What otc allergy medications are safe to use while taking methadone daily for pain mgmt treatment? 140 mgs per day. thank you.

2nd generation: antihistamines are best, because they do not increase sedation, and don't have major interactions or effects on sedation. They are all pretty much OTC these days as well. The best, in my experience, is Loratadine (Claritin). Unless you have severe congestion, I would avoid the Claritin-D or pseudephedrine (Sudafed), since it likely will give a false positive amphetamine test on urinalysis.