Insomnia and its treatment
Criteria for defining insomnia includes an average sleep latency of > 30 minutes, wakefulness after sleep onset > 30 minutes,. Sleep efficiency of < 85% and total sleep time < 6.5 hours.
Agents that treat insomnia:
- Reduce brain activation, enhancing sleep drive, activation of GABA IN HYPOTHALAMIC SLEEP CENTER (VLPO) -VENTRAL LATERAL Preoptic Area
- Positive allosteric modulators of GABAa -benzodiazepines and Z. Drugs.
- Reduce arousal by blocking orexins (DORAS) blocking H1, Blocking serotonin (HT2 A antagonists) and blocking norepinephrine (alpha 1 antagonists)
Benzodiazepine facilitate GABA neurotransmission in inhibitory sleep circuits arising from the hypothalamic VLPO.
Benzodiazepines and Z drugs target GABAA receptors that have a gamma subunit. Postsynaptic, and mediate physic inhibitory neurotransmission. This also can lead to tolerance and dependence.
DORAs
Block the wake stabilizing effects of the orexins especially at orexins 2 receipts. Act on both orexins 1 and 2.
They prevent the release of wake promoting neurotransmitters.
Bought to lack dependence and withdrawal.
Suvorexand and Lemborexant, drug names.
Lemborexant may wear off sooner in am.
Trazodone
5HT2A/alpha 1/H1 antagonist
Antidepressant. Works to reduce arousal
5HT2A specifically enhances slow-wave sleep/deep sleep.
Antihistamine as mechanism of action:
Doxepin at low doses almost pure H1 blocker
Benadryl
alpha 2 delta ligands: open channel, N and P/Q voltage-gated ion-channel inhibitors. Can enhance slow wave sleep, restorative sleep, and help with pain management.
Gabapentin
Pregabalin (Lyrica)
Behavioral treatments
Relaxation training, meditation, stimulus control therapy, CBT, and other forms of psychotherapy.