Thank you for the details,
The bad taste may be due to two separate things--if you are not taking anything for acid reflux, this is a common cause of what you are experiencing. Try using over the counter omeprazole (as long as it does not interact with anything you are taking) for one week to see if this makes any difference.
The second issue is the postnasal drainage. This is also a very common cause of bad breath as well as a bad taste. If you do not have any history of high blood pressure, you can try using a decongestant like sudafed
. However, often the best treatment for drainage is a nasal steroid spray, which is only available by prescription.
Using a nasal saline spray (which is over the counter) may also be helpful for you.
Hopefully, these measures will clear it up for you!
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