AMISULPRIDE HAS FAR LESS SIDE-EFFECTSOne distinguishable trait of amisulpride is that lower doses seem to only, or mostly block the dopamine D2S (autoreceptors) (2) - which leads to an actual enhancement in dopamine release(3). Most of the usual antipsychotics we hear about, e.g risperidone, thorazine and haldol - all have very potent dual action dopamine receptor blockade(4). This leads to many more side-effects, including incidences of depression and high rates of drug-induced tardive dyskinesia(5).
Additionally, most anti-psychotic drugs have extremely potent alpha-1-adrenergic receptor blockade(6) (7), amisulpride lacks this property, as well as the usual anti histamine property of anti-psychotics (8) - which means AmiSulpride is very unlikely to cause any form of sedation(9).
Usually, the anti-histamine properties of other anti-psychotic drugs combined with the alpha-1-blockade - acts as a one-two punch in knocking the patient out cold....frequently we hear about some of the affected even drooling on themselves or just completely incoherent and lethargic the following day(10)!
While some medical professionals consider this a benefit in hostile or unpredictable patients, I would find it much less than ideal for someone who wants to maintain somewhat of a normal life , not incapacitated but with symptoms controlled(11).
Besides lack of side-effects, or at least lack of sedation - amisulpride has one very notable effect that sets it apart from other drugs in its class - it's anti-depressant effects are VERY FAST ACTING, very potent - and generally yield little to no negative endocrine effects(12).
The mechanism of action is totally unique, amisulpride binds to the serotonin 5-HT(7) with 11.5 nanomolar (ki/nm) affinity - this includes in human subjects(14).
It antagonizes the action of serotonin at this receptor - resulting in an anti-depressant effect that can not only augment other anti-depressants - but can be much more effective alone than many anti-depressants(15).
The additional benefits of 5-HT(7) antagonism are that it will reduce overstimulation and anxiety - as well as treat depression - and lower cortisol levels as well(16).
Because many depressed patients exhibit HPAA (hypothalamic-pituitary-adrenal-axis) dysfunction - and often have elevated cortisol - this unique mechanism of action may benefit the hormonal balance of depressed patients..(17) unlike SSRI's which tend to increase stress hormones (18) and oppose other beneficial neurotransmitters such as GABA, dopamine and others(19)!
Thus, in summary...
Amisulpride has the following benefits / advantages over other drugs aiming to do the same.
- A cortisol reduction, instead of increase.
- Enhances dopamine at lower doses.
- Little to no sedation, drowsiness, dyskinesia, tremors , punding or other disturbing side-effects.
- Doesn't interfere with cognitive function or vigilance.
- Treats depression quickly , and effectively.
- May improve anxiety symptoms as well.