What are Barbiturates used to treat?

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Barbiturates are a group of drugs derived from barbituric acid that act as depressants to the central nervous system. These drugs are often used for medical purposes as sedatives or anesthetics. Barbiturates are actually known as CNS depressants or central nervous system depressants. Barbiturates are derivatives of barbituric acid. Barbiturates have both physical and mental addiction. Currently, Barbiturates have been greatly substituted by benzodiazepines, a psychoactive drug used in general medical practices such as, for treating anxiety and insomnia. This is because benzodiazepines are extensively less dangerous in overdose. On the other hand, barbiturates are still used in general anesthesia, as well as for epilepsy. Barbiturates comprise a greater danger than alcohol or heroin. If it is used under medical supervision, barbiturates are remarkably safe and effective. They are widely used and widely distributed legally, but more widely abused and misused illegally. Owing to the number of fatal accidents from their misuse they are now largely replaced by tranquillizers.


What is the History of Barbiturates?

Barbituric acid was first produced on December 6, 1864, by German scientist Adolf Von Baeyer. This was done by condensing urea and diethyl malonate - an ester derived from the acid of apples. Barbituric acid on its own does not encourage any effect on the central nervous system, but there are over 2,500 barbiturate compounds that possess pharmacological properties. Medicinal properties of barbiturates were not discovered until 1903. In 1903, two German chemists Emil Fischer and Joseph von Mering working at Bayer, a pharmaceutical company discovered that barbital was very effective as a sedative when they conducted experiments on dog. In 1912, Bayer commenced phenol barbital, which was another barbituric acid derivative under the trade name Luminal, as a sedative mesmerizing.


What is Barbiturates made of?

Barbiturates are compounds derived from barbituric acid, a substance made from carbon, hydrogen, nitrogen, and oxygen.


How does Barbiturates work?

All Barbiturates slow down the activity of neurons in the brain by overstressing the actions of a naturally occurring neurotransmitter, called ‘gamma-amino butyric acid’. There are different varieties barbiturates which have several uses depending on how long they last in the body.


How are Barbiturates employed for medical uses?

Barbiturates can be injected into the veins or muscles, but they are usually taken in pill form. Doctors use short-acting barbiturates as general anesthetics. A single injection of barbiturates can sedate the patient in 10– 20 seconds. Consciousness returns in 20-30 minutes. Doctors use longer-lasting types, like Phenobarbital, to treat epilepsy. Barbiturates like pentobarbital and phenobarbital were earlier used as anxiolytics and hypnotics, but have now been replaced with benzodiazepines. An overdose of benzodiazepines has less potential for producing fatal effects. Pentothal and especially other short-acting barbiturates are mostly used in hospital settings as they are not likely to be abused. Phenobarbital is a useful anticonvulsant for people suffering from seizure disorders such as febrile seizures, tonic-clonic seizures, status epilepticus, and eclampsia. All barbiturates are very addictive and so cannot be used for an extended period to time.


What are some examples of Barbiturates?

Several examples of Barbiturates are:

  • Allobarbital
  •  Amobarbital
  •  Barbital
  •  Pentobarbital
  •  Phenobarbital
  •  Secobarbital
  •  Thiopental
  •  Cyclobarbital
  •  Methylphenobarbital
  •  Talbutal

Nowadays, benzodiazepines are usually used in place of barbiturates for medical purposes. Barbiturates are not the preferred choice due to their narrow margin of safety and highly addictive properties.


What are the behavioral effects of Barbiturates?

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

  • In low doses: In low doses, barbiturates decrease anxiety, decrease respiration, lessen blood pressure, decrease heart rate and decrease rapid eye movement (REM) sleep.
  •  In higher doses: In higher doses, barbiturates can in fact increase some types of behavior and act like a stimulant. These effects may be caused by depression of inhibitory brain circuits. Overall, barbiturates at these doses act to remove inhibitory behavior.


What are the effects of Barbiturates on brain?

Barbiturates have the capacity to melt readily in fat. So, barbiturates have complete access to the brain as they can cross the blood brain barrier very easily. Moreover, as barbiturates dissolve into body fat, they can build up and re-enter the blood stream later on. Various barbiturates clear out of the blood stream at various rates. While the accurate techniques by which barbiturates affect the brain are not obvious, it is assumed that these drugs bind to sodium channels on neurons and prevent the flow of sodium ions. Since, sodium ions cannot flow across the neuronal membrane, action potentials cannot be produced. Barbiturates may also increase the flow of chloride ions across the neuronal membrane. This may take place through binding to the receptor for the neurotransmitter called GABA. The increased chloride ion flow reduces the chance that an action potential will be produced.


What is the primary issue with Barbiturates?

A key issue with barbiturates is that they may lead to tolerance and dependence.

  • Tolerance happens when a larger quantity of the drug is needed to get the preferred effect. For instance, if barbiturates are used to help a person sleep, eventually, a greater dose of the drug will be required to get the person to sleep.
  •  Dependence happens when a patient feels like he/she should use the drug and withdrawal symptoms occur when the person stops using the drug.


What are the Withdrawal symptoms of barbiturates?

Withdrawal symptoms that take place when people try to get rid of using barbiturates include:

  •  nervousness
  •  sleeplessness
  •  seizures
  •  nausea, stomach troubles
  •  hallucinations

With the increasing number and severity of withdrawal symptoms associated with these drugs, it is best that a patient detox or recover in a drug treatment program.


What are the serious complications of barbiturates?

Regrettably, abuse of this substance could lead to respiratory arrest, one of the major causes of death in barbiturate abusers. Overdose symptoms include some serious complications such as:

  • Confusion
  •  Slurred speech,
  •  Drowsiness, and fatigue
  •  Nausea and vomiting
  •  Impaired motor coordination
  •  Sedation and somnolence
  •  Memory impairment
  •  Wrong thinking
  •  Highly hazardous interactions with other drugs.
  •  Deficit of safety and selectivity.
  •  A propensity to create reliance, tolerance, mistreatment and withdrawal.
  •  Heavy users are also at risk of pneumonia and bronchitis may even result in coma or death.


How are barbiturates taken?

Barbiturates can be taken in the form of capsules and tablets. However, barbiturate salts can be mixed with water and injected. They are also taken rectally, while this is rarely done.

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