Hypersexuality and Neurological Disease

      The word nymphomania is often used in an almost slang sense in modern language, especially in the abbreviated form of “nympho”.  While it is often used loosely, it is important to remember that there is a clinical basis for the word, although the disorder is more commonly called hypersexuality, perhaps to move away from the connotations that are now attached to the word nymphomaniac.  Upon researching hypersexuality, many articles came up that related various drug therapies in relation to hypersexuality, the most common one was any drug therapy related to Parkinson’s disease.  There were also articles about hypersexuality and drug therapy for strokes and epilepsy.  I found this to be quite interesting due to the fact that one does not often associate hypersexuality with older people, who are much more likely to have developed Parkinson’s disease or have had a stroke.  To discover how the two were related, research had to be done to discover what the effects of these diseases and their drug therapies had on the brain.

      Parkinson’s disease is a disease that affects the central nervous system and impairs the patient’s motor skills as well as speech.  The disease is thought to be caused by a decrease in stimulation of the motor cortex by the basal ganglia, which is caused by insufficient amounts of dopamine.  Parkinson’s is chronic and progressive and there is currently no cure, but drugs are used to relieve symptoms and slow the progression (1).  The drugs that are used are L-dopa drugs, dopamine agonists, and MAO-B inhibitors.  All of these drugs have an effect on dopamine in the brain, whether it is a transformation of the drug directly into dopamine, stimulation of dopamine receptors, or the prevention of the breakdown of dopamine (1).

      There are several documented cases of Parkinson’s disease patients experiencing hypersexuality due to their drug therapies for their disease symptoms.  A study at the Mayo Clinic showed that thirteen Parkinson’s patients experienced hypersexuality.  This study attributed the problem to an inhibition of prolactin secretion (2).  Prolactin is a hormone that plays a part in regulating the levels of sex hormones, and it also represses the effect of dopamine.  It can also be indicative of the level of sexual satisfaction a person is feeling; high levels of prolactin are usually associated with impotence and a loss of libido as well as a decrease in sex hormone (3).  So if a patient was on drugs that inhibited the release of prolactin, the low levels might have the opposite effect and increase a person’s libido.  Another study looked at a patient who was taking L-dopa and a dopamine agonist called bromocriptine (4).  This patient’s dosage of these drugs might have been too much, causing too large of an increase in dopamine, causing their hypersexuality.  In a third example of a Parkinson’s patient and hypersexuality, a man with Parkinson’s developed delusional jealousy and frotteurism, which is a disorder where the person rubs against or touches another person in order to achieve sexual arousal or orgasm (5).  This patient was on pergolide, which is another dopamine agonist that stimulates dopamine receptors (1). Upon decreasing the dose of pergolide in combination with taking quetiapine, an atypical neuroleptic drug that is responsible for antagonist activity on dopamine and serotonin receptors, which allows normal levels of dopamine to be released, the patient’s behavior returned to a normal level (5).

      There were two different articles that mentioned strokes in relation to hypersexuality.  In one case, a man developed a psychotic disorder with delusions due to a stroke, and also developed hypersexuality and delusional jealousy.  The man was given quetiapine, like the patient with Parkinson’s previously discussed above.  After only two days on the dose of quetiapine, the man showed a significant difference in his hypersexual behavior (6).  In another case of strokes in relation to hypersexuality, stroke patients with lesions on their temporal lobes due to the stroke developed hypersexual behavior, but it was not said if they were given medication to remedy the situation.  The article also mentioned that animals that had temporal seizures also demonstrated hypersexuality (7).

