Author: Gary Jackson

Barbiturates: Usage, Effects, and Signs of Barbiturate Overdose

All barbiturates affect gamma-aminobutyric acid (GABA), a
neurotransmitter (chemical) that nerves use to communicate with one another. A key reason why healthcare providers don’t prescribe barbiturates as often now is the risk of misusing them. Because of that risk, you should keep these medications under lock and key in a secure place in your home.

Barbiturates belong to the group of medicines called central nervous system (CNS) depressants (medicines that cause drowsiness). They act on the brain and CNS to produce effects that may be helpful or harmful. This depends on the individual patient’s condition and response and the amount of medicine taken. The World Health Organization (WHO) list it as a first-line treatment for epilepsy for adults and children in the developing world, because of its low cost and proven effectiveness.

Subscribe to MedicineNet’s General Health Newsletter

Barbital was first synthesized in 1903, and phenobarbital became available in 1912. Barbiturates act by depressing the central nervous system, particularly on certain portions of the brain, though they tend to depress the functioning of all the body’s tissues. Most of them exert a sedative effect in small doses and a hypnotic effect in larger doses. The barbiturates have largely been replaced as sedatives by the benzodiazepines and other minor tranquilizers, which have fewer unfavourable side effects and less abuse potential. Barbiturates, such as phenobarbital, were long used as anxiolytics and hypnotics. Intermediate-acting barbiturates reduce time to fall asleep, increase total sleep time, and reduce REM sleep time.

However, while GABAA receptor currents are increased by barbiturates (and other general anesthetics), ligand-gated ion channels that are predominantly permeable for cationic ions are blocked by these compounds. Those who died of a combination of barbiturates and other drugs include Rainer Werner Fassbinder, Dorothy Kilgallen, Malcolm Lowry, Edie Sedgwick and Kenneth Williams. Dorothy Dandridge died of either an overdose or an unrelated embolism. Ingeborg Bachmann may have died of the consequences of barbiturate withdrawal (she was hospitalized with burns, the doctors treating her not being aware of her barbiturate addiction). There are special risks to consider for older adults, and women who are pregnant. When a person ages, the body becomes less able to rid itself of barbiturates.

Do Seizures Come in Clusters?

Barbituric acid itself does not have any direct effect on the central nervous system and chemists have derived over 2,500 compounds from it that possess pharmacologically active qualities. The broad class of barbiturates is further broken down and classified according to speed of onset and duration of action. Ultrashort-acting barbiturates are commonly used for anesthesia because their extremely short duration of action allows for greater control. These properties allow doctors to rapidly put a patient “under” in emergency surgery situations.

People who use substances tend to prefer short-acting and intermediate-acting barbiturates.[43] The most commonly used are amobarbital (Amytal), pentobarbital (Nembutal), and secobarbital (Seconal). A combination of amobarbital and secobarbital (called Tuinal) is also highly used. Short-acting and intermediate-acting barbiturates are usually prescribed as sedatives and sleeping pills. These pills begin acting fifteen to forty minutes after they are swallowed, and their effects last from five to six hours. Further, barbiturates are relatively non-selective compounds that bind to an entire superfamily of ligand-gated ion channels, of which the GABAA receptor channel is only one of several representatives. This Cys-loop receptor superfamily of ion channels includes the neuronal nACh receptor channel, the 5-HT3 receptor channel, and the glycine receptor channel.

Key Facts About Barbiturates

Barbiturates are classified according to their duration of action. Barbiturates of intermediate duration of action, such as amobarbital and butabarbital sodium, act for 6 to 12 hours and are used to relieve insomnia. Short-acting barbiturates, such as pentobarbital and secobarbital, are used to overcome difficulty in falling asleep. With regular use, tolerance to the effects of barbiturates develops.

• While it doesn’t compel people to tell the truth, amobarbital can slow the central nervous system, making concentration more difficult.
• Barbiturates have been around since the 1860s, and they still see a use for many conditions today.
• Phenobarbital, for example, is common for treating seizures that resist first-line anti-seizure medications.
• They can also serve as backup when the first-line medications don’t work.
• This class of barbiturates is used almost exclusively as anticonvulsants, although on rare occasions they are prescribed for daytime sedation.
• However, most barbiturate use has been replaced by the development of newer, safer, alternative drugs.

If barbiturates are prepared as injection drugs, they are then classified as class A drugs, with the penalties for possession and supply being even more severe. Today, barbiturates are generally only used to treat extreme and serious cases of insomnia. They are also used to help control seizures in epilepsy, as well as an adjunct to anesthesia in some cases. 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.