What is the best home remedies for post nasal drip that also causes halitosis had it for many years?

Have an evaluation: With an ENT initially to determine the cause and opt for corrective treatment options rather than palliative treatment. In the interim maintain excellent oral hygiene and make brushing your tongue part of your hygiene regimen. There is an oral rinse called smart mouth (over the counter) that can help with the halitosis in the meanwhile. Hope this helps.

May be normal: In dental school, an oral surgeon once told us there is no such thing as 'post nasal drip' as an anomaly--we all have it. It is normal, and most of us drain a quart of fluid a day down the back of our throat. People that say they have a problem have just become more aware of that draining. That being said, there are some that get relief using otc allergy medicines. Best of luck.