      The epilepsy patients discussed had temporal lobe epilepsy, so they also had damage to their temporal lobes like the stroke patients.  In the cases of the epilepsy patients, both patients were taking the drug Lamotrigine, or LTG.  LTG is an anticonvulsant that reduces epileptic seizures by decreasing the levels of glutamate (8).  Glutamate is the most abundant fast excitatory neurotransmitter and is implicated in epileptic seizures because in experiments, the injection of glutamate into neurons causes depolarizations, which can cause voltage activated calcium channels to open, causing the release of more glutamate and more depolarizations.  These depolarizations look very similar to paroxysmal depolarizing shifts in epileptic attacks (9).  In the cases of the epilepsy patients, the LTG had the same effect on both but to a different degree.  In the first patient, the LTG caused intense sexual desires that were uncomfortable and unpleasant for the patient.  The patient’s dosage was decreased until his level of sexual desires returned to the levels previous to taking LTG.  In the second patient, the LTG also increased his sex drive, but not to the point of discomfort, instead the patient enjoyed this newfound revival of his sex life (8).  Another article mentioned that several temporal lobe epilepsy patients experienced hypersexuality after having a temporal lobe resection operation (10).

      After looking at all of these examples of patient’s with hypersexuality due to other medical causes, it seems that the levels of dopamine play the most important role for many.  This makes sense as dopamine is associated with the pleasure system of the brain, and dopamine is released during sexual activity.  As for the patients with damage to the temporal lobe, mesolimbic dopamine is associated with creativity in the frontal and temporal lobes, but it is unclear how this is related to hypersexuality exactly (11).  This is a good example of how much of our behavior is out of our actual control.  This is especially evident in the epilepsy patient who was extremely uncomfortable with his new sex drive and sexual desires, but could not change the way he was behaving due to the chemical imbalance in his brain.  I feel this is also a lesson in taking care what drugs should be given and how much in order to produce the optimal effect without inducing other unwanted problems for a patient.

WWW Sources

1) http://en.wikipedia.org/wiki/Parkinsons_disease, definition page, Wikipedia

2)http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2575449&dopt=Citation, article abstract, PubMed

3) http://en.wikipedia.org/wiki/Prolactin, definition page, Wikipedia

4)http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6685318&dopt=Citation, article abstract, PubMed

5) Cannas,-Antonino; Solla,-Paolo; Floris,-Gianluca; Tacconi,-Paolo; Loi,-Daniela; Marcia,-Emanuele; Marrosu,-Maria-Giovanna. “Hypersexual behaviour, frotteurism and delusional jealousy in a young parkinsonian patient during dopaminergic therapy with pergolide: A rare case of iatrogenic paraphilia.” Progress-in-Neuro-Psychopharmacology-and-Biological-Psychiatry. Vol 30(8) Dec 2006, 1539-1541., article, through Psycinfo

6) Chae,-Beang-Jin; Kang,-Byung-Jo. “Quetiapine for hypersexuality and delusional jealousy after stroke.” Journal-of-Clinical-Psychopharmacology. Vol 26(3) Jun 2006, 331-332., article, through Psycinfo

7)http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3718200&dopt=Citation, article abstract, PubMed

8)http://sfx.exlibrisgroup.com:9003/brynm?sid=SP:PSYI&id=pmid:&id=doi%3a10.1016%2fj.yebeh.2006.01.005&issn=1525-5050&isbn=&volume=8&issue=3&spage=663 &pages=663-665&date=2006&title=Epilepsy%20and%20Behavior&atitle= Hypersexuality%20in%20two%20patients%20with%20epilepsy%20treated%20with%20lamotrigine.&aulast=Grabowska-Grzyb&pid=%3Cauthor%3EGrabowska%20 Grzyb%2c%20Albena%3bNaganska%2c%20Ewa%3bWolanczyk%2c%20Tomasz%3C%2Fauthor%3E%3CAN%3E2006-05826-033%3C%2FAN%3E%3CDT%3E Journal%3bPeer%20Reviewed%20Journal%3bOriginal%20Journal%20Article%3C%2FDT%3E, article, through Psycinfo

9) http://en.wikipedia.org/wiki/Glutamate, definition page, Wikipedia

10)http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=abstractplus&db=pubmed&cmd=Retrieve&dopt=abstractplus&list_uids=12609419, article abstract, PubMed

11) http://en.wikipedia.org/wiki/Dopamine, definition page, Wikipedia