As I've written in other posts, there's speculation that oxytocin could relieve persistent genital arousal disorder (PGAD), also known as persistent genital arousal syndrome, or PGAS.
A couple years ago, a doctor posted a letter saying he's had success treating PGAD with oxytocin. However, he hasn't responded to me via phone or email, nor has he published anything else about this.
Nevertheless, I think there's a strong possiblity that this treatment could help. Usually, there is a strong release of oxytocin from the pituitary gland at orgasm, followed later by a release of prolactin. Oxytocin, among other things, causes smooth muscle contractions, including contractions of the uterine walls during orgasm. These contractions could be responsible for releasing blood engorging the clitoris.
After orgasm, prolactin reduces sexual desire temporarily, increasing the relaxation caused by oxytocin.
If for some reason enough oxytocin isn't released at orgasm, engorgement and excitation of the nerves might not dissipate.
While many women report that doctors don't take this condition seriously, let alone have any help for them, women with PGAD might get relief from naturopaths or acupuncturists. Acupuncturists can stimulate the release of oxytocin by placing the needles at certain points. Because Chinese medicine has a different conceptual framework from Western medicine, you need to ask the acupuncturist to stimulate the points "forbidden during pregnancy." They're forbidden during pregnancy because they release oxytocin, which could produce premature labor.
Naturopaths also have access to oxytocin lozenges which are placed under the tongue. A naturopath may be more willing than an MD to consider trying this at your request. If you suffer from persistent genital arousal disorder, it's certainly worth a try.
You can read my previous post on oxytocin and PGAS or PGAD here: Oxytocin Could Relieve Persistent Genital Arousal Disorder.