In general, the high-milligram, low-potency antipsychotics, such as chlorpromazine and mesoridazine, produce more sedation than the low-milligram, high-potency antipsychotics such as haloperidol and fluphenazine (Table 1). This principle tends to hold true for the
Compared with low-potency first generation antipsychotics, only clozapine was significantly more sedating.
Olanzapine. Although olanzapine is more sedating than quetiapine, there are fewer reports of olanzapine for pharmacologic management of primary or secondary insomnia.
It seems that clozapine produces a lower increase of prolactin levels than olanzapine. On the other hand, clozapine is associated with a higher frequency of leukopenia (reduced white blood cell count), hypersalivation, sedation and seizures.
Compared with low-potency first-generation antipsychotics, only clozapine may be more sedating.
Among agents indicated for schizophrenia treatment, lurasidone and cariprazine were found to be predominately activating, while olanzapine, quetiapine (both immediate and extended-release), ziprasidone, asenapine, and iloperidone were predominately sedating.
One of the main ways that Seroquel helps people fall asleep is through its potent antihistamine properties. Histamine is a chemical in the body that promotes wakefulness, and by blocking the effects of histamine, Seroquel can help to reduce wakefulness and promote sleep.
Predominantly sedating are olanzapine, quetiapine immediate and extended release, ziprasidone, asenapine, and iloperidone. Agents that are neither activating nor sedating are paliperidone and brexpiprazole.
Olanzapine has better efficacy compared to risperidone for treatment of negative symptoms in schizophrenia.
Seroquel is an antipsychotic that helps to calm and relieve psychotic thoughts. It is often given because it is quite sedating; however, care is needed because it also lowers blood pressure.
At low doses (50 mg per day), quetiapine has well-demonstrated hypnotic and sedative effects attributable to histamine 1-receptor blockade. With midrange doses (300 mg per day), mood effects are secondary to both dopaminergic (D2 receptor) and serotonergic (5HT2A receptor) blockade.
Quetiapine may be slightly less effective than risperidone and olanzapine in reducing symptoms, and it may cause less weight gain and fewer side effects and associated problems (such as heart problems and diabetes) than olanzapine and paliperidone, but more than are seen with risperidone and ziprasidone.
Benzodiazepines are the most common group of prescribed sedatives. The most commonly prescribed benzodiazepines are diazepam (Valium®) and alprazolam (Xanax®).
Midazolam is the fastest acting of its class because of its lipophilic abilities, and it is superior to lorazepam and diazepam in its amnestic effects, making it the ideal benzodiazepine for use in short ED procedures.
High-potency benzodiazepines:
For its high-potency and long-lasting effects, the most potent benzodiazepine is Clonazepam, also known as Klonopin. Other high-potency but short-acting benzos are alprazolam (Xanax), lorazepam (Ativan), and triazolam (Halcion).
A study by Richelson and Souder7 of the binding profiles of antipsychotic medications found that olanzapine has the highest affinity for the histamine H1 receptors, followed by clozapine (Figure 1). This may explain why olanzapine has a relatively large sedative effect even though it is a high-potency medication.
Olanzapine can make you feel sleepy. If this happens to you, do not drive, ride a bike or use tools or machinery until you feel better. Some people find it hard to concentrate while they are taking olanzapine.
Insomnia: Olanzapine has been shown to improve sleep efficiency and sleep quality when combined with an SSRI in depressed patients starting with as little as 2.5 mg (21).
That being said, I would ask your doctor how long it should take for you to get drowsy. The patients I have who take this medication say that they are asleep within about 30 minutes, but they are often on other medications such as pain meds, etc.
Antidepressants: Certain antidepressants can be effective in treating anxiety and racing thoughts. Selective serotonin reuptake inhibitors (SSRIs) are commonly used. Antihistamines: Some over-the-counter antihistamines, such as diphenhydramine (Benadryl®), can have a sedating effect and may be used to help with sleep.
Quetiapine works by attaching to the brain's dopamine receptors and altering serotonin levels. Short-term effects include feeling sleepy, a dry mouth, dizziness and low blood pressure when you stand up. These effects lasts about six hours.
Clozapine, which has the strongest antipsychotic effect, can cause neutropenia.
Drugs with the fastest onsets include haloperidol, risperidone, and olanzapine, with onsets appearing in 2 6 days. Chlorpromazine and thiothixene were at the slowest end of the continuum, with onsets of 2 weeks or longer.
Second-generation antipsychotics (SGAs) have a decreased risk of extrapyramidal side effects as compared to first-generation antipsychotics. SGAs are associated with significant weight gain and the development of metabolic syndrome.