The “ Z ” Compounds or Non-benzodiazepines

The non benzodiazepines also known as Z compounds.

1. Non – BZD Hypnotics ( The “ Z ” Compounds )

2. “ Z ” Compounds ) Newer compounds Chemically different from BZD’s Act specifically on BZD with α 1 subunit only Have selective hypnotic action and minimal other actions Shorter duration of action Lesser disturbance of sleep architecture Abuse potential is much lesser than even BZD’s

3. Zopiclone First Z compound Does not alter REM sleep, minimal disturbance of sleep architecture Slight prolongation of stages 3 & 4 Half life is 5-6 hrs Some degree of next morning impairment Tab 7.5 mg HS (not more than 2-4 weeks) Eszopiclone : Enantiomer of zopiclone Tolerance and dependence no/minimal Suitable for short/long term insomnia

4. Zolpidem Currently one of the most commonly prescribed hypnotic drug Pronounced hypnotic effect Half life is 2 hrs Fast action; sleep latency is shortened Next day sedation is minimal Minimal disturbance of sleep architecture No tolerance even on repeated use Tab 5-10 mg HS

5. Zaleplon Shortest acting Most selective for BZD receptors with α 1 subunit Half life is less than 01 hr No active metabolite Immediate action Only used for sleep onset Does not prolong sleep ; no morning sedation Can be given even late at night (4hrs before wakeup time) No tolerance even on repeated use Tab 5-10 mg HS

6. Ramelteon New class of hypnotic drugs MT1 & MT2 receptor agonist Indications: - Sleep onset insomnia - Speeds sleep onset - Longer duration of sleep Advantages: - No dependence - No rebound insomnia Dose- 8 mg ½ hour before going to sleep

7. Tasimelteon MT 1 & MT 2 receptor agonist Recently approved by USFDA in Jan – 2014 Indications: Non 24-hour sleep wake disorder(N24SWD) in totally blind ADR - Headache, Nightmares. 7

8. Quazepam Oral Insomnia Active metabolites accumulate with chronic use 39 7.5-15 Temazepam Oral Insomnia Metabolized mainly by conjugation 11 ± 6 7.5-30 Triazolam Oral Insomnia Most rapidly inactivated benzodiazepine used for insomnia; may cause disturbing daytime side effects 2.9 ± 1.0 0.125-0.25

9. Zopiclone Eszopiclone Zolpidem Zaleplon T 1/2 5 – 6 hr 2 hr 1 hr Use Short term insomnia < 2 weeks Short term & chronic insomnia Short term use in Sleep onset insomnia, Intermittent awakenings Sleep onset insomnia Advantage -- -- No effect on sleep stages, Less day time sedation, No rebound insomnia, No tolerance, No abuse, Safety in overdose Late night, No day time anxiety, No rebound insomnia Dose 7.5 mg HS 5 – 10 mg HS 5 – 10 mg HS