Barbiturates

Barbiturates are central nervous depressants. They reduce the activity of nerves causing muscle relaxation. They can reduce heart rate, breathing, and blood pressure. All barbiturates affect gamma-aminobutyric acid (GABA), a neurotransmitter (chemical) that nerves use to communicate with one another.

Barbiturates are medications used for treating headaches, insomnia, and seizures. Barbiturates are one of the older classes of medications.

Examples of barbiturates available in the U.S. include:

• amobarbital (Amytal)
• butabarbital (Butisol)
• pentobarbital (Nembutal)
• secobarbital (Seconal)
• belladonna and phenobarbital (Donnatal)
• butalbital/acetaminophen/caffeine (Esgic, Fioricet)
• butalbital/aspirin/caffeine (Fiorinal Ascomp, Fortabs)

Common side effects of barbiturates are:

• dizziness,
• drowsiness,
• headache,
• sedation,
• low blood pressure (hypotension)
• lightheadedness,
• sedation,
• headache,
• skin rash,
• nausea,
• vomiting, and
• abdominal pain.

Serious side effects of barbiturates include:

• abnormally slow breathing
• coma
• confusion
• fainting
• hallucinations
• temporary breathing cessation

Rare side effects of barbiturates include:

• agranulocytosis
• erythroderma
• liver injury
• megaloblastic anemia
• Stevens-Johnson syndrome

Barbiturates can slow breathing, reduce heart rate, and they can be habit forming.

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

Barbiturates should be used with caution with some medications because they accelerate the breakdown of these medications leading to decreased effectiveness. Examples of these medications that interact with barbiturates include:

• atazanavir (Reyataz),
• boceprevir (Victrelis),
• lurasidone (Latuda),
• ranolazine (Ranexa),
• telaprevir (Incivek),
• voriconazole, (Vfend), 
• ritonavir (Norvir),
• alcohol
• anticoagulants
• antihistamines
• birth control pills
• corticosteroids
• estrogen
• monoamine oxidase inhibitors (MAOIs)
• progesterone

Concomitant use of barbiturates and other central nervous system depressant medications should be used with caution because concomitant use can lead to excessive sedation, lethargy, and in severe cases coma and death. Examples of these medications that should be used with caution with other central nervous system depressant medications such as:

• alprazolam (Xanax),
• clonazepam (Klonopin),
• diazepam (Valium),
• zolpidem (Ambien), and
• zaleplon (Sonata).

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.

• Amobarbital and pentobarbital are available as injections.
• Butabarbital, phenobarbital, belladonna and phenobarbital, butalbital/aspirin/caffeine, and butalbital/acetaminophen/caffeine are available as tablets.
• Butalbital/acetaminophen/caffeine, butalbital/aspirin/caffeine, and secobarbital are available as capsules.
• Butabarbital, phenobarbital, belladonna and phenobarbital, and butalbital/acetaminophen/caffeine are available as oral liquids.

• FDA has listed amobarbital, phenobarbital, pentobarbital, secobarbital as Pregnancy Category D. This means they should not be used during pregnancy.
• FDA has listed belladonna and phenobarbital, butabarbital, butalbital/acetaminophen/caffeine, and butalbital/acetaminophen/caffeine as Pregnancy Category C. Pregnancy Category C classification means that there is no evidence of safe and effective use of barbiturates established for pregnant women. Therefore, risk to the infant cannot be ruled out. It is not known whether barbiturates enter breast milk; however, barbiturates should be avoided in nursing mothers to avoid harm to the infant.