Secobarbital

Secobarbital

Chemical structure of Secobarbital

Secobarbital, also known by the brand name Seconal, is a barbiturate derivative that has been used primarily as a sedative and hypnotic medication. It is known for its rapid onset and short duration of action, making it effective for inducing sleep in patients with insomnia.

Pharmacology

Secobarbital acts as a central nervous system depressant. It enhances the activity of the gamma-aminobutyric acid (GABA) neurotransmitter by binding to the GABA_A receptor, which increases the duration of the opening of the chloride ion channel, leading to hyperpolarization of the neuron and decreased neuronal activity.

Mechanism of Action

The primary mechanism of action of secobarbital involves potentiation of GABAergic transmission. By binding to the GABA_A receptor, secobarbital increases the inhibitory effects of GABA, resulting in sedation, hypnosis, and anxiolysis. This action is similar to that of other barbiturates, although secobarbital is noted for its relatively short half-life.

Medical Uses

Secobarbital is primarily used for the short-term treatment of insomnia, particularly in patients who have difficulty falling asleep. It is also used as a pre-anesthetic agent to reduce anxiety and induce sedation before surgical procedures.

Dosage and Administration

Secobarbital is typically administered orally in capsule form. The usual adult dose for insomnia is 100 mg taken at bedtime. For preoperative sedation, the dose may vary depending on the patient's age, weight, and medical condition.

Side Effects

Common side effects of secobarbital include drowsiness, dizziness, and headache. More serious side effects can include respiratory depression, hypotension, and allergic reactions. Long-term use can lead to tolerance, dependence, and withdrawal symptoms.

Overdose and Toxicity

Ball-and-stick model of Secobarbital

Overdose of secobarbital can result in severe respiratory depression, coma, and death. Treatment of overdose involves supportive care, including airway management and mechanical ventilation if necessary. Activated charcoal may be administered to reduce absorption if the overdose is recent.

Legal Status

Secobarbital is classified as a Schedule II controlled substance in the United States, indicating a high potential for abuse and dependence. Its use is strictly regulated, and prescriptions are limited to short-term use.

History

Secobarbital was first synthesized in the early 20th century and became widely used in the 1930s and 1940s. It was initially marketed under the brand name Seconal and became popular as a sleep aid. However, due to the risk of addiction and the development of safer alternatives, its use has declined over the years.

Related Pages

• Barbiturate
• Insomnia
• GABA_A receptor
• Sedative

Secobarbital capsules

See Also

• Phenobarbital
• Pentobarbital
• Benzodiazepine