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Created Dec 2020



DEA CODE 2270: Schedule 2

Pentobarbital is a prescription drug and a short-acting barbiturate that is used in medical environments for pre-surgery sedation and for the emergency treatment of seizures. It is also prescribed by doctors for short-term relief of insomnia. In rare cases, Pentobarbital has also been used for executions, but this specific use of the drug is highly controversial. Pentobarbital works by slowing the activity in the brain and nervous system by increasing the levels of a neurotransmitter called gamma-aminobutyric acid (GABA), which provides a calming effect. It comes in tablet, capsule, liquid, and powder form. It is a highly addictive and dangerous drug, especially when it is taken with other depressants like alcohol or narcotics. Due to its addictive nature, pentobarbital is meant to be used on a short-term basis.

Slang names:

  • Barbs
  • Phennies
  • Yellow jackets

Pentobarbital acts as a brain and central nervous depressant:
This prescription medication is classified as a barbiturate, which is a type of drug that works as a sedative by slowing brain function and central nervous system processes.

Pentobarbital is prescribed by a doctor to sedate patients before surgery or as a medication to treat insomnia. This medication slows down brain processes, which allows your mind and body to relax as you go to sleep.

Pentobarbital is a medication that is injected - usually by a doctor - therefore sticking to a dosage schedule is usually not an issue. Pentobarbital is a depressant that impacts neurotransmitters within the brain. This medication leaves you feeling drowsy and dizzy, and it is typically used as a sedative before surgery or as a short-term treatment for insomnia. Pentobarbital is also injected as an emergency treatment if someone is experiencing a seizure. Pentobarbital should only be recommended as a short-term solution for surgery and insomnia issues, as it may become habit-forming if taken without a proper prescription.

Common side effects of Pentobarbital include dizziness, drowsiness, loss of coordination, nausea, vomiting, or constipation. You should avoid drinking alcohol while on Pentobarbital to prevent serious side effects or a possible blackout, due to the depressant qualities of both substances. Never take Pentobarbital in addition to any other sleep aids or muscle relaxers, as this can result in respiratory failure and death.

Pentobarbital is a short-acting barbiturate:
This means the effects of the drug are felt quite quickly, however, they do not last that long compared to long-acting drugs. As a barbiturate and central nervous system (CNS) depressant, this drug can produce drowsiness, sedation and a hypnotic state. For these reasons, it may be used prior to surgery, to reduce seizure activity or in more limited instances, as a sleeping pill for insomnia.

Pentobarbital is delivered two ways, either in an oral or parenteral (non-oral) form. The oral capsule is currently not available in the United States, however, the parenteral form may be mixed with flavored syrup and delivered by mouth.

Pentobarbital can quickly cause a tolerance. Because of this, its use as a medication for insomnia is not typically accepted or recommended for prolonged periods of time. If, however, it's used to treat problems sleeping, it's recommended that the medication is used no more than two weeks.

Pentobarbital is a potent prescription barbiturate drug with a high potential for abuse and addiction. For these reasons, even within prescribed use, this substance is highly monitored and recommended for only brief periods of treatment.

Pentobarbital is a short-acting oral and parenteral barbiturate. It has sedative-hypnotic and anticonvulsant properties, and is used primarily in the

  • Short-term treatment of insomnia.
Other uses include:
  • Sedation induction
  • Relief of preoperative anxiety
  • Control of status epilepticus or seizures resulting from Meningitis, Tetanus, Alcohol withdrawal, Poisons, Chorea, or eclampsia
  • Induction of coma in the management of cerebral ischemia and increased intracranial pressure that may follow stroke or head trauma
Pentobarbital was approved by the FDA in 1939.

Thoughts of Suicide:
NOTE: In January 2008, the FDA alerted healthcare professionals of an increased risk of suicidal ideation and behavior in patients receiving anticonvulsants to treat epilepsy, psychiatric disorders, or other conditions (e.g., migraine, neuropathic pain). In the analysis, patients receiving anticonvulsants had approximately twice the risk of suicidal behavior or ideation (0.43%) as patients receiving placebo (0.22%). The relative risk for suicidality was higher in patients with epilepsy compared to those with other conditions. Drug data were analyzed by the FDA for carbamazepine, felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, pregabalin, tiagabine, topiramate, valproate, and zonisamide; however, this is considered to be a class effect. All patients beginning treatment with anticonvulsants or currently receiving such treatment should be closely monitored for emerging or worsening suicidal thoughts/behavior or depression.

