>>162747
NTA but assuming you mean a first generation antihistamine, you probably wouldn't die but it would definitely increase the risk of a bad trip, a seizure or something else. Antihistamines and DXM potentiate each other, and antihistamines generally give you bad trips. Once I was tripping on I think 300-400 mg of DXM and 100 mg of DPH and I saw a bunch of spider webs with little spiders on my ceiling, which would disappear or reappear whenever I closed and opened my eyes, but I was never sure if my eyes were opened or closed because I was either just looking at my ceiling without spiders or with spiders.

The 300/300 DXM/DPH combo is supposed to make the deliriant trip moar bearable but I found it felt just as bad as any DPH trip though the visuals were really cool.