Haldol mecanisme d action

Haloperidol is a typical butyrophenone type antipsychotic that exhibits high affinity dopamine D 2 receptor antagonism and slow receptor dissociation kinetics. [42] It has effects similar to the phenothiazines . [17] The drug binds preferentially to D 2 and α 1 receptors at low dose (ED 50 = and  mg/kg, respectively), and 5-HT 2 receptors at a higher dose (ED 50 =  mg/kg). Given that antagonism of D 2 receptors is more beneficial on the positive symptoms of schizophrenia and antagonism of 5-HT 2 receptors on the negative symptoms, this characteristic underlies haloperidol's greater effect on delusions, hallucinations and other manifestations of psychosis. [43] Haloperidol's negligible affinity for histamine H 1 receptors and muscarinic M 1 acetylcholine receptors yields an antipsychotic with a lower incidence of sedation, weight gain, and orthostatic hypotension though having higher rates of treatment emergent extrapyramidal symptoms .

Given these considerations, antipsychotic drugs should be prescribed in a manner that is most likely to minimize the occurrence of tardive dyskinesia. Chronic antipsychotic treatment should generally be reserved for patients who suffer from a chronic illness that 1) is known to respond to antipsychotic drugs, and 2) for whom alternative, equally effective, but potentially less harmful treatments are not available or appropriate. In patients who do require chronic treatment, the smallest dose and the shortest duration of treatment producing a satisfactory clinical response should be sought. The need for continued treatment should be reassessed periodically.

One injectable preparation is the long-acting decanoate ester which is used to treat schizophrenia and related conditions in patients who have had difficulty adhering to other medication plans. This can happen if patients have a poor understanding of their illness or because they forget to take their tablets. Patients are administered an injection once every four weeks. Haloperidol decanoate must only be administered intramuscularly and is not for intravenous use. The drug is quickly absorbed and has a high bioavailability. In healthy individuals, the Tmax is around 20 minutes, while it is minutes in people with schizophrenia. The T1/2 is just under 21 hours. The blood plasma haloperidol level reaches peak concentration at around six days post-administration and the half-life is approximately six weeks.

Haldol mecanisme d action

haldol mecanisme d action


haldol mecanisme d actionhaldol mecanisme d actionhaldol mecanisme d action