Pentobarbital belongs to the class of a short-acting barbiturate is used as sedatives, hypnotics, for the short-term treatment of insomnia, since they appear to lose their effectiveness for sleep induction and sleep maintenance after 2 weeks; preanesthetics and anticonvulsant, in anesthetic doses, in the emergency control of certain acute convulsive episodes, e.g., those associated with status epilepticus, cholera, eclampsia, meningitis, tetanus, and toxic reactions to strychnine or local anesthetics. Pentobarbital binds at a distinct binding site associated with a Cl-ionopore at the GABAA receptor, increasing the duration of time for which the Cl-ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged. All of these effects are associated with marked decreases in GABA-sensitive neuronal calcium conductance (gCa). The net result of barbiturate action is acute potentiation of inhibitory GABAergic tone. Barbiturates also act through potent (if less well characterized) and direct inhibition of excitatory AMPA-type glutamate receptors, resulting in a profound suppression of glutamatergic neurotransmission.

Important Information

You should not use pentobarbital if you have a history of porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system).

Pentobarbital can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Do not drink alcohol. Dangerous side effects can occur when alcohol is combined with pentobarbital.


Drug Interactions (484) Alcohol/Food Interactions (2) Disease Interactions (13)

What other drugs will affect Pentobarbital?
Using pentobarbital with other drugs that make you sleepy or slow your breathing can cause dangerous or life-threatening side effects. Ask your doctor before taking a sleeping pill, narcotic pain medicine, prescription cough medicine, a muscle relaxer, or medicine for anxiety, depression, or seizures. Tell your doctor about all other medications you use, especially:
  • doxycycline
  • griseofulvin
  • birth control pills or hormone replacement estrogens
  • a blood thinner:
    • warfarin
    • Coumadin
    • Jantoven
  • an MAO inhibitor:
    • isocarboxazid
    • linezolid
    • methylene blue injection
    • phenelzine
    • rasagiline
    • selegiline
    • tranylcypromine
    • and others
  • other seizure medications:
    • divalproex
    • phenytoin
    • valproic acid (Depakene)
  • steroid medicine:
    • prednisone
    • dexamethasone
    • prednisolone
    • and others
This list is not complete. Other drugs may interact with pentobarbital, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

A total of 484 drugs are known to interact with Pentobarbital.

  • 32 major drug interactions
  • 431 moderate drug interactions
  • 21 minor drug interactions

It is reported that Elvis was found with ten times the standard amount of codeine in his body. He was also reportedly addicted to a variety of substances, such as diazepam, methaqualone, phenobarbital, ethchlorvynol and ethinamate. The toxicology report concluded, at the time, that 'the strong possibility is that these drugs were the major contribution to his demise'. But modern medical advancements now suggest that his underlying heart problems were exacerbated by the heady concoction of drugs found in his system - but they were not a direct cause.

Marilyn Monroe:
Hollywood's brightest star, was found dead in the bedroom of her Brentwood, Los Angeles home. She was only 36. On Marilyn's bedside table was a virtual pharmacopoeia of sedatives, soporifics, tranquilizers, opiates, "speed pills," and sleeping pills. The vial containing the latter, a barbiturate known as Nembutal, was empty. In her last weeks to months, Marilyn was also consuming, if not abusing, a great deal of other barbiturates (amytal, sodium pentothal, seconal, phenobarbital), amphetamines (methamphetamine, Dexedrine, Benzedrine and dexamyl - a combination of barbiturates and amphetamines used for depression), opiates (morphine, codeine, Percodan), the sedative Librium, and alcohol (Champagne was a particular favorite, but she also imbibed a great deal of Sherry, vermouth and vodka).

