The role of prolactin inhibition in sexuality

Known as the hormone of pregnant and breastfeeding women, prolactin, according to multiple studies you can find here and here, influences male sexuality more than until now considered.

In particular, according to the research that examined more than three thousand men between the ages of 40 and 70, low levels of prolactin are associated with lower than average sexual function, little pleasure and psychologically a tendency to depression.

The study measured testosterone levels in volunteers, until now considered the primary engine of sexuality in men, body mass index, cholesterol, sugars and prolactin. The men then filled in questionnaires on their lifestyle, diet, smoking and sexuality.

The results, the report published in The Journal Of Sexual Medicine explains, show that the presence of low prolactin is accompanied by a series of symptoms of low sexual and mental health: men who had lower than average prolactin, albeit in levels still considered normal they have all reported a deterioration in their sex life, in addition to depression.

Consequence of hyperprolactinemia in men:

  • In men, hyperprolactinaemia resulting from a prolactinoma can determine:
  • Erectile dysfunction;
  • Reduction of hair on the face and in general on the whole body;
  • Gynecomastia, or abnormal development of the breasts;
  • Male galactorrhea (very rare).

Dostinex in ED and lack of sexual desire caused by hyperprolactinemia

To understand the pharmacological therapy of prolactinoma, it is necessary to take a small step back and inform the reader that dopamine – the known neurotransmitter associated with Parkinson’s disease and addiction to many drugs – plays the important role of physiological inhibitor of the secretion of prolactin; in other words, in a healthy person, to stop the production of prolactin (to avoid an excess of it in the blood) dopamine is secreted.

Returning therefore to the pharmacological therapy of prolactinoma, this treatment consists substantially in the administration of dopaminergic agonists like Dostinex, that is to say medicines that mimic, once assumed, the effects of dopamine against the secretion of prolactin by the pituitary gland.

It should be pointed out that among the dopaminergic agonists used in the treatment of prolactinoma, bromocriptine and cabergoline stand out, due to their additional ability to reduce the size of the tumor mass. In other words, bromocriptine and cabergoline perform not only the same inhibitory action as dopamine (against pituitary cells that produce prolactin), but are also able to regulate prolactinoma.

Acting mainly on symptoms, prolactinoma drug therapy is a treatment that patients must undergo for a long time, if not for the rest of their lives.

Statistics show that the use of cabergoline in people with ED and lack of sexual drive caused by prolactinoma restores erectile ability and libido in up to 80% of clinical cases.

Thus, bromocriptine and cabergoline are excellent drugs for the treatment of prolactinoma, so much so as to constitute the first line treatment for this type of tumor.

Dopamine agonists and exaggerated sexual behavior

Inhibition of prolactin, the principal action of Dostinex, is associated with expressed dopaminergic effects. From an analysis of spontaneous reports and literature, the Committee that deals with the assessment of adverse reactions in the European Union (EU Pharmacovigilance Working Party, PhVWP) highlighted that the pathological gambling syndrome, the increase in libido and hypersexuality are a class effect associated with the indicated dopamine agonists: for the treatment of Parkinson’s syndrome, restless leg syndrome and endocrine disorders (you can find the full report here).

In some patients treated with dopamine agonist drugs, a chronic and progressive difficulty was observed to resist the impulse to gamble, with negative consequences on their personal, family and work relationships. Furthermore, some patients treated with the always dopamine agonist drugs (the class of drugs Dostinex falls into) showed abnormal sexual behavior that resulted in negative consequences for themselves and others. Such undesirable behaviors have occurred especially at high doses and generally have been shown to be reversible with treatment reduction or interruption.

On the basis of the new evidence, the PhVWP recommended to modify the prints of the medicinal specialties of Dostinex. Therefore, doctors must warn patients and their families about the possibility of unusual behaviors occurring.

Cases of pathological gambling syndrome, increased libido and hypersexuality have been reported in patients treated with dopamine agonists. Patients treated with dopamine agonists, for Parkinson’s syndrome, especially at high doses, have been reported cases of pathological gambling syndrome, increased libido and hypersexuality, generally reversible with treatment reduction or interruption.