Hello, thanks for using Health Care Magic.
After use of several anti itch drugs especially antihistamines, may be its time to consider another cause.
It is possible to be Trichomoniasis
caused by a small protozoan which causes intense itching. It is sexually transmissible but then easily treated with metronidazole
Another possible cause could be scabies
which is cause by a small parasite with intense itching as well but more in the night and affects generally more than one person.
What you should do is try metronidazole tablet ( both partners): 2 grammes single dose and with oral antihistamine, review the drug noticeof any drug you are currently taken or which you took prior to the itch; the drug has as side effects allergy
then stop it.
Best regards and hope this helps.