Nembutal (pentobarbital)
Side Effects:
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
  • confusion, agitation, hallucinations
  • weak or shallow breathing
  • slow heart rate, weak pulse
  • a light-headed feeling, like you might pass out
Side effects such as confusion, depression, or excitement may be more likely in older adults and those who are ill or debilitated.
Common side effects may include:
  • drowsiness, dizziness
  • loss of balance or coordination
  • nausea, vomiting, constipation
  • overactive reflexes
  • sleep problems (insomnia), nightmares
  • feeling restless or excited (especially in children or older adults)
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Pentobarbital administration can be through three routes: intramuscular, intravenous, or oral.
  • For intramuscular administration, it is advised to inject no more than 5 ml and only into a large muscle to avoid tissue irritation or necrosis.
  • Intravenous administration is not to exceed 50 mg/minute and should only be given by slow IV injection in the undiluted form. It is essential to avoid tissue extravasation in this process as it has been known to cause tissue necrosis. Clinicians should avoid rapid IV injection as it can result in respiratory depression, hypotension, and bronchospasm, among other adverse effects.
  • In pediatric populations, oral administration is easier by mixing the drug with flavored syrup to improve the taste.

Nembutal (pentobarbital sodium)
Maximum Dosage:
Prescribers Digital Reference
Adults:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations.
Geriatric:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations.
Adolescents:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations. For procedural sedation, doses above 6 mg/kg/dose IM/IV/PO (Max: 100 mg/dose) are not usually necessary.
Children:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations. For procedural sedation, doses above 6 mg/kg/dose IM/IV/PO (Max: 100 mg/dose) are not usually necessary.
Infants:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations. For procedural sedation, doses above 6 mg/kg/dose IM or IV and 8 mg/kg/dose PO (Max: 100 mg/dose) are not usually necessary.
Neonates:Specific maximum dosage information not available; individualize dosage based on clinical parameters and serum pentobarbital concentrations. For procedural sedation, doses above 6 mg/kg/dose IV are not usually necessary.


A CNS depressant drug that is of the barbituate class. Typically not used often as it is easier to OD on than benzodiazepines, the new alternative to barbituates. Used often for insomnia, to cause sedation.

RouteOnsetDurationAfter Effects
Tripsit Factsheets
Oral:15-60 minutes3-4 hours1-36 hours
IM:10-25 minutes3-4 hours1-36 hours
IV:1 minutes15-20 hours1-36 hours
Pentobarbital Duration
All other CNS depressants, also avoid if you have respiratory issues or liver issues as barbiturates are harsh on the liver.


  • Absorption:
    Absorbed rapidly after oral or rectal administration. Serum levels needed for sedation and hypnosis are 1 to 5 mcg/ml and 5 to 15 mcg/ml, respectively.
  • Distribution:
    Distributed widely throughout body. About 35% to 45% protein-bound. Accumulates in fat with long-term use.
  • Metabolism:
    Metabolized in liver.
  • Excretion:
    99% eliminated as glucuronide conjugates and other metabolites in urine. Terminal half-life ranges from 35 to 50 hours; duration of action 3 to 4 hours.

Overdose and treatment:
Toxicity may cause unsteady gait, slurred speech, sustained nystagmus, somnolence, confusion, respiratory depression, pulmonary edema, areflexia, and coma. Typical shock syndrome with tachycardia and hypotension may occur. Jaundice, hypothermia, then fever and oliguria also may occur. Serum levels greater than 10 mcg/ml may produce profound coma; levels greater than 30 mcg/ml may be fatal. To treat, maintain and support ventilation and pulmonary function as needed; support cardiac function and circulation with vasopressors and I.V. fluids, as needed. If patient is conscious and gag reflex is intact, induce emesis (if ingestion was recent) by administering ipecac syrup. If emesis is contraindicated, perform gastric lavage while a cuffed endotracheal tube is in place to prevent aspiration. Follow with administration of activated charcoal or sodium chloride cathartic. Measure intake or output, vital sighs, and laboratory parameters. Maintain body temperature. Alkalinization of urine may be helpful in removing drug from body. Hemodialysis may be useful in severe overdose.

