Long standing thick vaginal discharge associated with itching is mostly a fungal infection . It would be helpful to consult and get examined by a gynaec Dr before you start any drug.
Next Steps
to relieve the itching for now you can use candid b ointment for local application.do not keep washing the area..
Health Tips
you will need treatment that would consist of vaginal tablets and oral tablets. so it's better to have a gynaec check up.