary sources.

Barbiturates have a poor safety record when it comes to overdoses. Many factors contribute to why someone may be vulnerable to an overdose.

They include:

  • other medications that have depressant effects on the brain, such as opioids and benzodiazepines
  • alcohol, which can slow the removal of the drug and cause a buildup in the body
  • a history of depression, suicidal thoughts, or mental health conditions
  • a history of substance use disorder
  • breathing problems, such as asthma, lung disease, and emphysema
  • heart problems
  • kidney or liver problems, which can cause the drug to build up in the body
  • age, which can affect vulnerability to side effects

There may be other reasons that cause a strong reaction to barbiturates. Be sure to discuss your medication and health history with your doctor.

Symptoms of an overdose

Call 911 or your local emergency services right away if you or someone you know has taken too much of a barbiturate or if you notice these symptoms of a drug overdose:

There’s no reversal drug for the treatment of barbiturate overdose.

Activated charcoal may be used to remove the excess drug from the body. Other measures include maintaining the airway, circulation, and breathing.

Barbiturates became popular when there were few medication options to treat seizures, anxiety, and insomnia.

Doctors stopped prescribing them widely when misuse and overdoses increased over time. Barbiturates have limited use today, and safer medications are available.

However, barbiturates are still being misused today. The risk of overdose death increases when barbiturates are used in combination with alcohol, opioids, benzodiazepines, or other medications.

Barbiturates need strict monitoring because of the risk of overdose, and they should never be used without a doctor’s supervision.