The high-potency, first-generation antipsychotics, such as fluphenazine, trifluoperazine, haloperidol, loxapine, pimozide, perphenazine, and thiothixene, are dosed in the range of one to tens of milligrams.
high-potency antipsychotic
any of various conventional antipsychotics that have either a relatively high degree of affinity for the dopamine D2 receptor or significant extrapyramidal symptoms. High-potency antipsychotics include fluphenazine, haloperidol, thiothixene (see thioxanthene), trifluoperazine, and pimozide.
High- and low-potency antipsychotics also seem to differ in their side-effects. Low-potency drugs cause sedation and poor muscle strength, whereas high-potency drugs produce side-effects such as movement disorders (the inability to sit still, uncontrollable shaking and difficulty in walking).
High potency antipsychotics have a higher risk for extrapyramidal symptoms (EPS) and hyperprolactinemia. Low potency antipsychotics have more anticholingeric symptoms and are more sedating. Typical antipsychotics have a higher propensity to cause EPS, where as atypicals are more likely to cause metabolic syndrome.
Fluphenazine is a high-potency typical antipsychotic that blocks postsynaptic dopaminergic D1 and D2 receptors. It has some alpha-adrenergic and anticholinergic effects. It is available orally and in a depot formulation (fluphenazine decanoate).
Chlorpromazine is a low potency antipsychotic which is used with psychosis, schizophrenia and manic episodes. This drug has the side effect of hypotension and also has anti-histamine properties, which counteract the extrapyramidal symptoms experienced with antipsychotics.
Typical antipsychotics tend to more strongly block dopamine. Atypical antipsychotics have greater effects on serotonin. Both groups of antipsychotics share similar side effects, such as dry mouth, sleepiness, and weight gain. But typical antipsychotics have a higher risk of uncontrollable body movements.
[Olanzapine--high potency antipsychotic drug inducing significant weight gain: a case report]
For example, the high-potency, low-dose atypical antipsychotic risperidone is less sedating than the lower-potency, high-dose atypical antipsychotics quetiapine and clozapine. However, dose does not always determine sedation.
In addition to its potency at 5HT2A receptors, clozapine is very potent at the muscarinic M1 receptor with a dissociation constant of Ki = 9.5 nM.
A highly potent drug (e.g., fentanyl, alprazolam, risperidone, ) evokes a given response at low concentrations, while a drug of lower potency (meperidine, ziprasidone, furosemide) evokes the same response only at higher concentrations. Higher potency does not necessarily mean greater effectiveness or more side effects.
Aripiprazole is a low potency partial agonist at the 5-HT1A receptor stably expressed in 1ACHO cells. Inhibition of forskolin-stimulated cAMP production was compared for serotonin and aripiprazole.
The main difference between the two types of antipsychotics is that the first generation drugs block dopamine and the second generation drugs block dopamine and also affect serotonin levels.
Clozapine is an atypical antipsychotic demonstrated to be superior in the treatment of refractory schizophrenia which causes fewer movement disorders.
LOCATION, LOCATION, LOCATION: “GOLD–STANDARD” SCHIZOPHRENIA TREATMENT VARIES BY STATE. Dramatic differences exist in how widely clozapine – widely regarded as the “gold standard” of schizophrenia treatment – is prescribed from state to state, according to a new report published by the Treatment Advocacy Center.
Antipsychotic medications are the first-line medication treatment for schizophrenia. They have been shown in clinical trials to be effective in treating symptoms and behaviors associated with the disorder. However, antipsychotic medications have significant side effects.
Potency is perhaps most commonly used in a medical context, in which it refers to the strength of the effect that something can have on the body. A substance with high potency will have a big effect on the body, and something with low potency will have a smaller one.
This means a supplement may be labeled as “high potency” for each nutrient(s) that is present at 100% of the RDI per serving.
Results: Potency is an expression of the activity of a drug in terms of the concentration or amount of the drug required to produce a defined effect, whereas clinical efficacy judges the therapeutic effectiveness of the drug in humans.
The comparison on GASS between the two groups revealed significant difference at each assessment, and clozapine was found to be superior than risperidone.