Overdose Symptoms May Include:

  • Confusion, agitation
  • Decreased energy, sleepiness
  • Breathing that is difficult, slowed, or even stopped
  • Headache
  • Rash, large blisters
  • Slurred speech
  • Unsteady gait
  • Coma


Summary of Use During Lactation:
Because there is little published experience with pentobarbital during breastfeeding, other agents may be preferred, especially while nursing a newborn or preterm infant.

Alternate Drugs to Consider:

Pentobarbital is a sedative that slows the activity of the brain and nervous system. The drug is commonly used to euthanize pets.

"Since 2010, 14 states have used pentobarbital in over 200 executions and federal courts, including the Supreme Court, have repeatedly upheld the use of pentobarbital in executions as consistent with the Eighth Amendment," the Department of Justice said in a statement announcing the resumption of federal executions.

As opposed to prior executions, which used multiple drugs for lethal injection, federal executions will only use one drug: pentobarbital. Some states have already used the chemical for executions including Texas, Missouri and Georgia.

"Congress has expressly authorized the death penalty through legislation adopted by the people's representatives in both houses of Congress and signed by the President," Attorney General Barr said in a statement. "The Justice Department upholds the rule of law - and we owe it to the victims and their families to carry forward the sentence imposed by our justice system."

States started using it for executions in 2011, due to a shortage of sodium thiopental, which was previously used in executions - along with pancuronium bromide and potassium chloride.


"All barbiturates put the brain to sleep by slowing down brain function," said Dr. Mark A. Warner, president of the American Society of Anesthesiologists. "The brain cells that drive the desire to breathe are also suppressed. So any barbiturate, if you give enough of it, somebody quits breathing. Also, if you give enough of it the heart quits pumping as hard and that can cause decreased blood pressure."

Sodium thiopental is used in hospitals because it "has a relatively fast onset and it doesn't last long," Dr. Warner said. "You want a patient to go sleep and wake up pretty quickly."

Pentobarbital is a long-acting drug.

"If veterinarians are using this, they don't really care if an animal wakes up faster or not," Dr. Dombrowski said. "If the dog or cat is still a little sleepy it doesn't make a difference."

In euthanizing animals, higher doses are used, and "the lethal effect is a cardiovascular effect," Dr. Segal said, meaning that it stops the heart.

Pentobarbitol is used in hospitals in certain circumstances, like inducing a coma in brain-damaged patients because "that allows the brain to use more energy and oxygen to repair itself," Dr. Warner said. He said it can also be used to stop seizures in patients for whom other drugs are ineffective. Opponents of the death penalty object to either drug. Some say thiopental can wear off too quickly, allowing inmates to feel pain. Others object to using pentobarbital, because it is so infrequently used in humans.

Pentobarbital, a barbiturate that slows activity of the brain and nervous system, is often used by doctors to treat seizures and convulsions. In an execution, pentobarbital can be used in combination with other drugs or by itself. So far this year, 14 inmates have been executed by single-drug doses of pentobarbital - seven in Texas, six in Missouri and one in Georgia.

Suicide Tourism:
Mexico: A drug known as liquid pentobarbital is used by owners to euthanize pets. When given to humans, the drug can give them a painless death in under one hour. The pet shops across Mexico have such drugs. As a result, tourists from across the globe seeking to terminate their own lives were reported to be flying out to Mexico.

Animal Euthanasia:
Barbiturates rapidly became the leading non-inhalant drug used in animal euthanasia, as mentioned in the 1963 version of the AVMA Euthanasia Guidelines. Deemed the gentlest of the 'poisons', barbiturate overdoses lead to rapid unconsciousness, cessation of breathing, and cardiac arrest. Unconsciousness first was a guarantee before cardiac arrest so veterinarians could be certain awareness of death was nonexistent for the dying animal. This class of drug met all of the 14 criteria of method selection, save for a few, and even then, proper storage of barbiturates and disposal of the body was all it took to keep them top of the pack. Pure barbiturates held human abuse potential, and in 1972, were raised up from a Category III to a Category II controlled drug in the US. In an effort to reduce this abuse potential, synergistic drugs were added in to pure pentobarbital to increase safety and reduce some brands back down to Category IIIs. The best example of this is phenytoin sodium, a cardio-toxic substance.

