Do you often find yourself popping sleeping pills, to get hold of that elusive thing: sleep. Then this article is a must read for you.
Sleeping pills are pills that can induce sleep. These constitute substances that trigger or suppress certain brain activities which result in causing sleep.
Sleeping pills are based on medical research on brain and sleep and over a span of several decades sleeping pills with the differential mode of action as well as improved mode of action have been introduced.
One or more categories of sleep inducers can have a similar mode of action whereas sleep inducers of other different categories may induce sleep through different molecular pathways. Medical practitioners prescribe the suitable sleeping pill after thoroughly diagnosing the patient and problem.
The habit of buying sleeping pills over the counter and popping them without regard has been largely criticized by the medical fraternity as several times such practices lead to substance abuse, side effects and addiction.
1Sleep inducing mechanism
The following categories of sleep-inducing substances are based on differential mechanisms
- Barbiturates, Benzodiazepines, Non-benzodiazepines (‘Z-drugs’): This sleep inducer category is based on increasing effect of GABA (γ-aminobutyric acid) by binding to the GABA receptor. In the hypothalamus, the ventrolateral preoptic nucleus (VLPO) uses GABA to induce sleep, if GABA increases sleep is induced. Drug category includes phenobarbital, chlordiazepoxide, diazepam, temazepam, zolpidem, zopiclone, eszopiclone.
- Antihistamines: This category of sleeping drug is actually a sleep When histamine increases in the ascending arousal system, the sleeping person wakes up, so this category of drug blocks histamine thus preventing arousal. Examples include diphenhydramine and hydroxyzine.
- Antidepressants: This category of sleep medicine is usually prescribed to people with depression and when sleeplessness is being caused by depression. These sleep substances act by inhibiting serotonin and histamine receptors. Examples include trazodone and nefazodone.
- Adrenergic agonists: The sleep inducing mechanisms of adrenergic agonists include blocking of neurons that release noradrenaline, blocking of ascending arousal system and activation of ventolateral preoptic nucleus (VLPO). An example includes dexmedetomidine.
- Malatonin agonists: VLPO is activated through circadian cue by the melatonin receptors. Melatonin agonists activate these melatonin receptors, thus inducing sleep. Examples include melatonin, ramelteon.
- Orexin receptor antagonists: Orexin neurons are responsible for signals that cause the body to wake up. The orexin receptor antagonists block these neurons and the waking up signals are inhibited thus prolonging sleep. Examples include Suvorexant, SB-649,868. (these drugs have not been approved yet).