Pramipexole is a non-ergoline

Ergoline

Ergoline is a chemical compound whose structural skeleton is contained in a diverse range of alkaloids including a few psychedelic drugs . Ergoline derivatives are used clinically for the purpose of vasoconstriction and in the treatment of migraines and Parkinson's disease...

 dopamine agonist

Dopamine agonist

A dopamine agonist is a compound that activates dopamine receptors in the absence of dopamine. Dopamine agonists activate signaling pathways through the dopamine receptor and trimeric G-proteins, ultimately leading to changes in gene transcription.-Uses:...

 indicated for treating early-stage Parkinson's disease

Parkinson's disease

Parkinson's disease is a degenerative disorder of the central nervous system...

 (PD) and restless legs syndrome

Restless legs syndrome

Restless legs syndrome or Willis-Ekbom disease is a neurological disorder characterized by an irresistible urge to move one's body to stop uncomfortable or odd sensations. It most commonly affects the legs, but can affect the arms, torso, and even phantom limbs...

 (RLS). It is also sometimes used off-label

Off-label use

Off-label use is the practice of prescribing pharmaceuticals for an unapproved indication or in an unapproved age group, unapproved dose or unapproved form of administration...

 as a treatment for cluster headache

Cluster headache

Cluster headache, nicknamed "suicide headache", is a neurological disease that involves, as its most prominent feature, an immense degree of pain in the head. Cluster headaches occur periodically: spontaneous remissions interrupt active periods of pain. The cause of the disease is currently unknown...

 and to counteract the problems with sexual dysfunction

Sexual dysfunction

Sexual dysfunction or sexual malfunction refers to a difficulty experienced by an individual or a couple during any stage of a normal sexual activity, including desire, arousal or orgasm....

 experienced by some users of the selective serotonin reuptake inhibitor

Selective serotonin reuptake inhibitor

Selective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitor are a class of compounds typically used as antidepressants in the treatment of depression, anxiety disorders, and some personality disorders. The efficacy of SSRIs is disputed...

 (SSRI) antidepressant

Antidepressant

An antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...

s. Pramipexole has shown robust effects on pilot studies in a placebo-controlled proof of concept

Proof of concept

A proof of concept or a proof of principle is a realization of a certain method or idea to demonstrate its feasibility, or a demonstration in principle, whose purpose is to verify that some concept or theory that has the potential of being used...

 study in bipolar disorder

Bipolar disorder

Bipolar disorder or bipolar affective disorder, historically known as manic–depressive disorder, is a psychiatric diagnosis that describes a category of mood disorders defined by the presence of one or more episodes of abnormally elevated energy levels, cognition, and mood with or without one or...

. It is also being investigated for the treatment of clinical depression

Clinical depression

Major depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and by loss of interest or pleasure in normally enjoyable activities...

 and fibromyalgia

Fibromyalgia

Fibromyalgia is a medical disorder characterized by chronic widespread pain and allodynia, a heightened and painful response to pressure. It is an example of a diagnosis of exclusion...

.
Pramipexole acts as a partial

Partial agonist

Partial agonists bind and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist...

/full agonist at the following receptor

Receptor (biochemistry)

In biochemistry, a receptor is a molecule found on the surface of a cell, which receives specific chemical signals from neighbouring cells or the wider environment within an organism...

s:

• D_2S receptor (K_i = 3.9 nM; IA = 130%)
• D_2L receptor (K_i = 2.2 nM; IA = 70%)
• D₃ receptor (K_i = 0.5 nM; IA = 70%)
• D₄ receptor (K_i = 5.1 nM; IA = 42%)

Pramipexole also possesses low/insignificant affinity (500-10,000 nM) for the 5-HT_1A, 5-HT_1B, 5-HT_1D, and α₂-adrenergic receptor

Alpha-2 adrenergic receptor

The alpha-2 adrenergic receptor is a G protein-coupled receptor associated with the Gi heterotrimeric G-protein. It consists of three highly homologous subtypes, including α2A-, α2B-, and α2C-adrenergic. Some species other than humans express a fourth α2D-adrenergic receptor as well...

s.