Pentobarbital was originally only available in powder form. Veterinary services had to mix it precisely with the right type of water, alcohol, or other diluents and often found it unstable or with the wrong pH. In the early 1980's, North American Pharmacal, now Vortech Pharmaceuticals, found the right packaging and preservative formula that allowed room temp water to be added to the powder for easy storage and administration. Eventually, pentobarbital could be purchased in liquid form making handling even easier. Other forms of barbiturates exist today that are considered short acting, long acting, better for some symptoms compared to others, and so on. In brief, pentobarbital remains the most advanced drug for animal euthanasia, and will until something better comes along.

FP-3 and WANS info (Animal Euthanasia):
FP-3 is DEA Number 2271 Schedule 3: Pentobarbital & noncontrolled active ingredient
WANS is also DEA Number 2271 Schedule 3: Pentobarbital suppository dosage form

End FP-3 and WANS Animal Euthanasia info

caymanchem PDF Pentobarbital

A short-acting barbiturate typically used as a sedative, a preanesthetic, and to control convulsions in emergencies. It can also be used for short-term treatment of insomnia but has been largely replaced by the benzodiazepine family of drugs. In high doses, pentobarbital causes death by respiratory arrest. It is used for veterinary euthanasia and is used by some U.S. states for executions of convicted criminals. Pentobarbital was widely abused and known on the streets as "yellow jackets" due to the yellow capsule of the Nembutal brand. Pentobarbital in pill form is no longer available. The death of Marilyn Monroe in 1962 was ruled as probable suicide due to an overdose of pentobarbital.

Typical applications for pentobarbital are sedative, short term hypnotic, preanesthetic, insomnia, and control of convulsions in emergencies. Abbott Pharmaceutical discontinued manufacture of their Nembutal brand of Pentobarbital capsules in 1999, largely replaced by the benzodiazepine family of drugs.

Pentobarbital can cause death when used in high doses. It is used for euthanasia for humans as well as animals.

Pentobarbital has been used or considered as a substitute for other drugs traditionally used for capital punishment in the United States when they are in short supply. Texas began using pentobarbital for executing death-row inmates by lethal injection on July 18, 2012.

Prosecutors charge man with selling suicide drug after some buyers found dead - A federal grand jury indicted a Mexican man on drug charges for allegedly illegally importing the drug pentobarbital into the United States from Mexico for use in committing suicide – in some ...
Saturday June 01, 2024 -

Effects and Ethics of Execution Drugs - Yesterday, we reported on the Idaho Department of Correction's purchase of three more doses of Pentobarbital, a contraversial drug commonly used in executions.
Thursday May 30, 2024 -

Man from Mexico indicted in Chicago for allegedly importing suicide drug - A federal grand jury in Chicago has indicted a Mexican resident on charges of illegally importing and distributing the drug Pentobarbital from Mexico to the United States.Pentobarbital, commercially ...
Thursday May 30, 2024 -

Idaho buys another round of lethal injection drugs. Could next execution happen soon? - Idaho’s prison system appears to be advancing toward another lethal injection attempt following extensive national scrutiny three months ago, when prison officials called off the execution of an ...
Wednesday May 29, 2024 -

State of Missouri carries out execution of David Hosier Tuesday by lethal injection - David Hosier, a 69-year-old veteran convicted of killing a former lover, was executed by lethal injection. Gov. Mike Parson had denied clemency on Monday.
Tuesday June 11, 2024 -

Man accused in Chicago of shipping ‘suicide drug’ around the world - Gonzalez-Munguia is accused of the widespread sale of pentobarbital, a tightly controlled drug that has been used to carry out lethal injections. It is commercially available in Mexico for ...
Thursday May 30, 2024 -

Idaho buys more lethal injection drugs. Could next execution occur soon? - After IDOC stopped Creech’s execution on Feb. 28, the state bought the new round of pentobarbital. Idaho in the past six months paid $150,000 for 30 grams of lethal injection drugs — or what ...
Tuesday May 28, 2024 -

Prosecutors charge man with selling suicide drug after some buyers found dead - (The Center Square) – A federal grand jury indicted a Mexican man on drug charges for allegedly illegally importing the drug pentobarbital into the United States from Mexico for use in ...
Wednesday May 29, 2024 -

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