Posted by Sad Panda on June 12, 2004, at 2:10:40
Hi Questionmark,
Recently I said:
> Cyproheptadine is a H1, 5-HT1 & 5-HT2A antagonist. 5-HT2A blockade relieves anorgasmia, 5-HT1 blockade temporarily stops the antidepressant effect SRI's & MAOI's give which hopefully will increase libido. If your libido is OK or not really a problem, then I would have a look for a 5-HT2A blocker that isn't a 5-HT1 blocker.
>
> Cheers,
> Panda.
>You asked:
>Thanks Panda. But are you sure that cyproheptadine is a 5-HT1 antagonist? i've never seen/read that before. But that is a very helpful and important piece of information to me if it's true, so thank you if it is (& for responding, regardless).
>
>I found this today at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=98359370
"Treatment of the serotonin syndrome with cyproheptadine.
Graudins A, Stearman A, Chan B.
Department of Emergency Medicine, Westmead Hospital, NSW, Australia.
The serotonin syndrome is the result of excess stimulation of central nervous 5-hydroxytryptamine (5HT)-1a and 5HT-2 receptors. The diagnosis requires a history of exposure to agents active at serotonin receptors and the presence of alterations in mental status, autonomic instability, and neuromuscular abnormalities such as tremor, hyperreflexia, or myoclonus. In this descriptive case series, five cases of serotonin syndrome are reported. All patients gave a history of recent exposure to one or more serotonergic medications, including moclobemide, paroxetine, sertraline, and venlafaxine, with clinical evidence of serotonin syndrome. All patients were administered cyproheptadine (4-8 mg orally) for serotonergic signs. Three had complete resolution of signs within 2 h of administration. Another two had a residual tremor or hyperreflexia following the first dose, which resolved following a repeat dose. There were no adverse outcomes from cyproheptadine use. The role of specific serotonin receptor antagonists such as cyproheptadine in the treatment of the serotonin syndrome remains to be delineated. Its use should be considered an adjunct to supportive care. Currently, it is unknown whether cyproheptadine modifies patient outcome."
This is why I said that Cyproheptadine blocks 5-HT1, becuase it appears to be the best serotonin syndrome treatment. The putative mechaism for SSRI's is generally believed to be agonism of 5-HT1 receptors, while Cyproheptadine probably blocks these because it causes depression. So when I said 5-HT1 & 5-HT2A, it's probably a 5-HT1A & 5-HT2 blocker and likely to be a nonselective 5-HT1 blocker.
Cheers,
Panda.
poster:Sad Panda
thread:355954
URL: http://www.dr-bob.org/babble/20040608/msgs/355954.html